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bitingmidge
23rd October 2005, 12:37 PM
I know that strictly speaking this is an "announcement" or even a "website" but I thought the GIS is a design after all, and here's as good a place as any to provide a link to my heavily updated Goat Island Skiff Web Pages (http://homepage.mac.com/peterhyndman/GISintro.htm).

Note in 2011 - Goat Island Skiff is on facebook (http://www.facebook.com/home.php?sk=group_215207561847940&ap=1)

The old site started as one page with a 250kb photo in 1998, were updated somewhat in '99 with a heap of small photos, and some basic headers, but it seemed like it was time for me to come to terms with rollovers, and CSS and stuff.

Since the pages are very much a learning curve for me, I'd appreciate feedback on how (if) they work, particularly with older browsers. Dial up users may need a bit of patience on the Diary and Links pages until all the images are loaded.

Oh, and any discussion on the boat would work in this thread too!

More Goat Island Skiff pics (http://www.flickr.com/photos/boatmik/collections/72157600859659666/)
More Goat island Skiff videos (http://www.youtube.com/profile?user=boatmik#grid/favorites)

Cheers,

P

YouTube - 100_0033.MOV

Wild Dingo
23rd October 2005, 04:22 PM
Nice site midge... :cool:

one thing... the pics come up okay in all areas (Im on a very fast dialup) but the set up doesnt give you a nice long CLOSE look at them... also "could" the pics be clickable so you can see a larger pic for clarity etc??... Im sorta of the type that likes to spend hours checking out the processes that people go through... a slow look ie: the lofting process boards and plans side by side then pencil and batten drawing the lines next jogsaw and cutting the sections... then checking theyre all right setting them on the moulds... etc etc etc but others dont like that theyd rather take a quick peek and be done... no worries each to their own eh ;)

Just ideas and thoughts... otherwise looks like a great wee boat with the potential for a heck of a lot of fun hootin around!! :cool:

bitingmidge
25th October 2005, 04:04 PM
Shane,

Thanks, yep, she's a lot of fun!

I tried the click thing first, but didn't like it.... if you leave the mouse sitting over the pic, it should stay there as long as you like.

On the other hand, I know what you mean about bigger pics, and will do that eventually (with a click and a new screen), it's just that the pics I've got are not that good; I'm pushing the limits of their resolution now!

Thanks for the feedback, I'll work on the Dingo Changes in a month or two, once I've got the rest of the site done!


Cheers,

P

bitingmidge
29th January 2007, 12:18 PM
For those interested, I've posted a few nice shots of "Gruff" with Michael Storer at the helm on my Flickr gallery (http://flickr.com/photos/bitingmidge/sets/72157594503716554/).

I'm hoping to get to and re-hash the original web site mid-year, but don't worry, you'll be the first to know! Here are a couple of shots to get you going, there are a few more there now, and a heap coming tonight!

http://farm1.static.flickr.com/157/371533428_9f9a0d198e.jpg


http://farm1.static.flickr.com/151/371533253_549617c05b.jpg

You've gotta feel sorry for Mik, I get him working painting my boats, and between coats have him out sailing my other boats so I can get decent photographs!

Cheers,

P
:D :D :D

Wood Butcher
29th January 2007, 02:16 PM
and between coats have him out sailing my other boats so I can get decent photographs!

Yeah, like he's complaining!:p:rolleyes:

Wild Dingo
30th January 2007, 02:10 AM
And would I?? Not a bloody chance!! hell id be there with bells on if I could get there! :doh:
Great day mate!! Well done to all :2tsup:

dennyinsequim
16th April 2007, 02:03 AM
Hi, I have a few newbie sort of questions, going for a sail in an open boat in the sea of cortez has been on the list for a long time ( I've done a little nosing around there in kayaks and power boats) I've had my eye on the core sound series for a long time but I'm more of a user than a builder. I recently found this forum and the GIF and it really looks like a boat I could manage to build and I like the look. I'd be solo and the light weight would be a real bonus for getting her up the beach as well as being able to put it on top for the long drive eliminating trailer breakage issues. Thanks for any help, it's too late to keep this short but like all newbies I have a lot of questions and used the search feature pretty hard yesterday. denny

dennyinsequim
16th April 2007, 02:58 AM
Having a look at my post I realize a never ask a question, I'm just looking for opinions on the suitability of the GIS for a trip like this. The wind in baja can come up pretty quickly and it's pretty remote. I understand that's not an easy one to answer because the drivers judgement is the main thing.
Honestly I suspect I'm going to order the plans and try to build one either way as the look and performance really appeal to me and I have a lot of water to sail on right here at home. denny

the link is to a couples page describing their trip and the conditions.

http://www.smallboatforum.com/PDFfiles/BeachCruisingBaja.pdf

bitingmidge
16th April 2007, 08:28 AM
Denny,

After reading the article, I'd say the GIS is at least the equal of "Loon" in every respect, and of course a little lighter.

The authors were well aware of the risks of a voyage like that, and I'd be very, very wary of takling it alone. Travelling alone throws up a host of new challenges, and certainly increases the degree of difficulty of the voyage.

While the GIS has full flotation as well, that wouldn't be a lot of use to you if you were injured and unable to get back into the boat!

You may also find that you'll need some special equipment if you are going to manage to cartop alone as well.

I think in summary, the boat is capable of carrying a well prepared and experienced crew on a journey like that, but a well prepared and experienced crew may choose to do it differently!

All the best, I'd love to see the pictures of your voyage, but come to think of it, there's another disadvantage of travelling alone, no one to take the pics!

Cheers,

P

dennyinsequim
16th April 2007, 10:28 AM
Thanks for the response, I've enjoyed your website and of course your beautiful GIS, 95% of my use would be around here and would be trailered, it's just the baja roads are notorious. I'll spend a season or two cruising here before I head south so I'll have things pretty well sorted out. I'm also going a bit earlier than they did so the wind is more predictable and the fishing is prime.
I mostly wondered about how easily a balanced lug can be reefed and hopefully I can order my sail with an extra reef point.
I'm going to get some plans ordered up and try a build, I suspect I'll be back with more questions. thanks again denny

bitingmidge
16th April 2007, 11:03 AM
I've alerted Michael Storer to your posts and he should be here shortly! :wink:

The Lug can be easily reefed, but it's a small boat and I wouldn't want to be doing it underway "when it was needed". You can easily beach the boat and do what you need or drop the sail while underway, but reefing in an sailing dinghy, no matter what the theory says is best left to dry land!

Looking forward to more posts from you!

cheers,

P

Boatmik
16th April 2007, 01:17 PM
Howdy,

Thanks for the alert Midge.

It is always a problem for a designer as to what to say in these sorts of circumstances.

Like the GIS is a good boat that sails well and with my amount of sailing experience I would be happy sailing down the coast on good weather reports and after making good preparations.

BUT - and it is a big one - I really can't say whether it is safe for anyone else to do so.

If the weather was as in the article's pictures above ANYONE could do it - but I can certainly imagine that if I was doing the trip and the weather turned nasty then I could be in serious danger in some circumstances.

The downside of the GIS is exactly as the boat shown doing the BAJA cruise in the pictures - if capsized it takes a LOT of water and takes some time and effort to bail out and while I've done it several times with little trouble I don't think i would like to do it 5 times in a row! Probably I would recommend a second person be along for just those sorts of eventualities - one balances the boat the other bails.

With the BAJA boat in the cruise pictures - what happens to their outboard if they capsize - if it gets drowned in a capsize ... then what? How much does their idea of safety depend on the outboard?

You see the point is that if everything goes OK - then you can do any sort of trip in just about any boat - even a PDRacer - but if things go wrong you are very much on your own on that sort of coast.

If most of your sailing will be in other more populated places then that is enough reason in itself to build a GIS. Then as you get to know the boat and what it can do - and more important - get to know your abilities/limitations then you can extend what you are doing.

One modification i would consider is to enlarge the buoyancy tanks (or box in the middle seat) so that the boat floats higher when full of water and there is less to bail.

As far as lightness goes - the GIS is light - unladen I can drag her up Midge's beach and onto the grass - but once some cruising gear is aboard you will need an inflatable roller or two to move the boat by yourself.

One additional thing ... I am working on an extended version of the GIS which has a self draining cockpit as a RAID boat. It answers the main criticism I make above which is that if capsized it will come up with no water aboard and it will still be a lot lighter than the boat in the article above. I've attached a pic - the floor drains out through the back of the boat and the boat will come upright empty of water - so no bailing and a considerable increase in safety margin. There is also some chance of carrying some water ballast under the false floor in the midsection of the boat.

Best wishes
Michael Storer

Boatmik
16th April 2007, 01:48 PM
By the way - I have put together a pictorial article that shows much of the stuff I have learned about setting up lug rigs over the last couple of decades.

http://www.storerboatplans.com/GIS/downhaul.jpg

Not only will it help with setting up a GIS but it will also help set up any lug rig - but particularly the balance lug which is has the best all-round performance of the variants.

There is a link to the new page here
http://www.storerboatplans.com/GIS/GISplan.html

Best wishes
Michael.

dennyinsequim
17th April 2007, 01:51 AM
Thanks Michael, Your and Peter's websites are great and I don't know how I managed to take so long to find them. I'm going to get going and build a GIS and hope to enjoy the process enough to follow up later with the raid version as I suspect it's probably going to be just what I need for the trip.
I re-read both sites last night, really well put down information and a lot of the mystery's I had about the whole boat building process are clearly explained.
I'm lucky to live close to a great source for plywood and lumber (Edensaw) in Port Townsend.
As I mentioned above the trip south is a few seasons away and when I go there will be no time constraints, meaning if it's not right I'm on the beach. thanks again denny

Ziff
16th May 2007, 08:51 PM
Hi everyone
Newbie here, just found this forum a few days ago and been reading a lot of it. I have just finished building the GIS two weeks ago which was a 10 month project, this is my first ever post so I hope these pics turn out. Im sorry I dont have any pics of the maiden voyage, in all the excitement someone forgot to take the camera what a dope.
My biggest problem at the moment is what to name it?
If I knew about this forum I probably would have taken more pics of the build however only have a few.
The maiden sail was fantastic, this skiff was far better than I had ever imagined and the lightest boat I have ever sailed, just glides through the water with very little effort.
I will post some more pics of the next sail if I can remember the camera.

Regards
Stephen

bitingmidge
16th May 2007, 11:54 PM
The maiden sail was fantastic, this skiff was far better than I had ever imagined and the lightest boat I have ever sailed, just glides through the water with very little effort.
Stephen,
Welcome to the forum and to "the club"!

It's really great to have someone else who understands my raving about the thing!

Cheers,

P
:D

Boatmik
17th May 2007, 02:32 PM
Hi everyone
Newbie here, just found this forum a few days ago and been reading a lot of it. I have just finished building the GIS two weeks ago which was a 10 month project, this is my first ever post so I hope these pics turn out. Im sorry I dont have any pics of the maiden voyage, in all the excitement someone forgot to take the camera what a dope.
My biggest problem at the moment is what to name it?
If I knew about this forum I probably would have taken more pics of the build however only have a few.
The maiden sail was fantastic, this skiff was far better than I had ever imagined and the lightest boat I have ever sailed, just glides through the water with very little effort.
I will post some more pics of the next sail if I can remember the camera.

Regards
Stephen

Howdy Stephen,

Great looking boat!!! Thanks for putting the pictures up.

The only thing that I can see is with the sail. It needs to go a little further up the mast - maybe 150mm and move the boom slightly forward - maybe only a couple of inches.

Make sure the block (pulley) on the yard is about halfway.

Great to have another boat on the water. Is it OK to use your photos and words on my website?

Michael

Ziff
17th May 2007, 06:37 PM
Can anyone tell me if it makes any difference if you have the batton in place or not while reefing?

bitingmidge
17th May 2007, 06:40 PM
I've never actually used a batten so the answer is a resounding no! :D

I should also say I haven't reefed either. The boat is relatively comfortable (with enough crew weight) in the high teens of knots, after that we're usually doing other stuff anyway.

We do have some pics of Mik in ours in probably 15knots (Mik to correct if he thinks I'm wrong) and he could hold it by himself, although that's close to the limit of comfort for a single hander. Two up, not a problem although I am referring to off the beach sailing, and reefing would have advantages if one was cruising home over a long stretch of water.

cheers,

P

Ziff
17th May 2007, 07:02 PM
Thanks for the welcome and the setup advice I will try this out when I go out again probably on the 26 or 27th May, cant wait to go out again.
Don't know if you noticed that the mast is the new square hollow type. The only thing about a square mast is that you have to tie the pulldown to the mast or it jams and does not move freely, you can see in one of the pics how I have done so.
I am probably doing things back the front and did the harder project first but I was so impressed with the GIS that I purchased the Eurka plans last week and picked up the ply today so watch out for the build on the other thread site coming soon, will take pics this time.

Boatmik
18th May 2007, 12:45 AM
Howdy Ziff,

The battens have one really good use. If cruising they reduce the power the sail puts out by a fair degree. I found this out with my BETH sailing canoe which has the same setup.

I originally lifted the batten idea from sailing canoes from the 1870s.

If you want to go racing or just get more power pull the battens out.

I think both options work quite well.

Michael

Boatmik
18th May 2007, 12:54 AM
The only thing about a square mast is that you have to tie the pulldown to the mast or it jams and does not move freely, you can see in one of the pics how I have done so.

I am probably doing things back the front and did the harder project first but I was so impressed with the GIS that I purchased the Eurka plans last week and picked up the ply today so watch out for the build on the other thread site coming soon, will take pics this time.

Most of the time the red lashing that you have used to hold the boom reasonably close to the mast needs to be quite loose to enable the boom to swing out on both sides. It even jams if overtightened on the round mast.

If you get the chance to get some pics of the downhaul jamming that might be interesting to see - I can't visualise what you have done or why.

I'm glad it has solved the problem though!

Michael

Ziff
18th May 2007, 07:29 AM
I will clarify the Jam, It is the red lashing that is jamming not the pulldown and although in the photo the red lashing looks tight, it is not it has enough slack to move quite freely, what I found is that the boom is trying to move forward all the time and causing the jam, so when I tied the pulldown to the mast this holds everything from pulling forward and jamming does not happen anymore. I suspect the same movement could be happening to the other rigs and it may be worth a try even on the round mast.

I have not used the batten's as yet, conditions were very light in the maiden sail. I did not know they reduce power.

How do you insert other peoples quotes into the threads?

Youre up quite late, don't you ever sleep?

Regards
Stephen

Boatmik
18th May 2007, 11:07 AM
Ha!

Well designing boats is only part of it. To have a reasonable web presence I have to keep writing stuff and creating links on the web - so I do that from time to time. For example I put a link from my GIS pages on the website to this thread and I am about to do a link from my blog to the thread as well.

(another late night, eh!?)

Thanks for explaining the jamming - I understand now - and it is a neat solution. I will get round to putting it up in my rigging guide unless I can think of something even better - but I like the simplicity.

MIK

bitingmidge
18th May 2007, 11:17 AM
How do you insert other peoples quotes into the threads?
Stephen,

If you look to the right hand side of the bottom of the post you'll see a button marked "quote". Hitting that will bring up a reply window with the quote already formatted, or you can use the tool bar above the reply box, where you'll see a little icon that looks like a cartoon bubble.

Or you can type "QUOTE" in square brackets [] before, and /QUOTE in square brackets [] after your quote.
I can't type it as it would dissapear, like it did for this text!


Cheers,

P

arbordg
24th May 2007, 06:11 AM
Ziff - Looks like you did a fine job. Thanks for sharing the fotos

arbordg
24th May 2007, 06:41 AM
Denny - If you'd like to see a completed version up-close, contact me. I have one here in Portland. It's very quick & dirty, but still turned out very pretty (he said, ever so modestly) Truthfully, that speaks more to the quality of the designer than of the builders. I built "Sisu" with my two teenaged sons and an old friend (who's an accountant with rudimentary woodworking skills). One of the reasons we chose this boat to build was because it looked to be a relatively easy build. That way, the boys and friend Jerry could do a good bit of the work without Pa (I'm a professional woodworker) fussing about the quality of their craftsmanship. There are a few fotos at Mik's site of Sisu - underway, powered by a small outboard. Now we have the sailing rig done. We'd be happy to show her off.

dennyinsequim
26th May 2007, 02:57 AM
Hi Dave, Thank you for the offer, if I ever see a trip south coming up I'll see if we can make it work, I've seen your boats pictures and it looks great, it also looks like your really getting some good use out of it. I was given a 14 ft Sharpie with a sprit rig and have been out in it a fair bit lately, I hadn't really sailed a light boat much before and it's pretty well confirmed the GIS should be just right for what I'm wanting to use it for. Denny

Ziff
7th June 2007, 04:38 PM
Hi
Finaly located the build photos I have, took me a while to figure out how to resize them for posting.
These photos show a few different angles of when I was setting the mast in position to glue the partner in position, not sure if you can see in last photo the piece of timber holding mast to top of brick fence. As can be seen there are no gunwhales ,inwhales or seats yet, even though the middle seat is there but not glued ,just sitting there. I have a few more pics will post them soon.

Regards
Stephen

Boatmik
8th June 2007, 12:48 AM
Howdy Ziff,

Nice pics indeed!!!

I don't have any of that stage - so thanks

MIK

thedumbox
25th June 2007, 12:36 PM
MIK, I'm very interested in your boat. Having built and owned a Bolger Featherwind (a skiff made from 1/4 ply), I hated the oilcanning of the bottom because it was not stiff enough. I've heard no complaints about the GIS in this regard, is this a concern? Also, the boat looks to be pretty high sided, sort of unconventional for a skiff. How deep is the GIS? Finally, I'm a fan of the sprits'l and was wondering how easy it would be to fit that particular type of rig on the boat. Thanks, TDO.

bitingmidge
25th June 2007, 01:14 PM
Gidday TDO and welcome,

No oilcanning at all. That's because the structure is cunningly designed to keep the span of the ply down to a minimum.

The boat may appear high-sided, but it's a nice utility skiff, and the gunwhales are a comfortable height for sitting on while sailing, and that's a great spot to perch, giving the helmsman a perfect view of his surroundings and the sail. It also means that the angle of heel can be pretty large before she ships any water over the leeward side. In fact it just never happens, not even with the leeward gunwhale on the water! :wink:

I'll let MIK answer the sprit question, it doesn't seem like a big deal to me, but the sail would need to be designed with it's centre of effort in the same spot as the other alternatives.

cheers,

P
:D

thedumbox
25th June 2007, 08:46 PM
Thanks, Midge. I hope I didn't come off as criticizing the design with regard to the "high sides". The waters where I sail don't get too warm and the what I perceive from pics as higher sides on the skiff is a benefit, although I can't say that perching on the gunn'l looks too comfortable.

Regards,
TDO

bitingmidge
25th June 2007, 09:05 PM
Thanks, Midge. I hope I didn't come off as criticizing the design with regard to the "high sides". The waters where I sail don't get too warm and the what I perceive from pics as higher sides on the skiff is a benefit, although I can't say that perching on the gunn'l looks too comfortable.
Not at all!

And once you try perching on the gunwhale, you'll wonder why you haven't been doing it for ever!

P
:wink:

Boatmik
26th June 2007, 12:57 AM
Howdy dumbox,

(I feel quite guilty calling you that!!!)

I like sprit rigs too but the advantage of the balance lug is that it allows the 105 square feet of the balance lug to be carried quite low down - so not as much heeling moment as otherwise. You would have to reduce the sail area with a sprit and lose some of the light wind performance that the lug is capable of.

Also as far as strong wind goes the lug reefs really easily with no extra gear required.

Like I said to Midge many years ago now ... if you like sailing fast try the balance lug rig rather than worry about all those battens and high tech spars and sails. In fact I've said that to everyone who had doubts about he lug rig - and they have all been more than happy with the way the rig works in its modernised traditional form. Did you see the pages on my website (accessible from the GIS page) about setting up lug rigs - I've learned a lot about making them perform really well.

The high sidedness of the GIS is quite cunning (if I say so myself). As per normal it gives a much greater reserve stability - the boat goes over a long way before the water starts coming in - but at the same time I fluked it a bit and produced a boat that doesn't look at all high sided - very sleek looking from almost every angle.

The high sidedness almost conspires to make the boat look a lot narrower than it actually is.

Hope this helps

Michael

thedumbox
26th June 2007, 02:34 AM
Hi, Michael, Thanks for the reply. I have been sailing with an 86sqft spritsail (quadrilateral, not the leg-o-mutton sharp rig shown on one of your PD racer's pics) on my current boat and just love it. I recently added a 21 sq ft jib to it (unstayed) which has made it zippier all around and surprisingly closer winded than I expected. Winds over 15knots require that I stow the jib since the mast bend pretty well spoils the set of the jib. Anyway, in contemplating a new build and not having a lot of money, I was considering the possibilities of using my current rig on the GIS.

A couple of things, keeping in mind that I have read your sight on sailing the GIS several times. First, I sail regularly in 2 foot chop on large inland lakes (this is not motorboat slop) and was wondering if you think the GIS would handle such conditions well. I've not seen much written on its rough water capabilities.

Secondly, I see that you are contemplating a longer GIS -- a raid boat? Have you thought about a less specialized, but longer daysailer type to compete with Reuel Parker's Small Ohio Sharpie (19.5ft x 5.5')?

Lastly, sorry to bug you with the questions. You are the first person I've found who appears to sail flat bottomed craft regularly and can give me some insight into the nature of their handling in a variety of conditions. My first boat was a Bolger Featherwind and I've been bitten by the skiff bug since. I did not think highly of that design and I have been searching since for a skiff that would do the type justice.

Thanks,
Dennis

Boatmik
28th June 2007, 09:12 PM
Hi, Michael, Thanks for the reply. I have been sailing with an 86sqft spritsail (quadrilateral, not the leg-o-mutton sharp rig shown on one of your PD racer's pics) on my current boat and just love it. I recently added a 21 sq ft jib to it (unstayed) which has made it zippier all around and surprisingly closer winded than I expected. Winds over 15knots require that I stow the jib since the mast bend pretty well spoils the set of the jib. Anyway, in contemplating a new build and not having a lot of money, I was considering the possibilities of using my current rig on the GIS.

Yep - that form of the sprit makes more sense - but if it doesn't have a boom you lose a lot of the performance. I keep meaning to do an article to show why boomless rigs are so poor in terms of performance - it is pretty easy to explain. But a sprit rig with a boom would work OK but you would have to make sure it balances over the same centre as the original.

I would also be concerned that the bigger, more powerful (more stable) GIS may break your existing mast.


A couple of things, keeping in mind that I have read your sight on sailing the GIS several times. First, I sail regularly in 2 foot chop on large inland lakes (this is not motorboat slop) and was wondering if you think the GIS would handle such conditions well. I've not seen much written on its rough water capabilities. If other light sailing boats are managing it OK it will manage it too. For all boats of this type it might depend a bit on the skill of the operator :-)


Secondly, I see that you are contemplating a longer GIS -- a raid boat? Have you thought about a less specialized, but longer daysailer type to compete with Reuel Parker's Small Ohio Sharpie (19.5ft x 5.5')?I'm looking at it but it has a long way to go before it is a full fledged set of plans. It will be very different from Reuel's boat. Most of the US Raid boats of that size come in around 700 to 900lbs for the hull. The extended GIS would come in around 250 and is designed for people who can really sail well. It would also be optimised for rowing.


Lastly, sorry to bug you with the questions. You are the first person I've found who appears to sail flat bottomed craft regularly and can give me some insight into the nature of their handling in a variety of conditions. My first boat was a Bolger Featherwind and I've been bitten by the skiff bug since. I did not think highly of that design and I have been searching since for a skiff that would do the type justice.

Here is some info from my GIS and BETH plans. The sailing of the hull is only part of it - the rig has to be right too - if you see the lug rig pages on my GIS pages there is a lot of information about getting that side right. It makes a HUGE difference.

MIK

Sailing the skiff

The skiff will sail much the same as most boats its size, but there are a few peculiarities that come with the flat bottom.


As with almost all boats the skiff will sail fastest if sailed level - with little or no heel – the exception is in very light winds when you are struggling to get up any speed at all the boat can be heeled over to 20° This reduces the wetted surface by around 25%. As soon as the boat has achieved any sort of consistent speed it should be brought upright.


When the water is very choppy the boat may slam badly if sailed upright. A small amount of heel will smooth its movement considerably. The minimum amount of heel that stops the worst of the slamming should be adopted.


The forward and aft buoyancy tanks are designed for use as seats when rowing. The boat will perform best sailing with crew weight concentrated around the middle thwart.


The final difference with many other boats is because there is no jib. This means that the mainsail boom should not be pulled in tighter than 10 degrees from the centreline of the boat.
Rowing the Skiff

If rowlocks are to be fitted they need to go 300mm behind the back edge of the centre seat. The oars need to be 9ft long.


Shorter oars can be OK if you only want to go short distances with low efficiency, but if covering real distance and planning to go out in stronger winds then the longer oars are highly recommended.


I have drawn up a set of classic oars for free download that will suit the GIS but with laminated plywood blades to make the blades highly robust.

21st September 2007, 03:33 PM
I am looking at a suitable boat to build for myself and my two young boys, 8 & 10, to learn to sail in, go camping, etc. Just the things the GIS seems so suitable for!

I have been looking at the Jordan Wood Boats, "Footloose". I even went so far as to order plans. But, the finished weight of 300 lbs puts me off when I compare it to the GIS ~130 lbs. As I look at the plans I also think it is more difficult to build than the GIS and would require more woodworking skill than I possess.

I have to say that the sprit sail used on the Footloose interests me due to the lack of a boom. With my complete inexperience and two young boys I fear somebody getting hurt by the boom....just out of sheer inexperience.

Would it be difficult to set up a sprit sail on the GIS? I realize it would cost some performance but a lug rig could be fitted later could it not?


Thanks,

Murray

Boatmik
23rd September 2007, 01:22 PM
Howdy,

I really, really don't like boomless sails.

There is an argument for them in rowing boats where a small, simple auxilary sail is be be added. The prime use is not sailing and the whole thing packages away very easily. Oughtred is a user of this type of rig for this purpose - and it is a very good choice.

But for a good sailing boat they are a very poor solution.

A boom like the one on the GIS is quite light and small (1 3/8" diameter if I remember) and in the body of the boat is quite high up compared to the floor of the boat - the GIS is extraordinarlily deep in the hull - but it is camoflaged by the curve of the sheerline and the pretty lines of the hull. Also the balance lug rig is very docile and unlikely to do anything sudden.

The only place boomless rigs work well is with certain catamaran rigs where the boat is wide enough for there to be a curved traveller to keep the mainsheet at the correct angle to the foot of the sail at all times.

The main problems are to do with the sail twisting heavily when the sheet is eased.

Upwind - you get a gust that threatens to overpower the boat. The natural response is to ease the sheet. The bottom part of the sail immediately becomes much fuller producing MORE power rather than less.

Reaching - The top of the sail twists out at a crazy angle reducing the projected area - less area to "catch" the wind - so much less speed. Also the sail shape is unstable and will twist further with every gust - the rig "bounces areound a lot. This reduces reaching performance substantially.

Running - when the sail is well eased for running the top of the sail can swing forward of 90deg to the boat reversing the heeling forces. So you get a gust and the boat heels to leeward initially but a bit more wind and it suddenly reverses - leading to a heavy roll every time a gust hits.

Also you are much more likely to do an unintended gybe because the bottom part of the sail is much closer to the centreline than would otherwise be required - making it easy for a small wind direction change or steering change to allow the wind to get in behind the bottom part of the sail and flip it over.

There are people who talk about "Performance" of boomless sails - but it is the "sales pitch" getting a bit past the theory and practice of sailing. Or they just haven't done enough comparitive sailing tot know!

The biggest single performance and safely enhancement in racing boats in the last 60 years has been the boomvang to reduce the twist and shennanigans I talk about above. Every racing boat has one and every successful racing sailor uses it - quite hard at times to hold the boom down.

The balance lug rig gets the same effect from its basic setup so there is no extra cost or complexity in keeping the boom down.

(I hope I didn't sound like I was being grumpy at you :-) The grumpiness was directed at those who push boomless sails. I will put them on some boats - but they do have serious drawbacks.

I have retrofitted a boom on several boomless rigs (the first one was a Murray Isles "Swallowdale" and ince little rowing/sailing hybrid) for various clients over the years and all have been very pleasantly surprised about the improvement in handling and performance.

Best wishes
Michael Storer

25th September 2007, 04:53 PM
Michael,

Thank-you for your long and informative reply. It really was most helpful. My kids are just going to have to learn to keep their heads down when changing course. (I also just came back from a performance by the Shaolin monks and after watching them break iron bars and wooden poles over their heads I have a greater appreciation for what sort of blows the human skull can withstand.)

I will be downloading a set of GIS plans in the near future. Thank-you very much!

Best regards,

Murray

Boatmik
26th September 2007, 11:38 PM
The first three kung-fu lessons are free!

MIK

27th September 2007, 12:32 PM
After three lessons they should know enough to duck!! :U I hope I learn that quickly!

I downloaded my GIS plans today and managed to find a few minutes during work to call around to track down some marine plywood.

The middle of the Canadian Prairies isn't the best place to look for marine plywood....There is one place in town that has marine plywood and all it has is Douglas Fir "marine grade" sheets.

Is this ok to use or should I try to find a source for Okoume plywood?

Thanks, Murray

Boatmik
28th September 2007, 06:05 PM
sorry about being slow to answer this.

Fir ply tends to check (crack) on surfaces over time. Gaboon or just about anything else is better.

Michael

1st October 2007, 05:50 AM
Michael,

Thanks again for the advice and help. I'll track down another source.

Cheers,

Murray

bitingmidge
1st October 2007, 06:41 AM
Murray,

Welcome, and don't forget to post pics! :D

P
:p

Boatmik
15th November 2007, 01:24 PM
I have put a building sequence with notes for the GIS up on Flickr
http://www.flickr.com/photos/boatmik/sets/72157602972202430/

http://farm3.static.flickr.com/2338/1504568362_0e88a4d5ef.jpg

Actually it is all the pictures from the Duck Flat Spring School and I have separated out the GIS ones so you can follow the narrative.

http://farm3.static.flickr.com/2233/1538798633_84908583b1.jpg

I have also gone through and written comments about each of the major steps.

So most of the hull construction is covered as is some of the hollow box section mast. There is a round solid one for those who like a dose of tradition!

http://farm3.static.flickr.com/2218/1520186977_9655b877c8.jpg

Michael

robhosailor
16th November 2007, 10:04 PM
Great boat and great photos of build sequence :)

It's very helpful for builders :)

bitingmidge
10th February 2008, 08:32 PM
I've finally updated my GIS website (http://www.peterhyndman.com/GIS/), with a bunch of new photos, a better build description, a few movies and all photos are now clickable to open as a larger size in a new window.

I'd love any feedback, broken links, or typos or whateve!

Thanks,

P
:D:D

m2c1Iw
10th February 2008, 10:03 PM
I'd love any feedback, broken links, or typos or whateve!

Hi Midge,
Couldn't find any whateve!'s :q, nor typo's but then thats in the people in glass houses basket and tried the links they all worked.

So as for feedback :2tsup::2tsup::2tsup: both entertaining and informative.

Only one problem I wanna build a GIS and its all your fault.:D

Cheers Mike

Theodor
11th February 2008, 11:29 AM
It seems to me that the index down the right hand side makes the pages extremely long. For example, the 'exceeding expectations' link fills about 2 pages of text, then I have another dozen or so pages which are blank. Not sure what is happening there.

Its certainly inspirations stuff! Nice site.

SOLing
11th February 2008, 11:33 PM
Hello you down under! I try to get used to all the different mails, blogs etc. about th GIS, but now I found this site!:)

A few weeks ago I bought the plans for th GIS and last weekend I started building it.

Reading the instructions, I came up with a few questions, mainly due to my lack of knowledge of boatbuilding terms in English / Australian, I guess.:?

Can I sent the questions to this site?

Also I will keep a blog on the progress. Maybe it can be connected to the GIS site?

I make a lot of pictures of the building of the GIS (some 5 of each step) . If any of you you are interested, I can change them into another format (right now: RAW, some 3 MB each picture) and size.

Hope to hear from you soon


http://image-mirror.cyanide.com.au/woodworkforums/images/statusicon/user_online.gif

Boatmik
12th February 2008, 01:47 AM
Hello you down under! I try to get used to all the different mails, blogs etc. about th GIS, but now I found this site!:)

A few weeks ago I bought the plans for th GIS and last weekend I started building it.

Reading the instructions, I came up with a few questions, mainly due to my lack of knowledge of boatbuilding terms in English / Australian, I guess.:?

Can I sent the questions to this site?

Also I will keep a blog on the progress. Maybe it can be connected to the GIS site?

Hi SOLing - if you like there is an option to put the building story up here. Then the questions (from both you and us) become a permanent part of the whole thing.

The only real limit is that if you want to have the images on this site they have to be smaller than 800 x 600 pixels and smaller than 100kb. See the "manage attachments" button below the window when you post a reply to this.

The other way is to have them some place like flickr and put in a link.

eg - this is one of my picture sets on flickr
http://www.flickr.com/photos/boatmik/sets/72157602972202430/

And this is one of the images - they give you a choice of around 5 sizes. This is the medium one.
http://farm3.static.flickr.com/2133/1503720547_0ce2a1e0ec.jpg

If you want other people to see your post this is one of the best places. Some of the building stories have had big numbers of readers. Though there are other places on the net like this too.

But you would be welcome if you want to do it here.

Just start a "new thread" and call it what you want. I can correct things if you have any difficulties.

Best wishes
Michael

Boatmik
12th February 2008, 01:50 AM
Now, SOLing ...

May I ask - why are you are called "SOLing".

(they are a great boat! But there may be another reason)

Best wishes
Michael

SOLing
12th February 2008, 06:00 AM
Hello Mike,

thanks for the welcome!

my name is SOLing for at least tw reasons:

SOL as for sun , because every time I think about boats sailing knots etc I feel sunny inside (my wife thinks I am a bit crazy. I guess she is right in this respect).

The second reason is for the soling indeed. the best boat i have sailed in, al though at that time the weight of the crew gave us only an advantage in very light winds. That has changed, now we would be best at a force 5. But no longer a soling in sight:no:

I will start a thread and move the content of my blog there: to maintain two sites will be too much.

The questions I will do in another thread

kind regards

ab

robhosailor
12th February 2008, 08:02 AM
I've finally updated my GIS website (http://www.peterhyndman.com/GIS/),

Great website!!!
I like it!

Boatmik
12th February 2008, 12:05 PM
Hello Mike,

thanks for the welcome!

my name is SOLing for at least tw reasons:

SOL as for sun , because every time I think about boats sailing knots etc I feel sunny inside (my wife thinks I am a bit crazy. I guess she is right in this respect).

The second reason is for the soling indeed. the best boat i have sailed in, al though at that time the weight of the crew gave us only an advantage in very light winds. That has changed, now we would be best at a force 5. But no longer a soling in sight:no:

I will start a thread and move the content of my blog there: to maintain two sites will be too much.

The questions I will do in another thread

kind regards

ab

Howdy Soling - I used to race a Soling when I was a teenager (and we sometimes won races when the helmsman did particularly well (or listened to me)). They were never really common in Australia. The great thing was that the owner let me take the boat out by myself - so I could use it whenever I wanted. Not a bad thing for a 15year old.

He then upgraded to an Etchell - which he was very proud of - so my school holiday sailing fleet was reduced in size.

With the forum...

It would be great if the questions were in the same thread as the building - that way people can see the relationship of the questions to the building.

Have a look over the Eureka and the PDRacer threads and you can see how they grow in a natural way - with building stuff, questions from the builder and the people who drop in.

But please don't feel any pressure - just do what you would like and we can help it as best we can.

Best wishes
MIK

koala
5th March 2008, 06:23 AM
Hi

I have a question re. building a mast, boom etc. for either a GIS or PDracer.

I know that wooden mast/boom would look better but since I would need to buy all the material anyway and plane down all the wood somewhere - and if I ask the carpenter to do that for me it cost more- aluminum then is not that expensive.

So I was wondering, what kind of aluminum tube would I need for mast and boom for:
a) GIS and
b) PDracer

I can get the tubes anywhere from 20-80mm and wall thickness 2; 2,5 and 3mm.

Thanks

Boatmik
5th March 2008, 12:54 PM
Howdy Koala,

This is a bit of a problematic area for me. I know aluminium can be so much easier and lighter for the overall weight of the spar (it can be heavier at the top though), but there are two big problems and one smaller problem.

1/ It cannot compare for performance - the bending characteristics of the PDR mast and the GIS Lug Yard in particular are responsible for a very large part of the sailing performance of the two boats.

The bending when a gust hits the boat is just right to prevent the boat heeling too much and allows it to accelerate rather than stalling.

This effect is the single most important improvement in sailing boat performance in the last century.

So I make use of it in all my boats - just like a well tuned raceboat.

Using aluminium would require a bit of trial and error to get something like the same response.

The PDR mast would have to be of two different sections like a Laser mast - a thick one at the bottom and a thinner one about halfway up. The lower one to be strong enough and the upper one to be flexible. Then you have to join them and make sure the change doesn't affect the shape of the sail.

2/ Aesthetics - untapered aluminium masts look really bad. If you used a thin and thick tube for the mast on the PDR it would be acceptable in appearance.

But for the Goat which is such a beautiful boat it would look terrible as the mast is quite big at the base and if it goes to the top. For the Goat Mast (and all lug rig masts) it is only the appearance that is the problem as that big stick is not supposed to bend much.

And the lug yard and boom look nice too when tapered. Pic below.

http://farm1.static.flickr.com/131/379093468_a0ff12b8e3.jpg

This pic (the best I could find) shows how the taper of the mast matches the thickness of the yard at that point keeping everything in nice proportion - it keeps the feeling that it is continuous.

http://farm1.static.flickr.com/146/379074785_354029c752.jpg

TOUCHDRY
26th March 2008, 03:52 PM
Hi

I have been looking at the GIS as an option to build this winter. I realise this question is one of those 'how long is a piece of string' questions, but what is a ball park cost of materials (including timber and rigging)? In short- How much could I get it on the water for, do you think? Having never built a boat (but worked plenty with wood), I'm on a learning curve with the cost of marine ply and gear etc.

Boatmik
31st March 2008, 11:33 PM
Howdy Touchdry,

Don't go for a ball park figure - get a quote. Email or phone the Duckflat mob.

You can get contact details from
http://www.duckflatwoodenboats.com

They have it all worked out in a spreadsheet.

I know I'm being a bit of a party pooper taking the mystery and discussion out of it - but it's the sort of thing I do.

Be aware that you don't necessarily need to get the whole lot straight up.

Michael Storer

TOUCHDRY
2nd April 2008, 04:20 PM
Thanks!

paulie
11th April 2008, 04:48 AM
Hey, all. My kids and I are planning to build a GIS this summer (that's Northern Hemisphere summer, starting in a couple of months). I bought the plans from Duckworks last week and I've been studying them carefully. I am extremely pleased with what I see.

One of the main reasons (other than the fact that it is beautiful) that I chose the GIS over other designs was the light hull weight. We plan on building a dolley and pulling the boat by hand back up to our house after each use. The standard racer class around here is the 420 -- it's what I raced as a kid and what my own kids are learning on -- so we originally thought about buying a used one. But when we thought about its 100kg hull weight (for 0.5m less LOA!), we decided to look for something lighter.

But now I'm torn. The plans mention the option of glassing the whole bottom if the boat will be used on a rocky shore. Our beach is sandy but has rocks poking through. And there are many sharp rocks just offshore which lurk just below the surface at low tide. I don't want to become the crazed psycho-dad screaming at the kids to be careful of scratches. I want them to enjoy the boat. So I'm thinking about glassing the bottom for abrasion protection.

So, my questions are: About how much weight would this add to the hull? (5kg? 10? 15?) And would it add enough protection to be worth it?

Thanks in advance.

Boatmik
11th April 2008, 09:33 AM
Hi Paulie,

A few rocks for people who are used to handling boats are usually not much of a problem. So if you are used to launching a racing 420 from the same place without being too concerned, then the GIS will be fine too.

The glass does add quite a lot of weight relative to the plywood - simply because plywood is so light in comparison. Glass laminates are is more than 3 times the weight of wood for the same thickness. If you start to look at lightweight timber like the gaboon/okoume it is possibly getting up to 5 times the weight.

Suddenly the 100kg of the shorter 420 starts to look less heavy! How did they make it so light using a heavy material like fibreglass!? (the reason is that they accept a lot more flexibility in the hull panels which make the boat slower than a wooden version).

However, if you sleep on it a few times and think you still want to glass I would suggest only do the bottom panel of the hull. And use the lightest weight glass possible.

Instead of using the 6oz glass (200gsm) that most people use some 2oz (75gsm) and the weight gain will be much less. You could use lighter. You can mail order it as the quantity you need would be quite postable.

Glass gives protection largely because it is much harder than wood. And if the surface is hard it probably doesn't matter how thick the glass is from a protection point of view.

So if, on reflection, you think it is necessary then just use a very light woven fibreglass cloth.

I've had lots of plywood boats and I have had little damage other than paint scratches from rocks - however if your local beach is really bad then it might be worth considering a light layer of glass.

Remember too that lightweight in a wooden boat is because of the general materials - so if you try to select lightweight materials it removes a lot of weight.

As you are in the USA I would strongly recommend Western Red Cedar for all the internal framing as it is nice and light, not too expensive and readily available (?).

You can use it for the gunwales too as they are capped with a piece of something harder on the outside. It is great for centreboards and rudder blades - but make the front and rear pieces of something slightly stronger (fir/spruce something like that).

That actually is a great weight saving strategy - make the body of a part out of a lightweight timber, but protect it where it might get bumped or dragged with a thin lamination of something tougher (but not toooooo heavy)

The mast could be made of spruce. The square hollow mast is the best choice for weight saving.

If you and the kids have a background in 420s you will find the GIS a very rewarding boat to sail. It might even be fun to enter it in some open regattas - send the organisers a photo - and they will give you a very favourable handicap - "lug rigs are slow" "oh - and it has a flat bottom - who would design a boat like that".

I have done that a number of times with my BETH sailing canoe (same perceptions - plus "oh, it is surprisingly pretty but ketch rigs are not efficient").

It is a lot of fun when I can match an average Laser for speed! Ensures good regatta results - the first time anyhow.

The right plywood makes a huge difference in weightsaving too.

Best wishes
Michael

paulie
11th April 2008, 01:37 PM
Michael,

Thank you for the quick, thoughtful, and complete reply.

Did I mention that I think the GIS is beautiful and that I'm very impressed with the plans? I looked at a lot of designs before making my decision. I choose the GIS in large part for its beautiful lines.

Based on your reply, I think that we will build the boat as spec'd and forget about glassing the bottom. It sounds like a lot of extra weight for marginal gain.

Scratches in the paint don't bother me -- any well-used boat will earn a few scars. My real concern is scratching through the epoxy and allowing salt water to soak into the plywood underneath. We'll just have to be careful when launching and beaching and repair anything that looks too deep. And I'll try my best to relax about it and not ruin the kids' fun with my worries!

Thanks also for all the info about materials. I'm just starting to make phone calls now to suppliers. I hope to have all the materials in hand before the kids are out of school so that we have no delays once we start.

Daddles
11th April 2008, 04:47 PM
Scratches in the paint don't bother me -- any well-used boat will earn a few scars. My real concern is scratching through the epoxy and allowing salt water to soak into the plywood underneath.

When Redback first hit the water, I was touching up scratches everytime I used her, just a matter of slopping some paint on after giving her the after float wash down - easy to do since she lives upside down. After some months, the enamel finally hardened and it's become less of an issue. I wouldn't worry about it mate, just be ready with the paint pot until you finally realise you're wasting your time.

Richard

Theodor
12th April 2008, 10:39 PM
I had thought about glassing the front bottom of my (future) GIS as well since the beaches around Slovenia and Croatia mostly look like pictures below - yes it is beautiful, clear blue sea but nasty rocks on the beach.

This is obviously a question for the future when the boat is being built, but if the coast is like this (i.e. no sand at all), doesn't it make sense to glass even though a little weight is added?

Cybernaught
13th April 2008, 09:21 AM
Hi Theodore,
Not sure how it would work but if you put skids on the bottom about 1 inch deep by 2 inches wide and then put flattented copper tubing on top of that the copper would take most of the punishment. Stailess or aluminum should work too as long as the metal is tough, faily cheap and non rusting. Not sure how that would affect the sailing characteristics of a GIS though. Probably add weight and drag. Perhaps sheeting with kevlar??? Sounds expensive though. Good luckl

Your local beaches there look like they'd raise hell with most boat bottoms. Not as bad if the rocks are smooth and rounded but far from ideal.
Conditions may vary but sailing still remains the best pastime there is. (BTS)
:U

Enjoy,
CN

Daddles
13th April 2008, 11:37 PM
Redback's got two 1cm square strips of hardwood on her bottom (plus a hardwood facing on her keel). The paint still gets knocked around but the worst of the damage is taken by the hardwood rather than the ply. Worth a thought?

Richard

Boatmik
14th April 2008, 05:07 PM
Howdy Theodore,

For a beach made of pebbles I would recommend glassing even with the additional weight.

You could use brass strip or put hardwood on the skids - still do mostly of light softwood but put a 6mm thick layer of a heavy, strong hardwood on the bottom edge.

I would not suggest the copper tube - it might be cheap and available but it would be quite ugly and the goat is such a pretty boat.

Michael

Theodor
14th April 2008, 09:36 PM
A hardwood strip on the skids makes sense .. nice idea. I will plan for glassing the bottom as well.

Since Koala is keen to make some PDRacers first, we'll experiment on those first.


Cheers,
Theodor (no final 'e' and I have no reason for that)

Boatmik
15th April 2008, 02:37 PM
Sorry about the "e" Theodor!!!!

The hardwood only needs to be quite thin - 6mm is enough

Michal

Theodor
15th April 2008, 07:47 PM
Sorry about the "e" Theodor!!!!

The hardwood only needs to be quite thin - 6mm is enough

Michal


I wouldn't worry about trying to get an internet alias correct (especially when you can't spell your own name :D). I'm not entirely sure why I'm using that name!

Boatmik
16th April 2008, 09:33 AM
Some craziness is a good thing!

It is not too good when the world becomes a completely rational place!

MIK

Daddles
16th April 2008, 09:59 AM
Some craziness is a good thing!

You mean it's optional? :oo:

Richard

larson50
23rd May 2008, 03:55 AM
Ok, great boat. Bought the plans, and now found this Forum!

I am looking at building the GIS with the bottom out of ½ in rather than ¼ in, for two reasons:
1. Lots of mass in those that will be in the boat, and don’t want to put a knee or elbow through it easily, and;
2. I have two sheets of 4 x 8 ½ in marine ply already.

I am also looking at cutting the transom out of one of the ply, thus the bow for the bottom will need to be two triangles cut from other ‘scrap.’

Anyone see any problems with this? (Beside the weight issue)

Glen

Boatmik
23rd May 2008, 04:48 AM
Howdy Larson! And Welcome!!!

You really won't need the extra thickness. Half Inch is way overkill - it will end up weighing the same as all those other boats that you didn't buy the plans for!

12mm will be Eight times stiffer than 6mm. Not double - but eight! and the chines - the only place it can possibly break will be the same size anyhow (but they won't break either)

Nice thing about the Goat is that built as per the plans it is a reasonable weight for two adults to handle on the shore. Increase much at all an it all becomes a big chore.

And of course the sailing performance won't be the same either.

If it makes the difference between building or not building the boat then go for the thick stuff - providing the rest is the plan spec. But if you want a thing less ordinary - build it as per the plan.

Best wishes
Michael

bitingmidge
23rd May 2008, 08:55 AM
I am looking at building the GIS with the bottom out of ½ in rather than ¼ in, for two reasons1. Lots of mass in those that will be in the boat, and don’t want to put a knee or elbow through it easily, and;

Glen,

To satisfy yourself, fix a piece of 1/4 ply to a timber frame about 18" square (that's more than the biggest span on the GIS), put a pair of steel capped boots on, and TRY to kick a hole in it. DON'T do it with elbows, you'll break bones.

When the ply is contained by the structure, it is immensely strong, and there's no risk of it puncturing from a human falling on it!

I agree entirely with Michael regarding the weight too, you may not be disappointed, but you'll never know what you are missing out on.

Cheers,

P
:D

Christopha
23rd May 2008, 02:14 PM
I love the pics and video of her sailing but do you have any of her being rowed or motored? and how many hp? She appeals.... and the GF says she doesn't want to sail on her own so a GIS is looking better than 2 PDRs'....
Hell I wish the shed was happening. :(

bitingmidge
23rd May 2008, 04:05 PM
Dave's boat was used for a year or two in this configuration before he built the rig. He may pop in and correct me, but I think he had a building project on one side of the lake and it was the barge? Mik?

http://www.storerboatplans.com/GIS/gisgraybeal6.jpg

I don't have any pics rowing, but use a pair of 9' oars and it rows very easily. I used to (haven't for a while) row regularly from our place for about half a mile to a low level bridge, once under it I'd rig and go sailing out in deeper water. It's all a bit of good fun really. Usually I carry a couple of others with me and it's no effort at all.

Mik's done that solo a few times too, he may care to comment from his perspective.

Cheers,

P

Boatmik
23rd May 2008, 05:27 PM
As far as the robustness of the GIS's bottom you might like to read this from my web pages.
http://www.storerboatplans.com/GIS/GISplan.html


Can the GIS carry a load?

From Leigh Hemmings on Scotland Island

Dear Michael,
Hi, from Scotland Island.Today we used our light fast and pretty Goat Island Skiff as a concrete, blue metal and sand barge. Previous days have seen it used as a timber barge -- powered by an electric outboard!. When not in this guise it's main role is our commuter boat. But, once our renovation is a little further down the track, our Goat Island Skiff will once more become light fast and pretty sailing craft. Trust you are well and enjoying life.

More on Motoring

The boat balances quite OK if there is someone else in the boat to sit on the front seat with the driver on the rear seat. When by yourself the boat will balance better if you make up a tiller extension for the outboard so you can sit on the middle seat.

A tiller extension for the outboard can be made of plastic pipe to fit over the outboard tiller.

What sort of Outboard works OK

Not too big - you won't go any faster and it might put too much load on the boat.

Perhaps you can use a slightly larger outboard, but generally outboards don't take too well to running at low revs all the time - and it is another heavy bit to carry round.

Be aware too that outboard weight is a whole field to itself. Generally a manufacturer will use the same engine as the basis for 2 or 3 models. So you may see an three different horsepower outboards all with about the same weight - ie they all use the same block and other internals.

So do some checking before buying.

Daddles
23rd May 2008, 05:58 PM
Be aware too that outboard weight is a whole field to itself. Generally a manufacturer will use the same engine as the basis for 2 or 3 models. So you may see an three different horsepower outboards all with about the same weight - ie they all use the same block and other internals.

So do some checking before buying.

That's why I've got a 5hp for Sixpence, it was barely a kilo heavier than the 3hp despite looking twice the size. Mind you, it helped that David Payne specifies the 5 hp Yammy long shaft, the same motor I bought :wink: ... about 2 years ago :-

Richard

Boatmik
23rd May 2008, 06:16 PM
Be aware too that outboard weight is a whole field to itself. Generally a manufacturer will use the same engine as the basis for 2 or 3 models. So you may see an three different horsepower outboards all with about the same weight - ie they all use the same block and other internals.

The more cynical exercises of the type just had a little lug in the throttle twist grip or its linkage or on the side of the carby that limited the motion of the throttle.

Remove the pin and you could turn a 6 into a 9.9 or a 9.9 into a 15.

I believe motorcycle fiends turn this into an artform - anyone want to get a moped up to 100kph?

MIK

CCBB
23rd May 2008, 08:47 PM
The Torqueedo electric outboard would be a great fit for a family in a GIS

http://www.torqeedo.com/us/hn/products/travel/product-description.html

Any one tried it?

RE: Robustness of bottom> not cheap but some folks in the Pacific Northwest laminated Kevlar onto the bottom of their dories for ultralight abrasion resistence of the bottom plank. I've never laminated with Kevlar.

Last summer I became a yawl advocate after a local Raid event at Woodenboat. I think the mizzen makes life very simple. What about adding one to the GIS, offset of course...just a small 9-11 SF or so one that will get the boat to point into the wind, heave to when necessary. I'd envision the mizzen to be used for longer sails or with new crew to help "park" the boat to deal with issues, reef underway, or just have a drink. Maybe you guys could comment on a mizzen. It'd add no weight to the hull...should change the CE negligibly, I would think with it being such a small mizzen.

Cheers,
Clint

Boatmik
24th May 2008, 08:53 PM
Kevlar is awful to handle - the midge once built a 30ft cruising racing cat of the stuff.

I've used a bit and it is a pain - hard to cut, hard to wet out, impossible to sand.

Exactly the qualities you need to avoid abrasion. But it is massive overkill.

If you have mostly sandy beaches or soil and grassy edges - no problems ever. Concrete ramps are no problem either - particularly if you put some brass strip on the bottom skids. Midge did that with Gruff and geez it sounds awful when this beautiful timber boat gets dragged up a concrete launching ramp!!!

If your shores are rocky then my feeling is light glass does almost as good a job as much heavier glass - but remember that most goats have had no glass. The epoxy coating is enormously flexible and can handle all sorts of knocks without cracking and seems to stop most surfaces from "digging in".

We have been using 2oz (75gsm) for some boats where the plan specifies 6oz and found that it provides an awful lot of protection.

As far as yawl GISs. I like yawls too (refer Beth), but two sails would add about 60% to the cost of the existing rig - and the GIS is very stripped out - I have taken pains to keep stuff out of the boat. Which is why it is so light and has so few pieces.

Also adding a mizzen means the centreboard has to move further back or the main mast move further forward. Both are bad choices.

One will make the boat pitch more in waves - at the moment it is quite OK because the pitching from the mast being in the bow is damped adequately by the flat bottom (that's something people never mention when they worry about whether flat bottoms work - even catamaran design is heading the same way with much flatter sections under the bows - mostly to damp pitching as well) and moving the centrecase moves the seat too far back forcing the crew too far back in the boat. REally bad for performance.

Could do it starting with a clean (metaphorical) piece of paper - but the goat is a goat is a goat.

best wishes
MIK

Boatmik
24th May 2008, 09:11 PM
Torqeedo looks like a nice unit

Reviews
http://www.whitehallrow.com/enews/mar_2007_enews.php
http://www.trailerboats.com/output.cfm?id=1197955&sectionid=315

This one is also positive, but I find the claim doubtful. He is using the torqeedo on a 35ft yacht (a light and narrow one for sure, but still 35ft) - I think he is talking about zero wind conditions. Against a wind and sea I suspect he would be sailing. But there is a review on use on an inflatable at high speed and low speed which sounds quite believable in terms of drain.
http://listserv.aol.com/cgi-bin/wa?A2=ind0709a&L=nonsuch-l&T=0&P=4107

MIK

Christopha
25th May 2008, 02:38 PM
Michael, with the price of fuel going through the roof at the moment, especially for those of us who live in the country, a boat like the lovely GIS whch can be used under sail or with a small outboard looks more and more appealing. As her designer, what horsepower motor do you recommend? What changes need to be made to the boat to accept a motor? I don't know how she would go when pulling the cray pots but she looks as though she wouldn't be too bad for sneaking around for a few Sweep and she appeals as camp/tourer for the Murray where a shallow draught is getting more and more essential.

Boatmik
25th May 2008, 07:30 PM
Howdy Christopha,

Nice to run into you again! I'd be very surprised if you could use more than just a couple of horsepower on the goat. Leigh Hemmings who sometimes uses his as a gravel barge (!) generally gets by with a 2.5 or 3hp four stroke (I almost typed three stroke). Much more and efficient low speed hullforms want to stand up on their tail. You can see this a bit on pic above (transplanted to here)

http://www.storerboatplans.com/GIS/gisgraybeal6.jpg

The pic is one of my USA builders for the Goat David Graybeal. Even a couple of horsepower can be pretty effective - you can do 3mph in a calm with oars quite easy. So the mechanical horse will do a lot better.

In general I would probably not think of sailing with the motor on the back. It would probably be safe ... but ...

And it would raise the centre of gravity a bit - and it would already be up with the mast in place.

Best wishes
Michael

CCBB
27th May 2008, 10:53 AM
Could do it starting with a clean (metaphorical) piece of paper - but the goat is a goat is a goat.



Yes, I understand completely.

Christopha, RE: changes to boat, Mik shows a plywood pad on the transom for reinforcement where the motor clamps on...only mod I observed and the usual one made to transoms taking an outboard. Check out those torqueedos!

Cheers,
Clint

Boatmik
27th May 2008, 12:22 PM
Howdy,

The transom, though it is quite thin is heavily braced by the top stiffener and two big knees. It also has the rear seat supporting the middle section. The stiffener up the middle is just somewhere to clamp the outboard (David Graybeal put it to the side) and also to transfer load between the stiffener and the rear seat.

MIK

paulie
29th May 2008, 08:01 AM
I have nothing of value to add to this discussion, but I had to post anyway.

DHL just dropped off a box of epoxy and tape from Duckworks. I've got confirmation that my sail is being made (also by Duckworks) and will be available within a few months. I've found a local source for high-quality Greek okoume ply (US$110/sheet due to the recent fall in the US dollar -- ouch!!). And I've cleared space in my garage for the build (a monumental archeological undertaking involving several days of work and multiple trips to the dump).

In short, by the time my son is out of school in a few weeks, we should be ready to begin construction on our GIS. I can't wait.

Boatmik
29th May 2008, 10:32 AM
Howdy Paulie,

I think we have a different definition of a contribution. Your post looks like one to me!

Thankyou

MIK

CCBB
8th June 2008, 02:19 PM
Keep us posted, Paulie.

Cheers,
Clint

paulie
14th June 2008, 12:04 PM
Michael,

With our projected start date almost upon us, my lumberyard has suddenly discovered that some of the materials I ordered will be hard to get.

Specifically, they are concerned about all of the 5.1m lengths. They want to know if any of those lengths can be made up of shorter pieces scarfed together. I assume that this is impossible for some parts (e.g., the inwales and the fairing batten). But is it possible for gunwales (assuming I offset the joints) and chine logs? Is it possible on the rectangular hollow mast (again assuming I offset the joints)?

The yard was also iffy on the availability of western red cedar and asked if white cedar would do. Not knowing the difference between the two, I told them I'd have to pass the question on.

Of course, I can always try other lumberyards. Mystic Seaport is just an hour up the road. There are several yards up that way which specialize in material for wooden boats. I'm sure that one of them will have what I need. But I was hoping to avoid starting a new search with so little time left, especially as I'll be out of town for several days next week.

Thanks, as always.

Boatmik
14th June 2008, 01:35 PM
Scarfing is no worrie at all Paulie. Read the section in the appendices about gluing endgrain and use a minimum 6:1 scarf.

The red cedar was specified because of its lightness. The white cedar is not particularly light - it looks like it around the same weight as fir. See if the local yards have something light that glues well otherwise use the white cedar or fir for those bits.

A decade ago we used to get heaps of Fir (Oregon pine to the locals) and Western red cedar from the USA and Canada for the housing industry. Boatbuilders could pick through the construction grade stuff to find fantastic old-growth timber to build their lightweight flying machines.

No more - and it is a good thing - makes it more difficult to build refined boats though. Though in OZ we are starting to see plantation grown Paulownia (sometimes called Kirri) - which is lighter than cedar - straight grained and good to glue. It would be a great substitute for any of the cedar bits in any of my boats. The Chinese use it for windbreak forests as well as growing it for timber.

Here are some links to a number of North American species and their properties
Softwoods (white pine looks like a possible if knot free-ish.

Amabilis Fir (Species Mix: Hemlock-Fir) (http://www.bcforestinformation.com/wood-products/tree-species/amabilis-fir.aspx)
Douglas-Fir (Species Mix: Douglas-Fir-Larch) (http://www.bcforestinformation.com/wood-products/tree-species/douglas-fir.aspx)
Lodgepole Pine (Species Mix: Spruce-Pine-Fir) (http://www.bcforestinformation.com/wood-products/tree-species/lodgepole-pine.aspx)
Ponderosa Pine (http://www.bcforestinformation.com/wood-products/tree-species/ponderosa-pine.aspx)
Sitka Spruce (Coast Sitka Spruce) (http://www.bcforestinformation.com/wood-products/tree-species/sitka-spruce.aspx)
Subalpine Fir (Species Mix: Spruce-Pine-Fir) (http://www.bcforestinformation.com/wood-products/tree-species/subalpine-fir.aspx)
Western Hemlock (Species Mix: Hemlock-Fir) (http://www.bcforestinformation.com/wood-products/tree-species/western-hemlock.aspx)
Western Larch (Species Mix: Douglas-Fir-Larch) (http://www.bcforestinformation.com/wood-products/tree-species/western-larch.aspx)
Western Red Cedar (http://www.bcforestinformation.com/wood-products/tree-species/western-red-cedar.aspx)
Western White Pine (http://www.bcforestinformation.com/wood-products/tree-species/western-white-pine.aspx)
White Spruce & Engelmann Spruce (Species Mix: Spruce-Pine-Fir) (http://www.bcforestinformation.com/wood-products/tree-species/white-spruce-and-engelmann-spruce.aspx)
Yellow-Cedar (http://www.bcforestinformation.com/wood-products/tree-species/yellow-cedar.aspx) Hardwoods


Red Alder (http://www.bcforestinformation.com/wood-products/tree-species/red-alder.aspx)
Bigleaf Maple (http://www.bcforestinformation.com/wood-products/tree-species/bigleaf-maple.aspx)
White Birch (http://www.bcforestinformation.com/wood-products/tree-species/white-birch.aspx)
Trembling Aspen (http://www.bcforestinformation.com/wood-products/tree-species/trembling-aspen.aspx)

Best wishes
Michael

Boatmik
14th June 2008, 02:03 PM
Hey PAR, Paul, where are you?

Can you help here? What I generally do with my plans is that I specify three levels of wood for the construction - all of which were formerly available in OZ, but are not even that available in their native countries now.

Anyway ... specified ...


Spar grade Oregon Pine (Fir with a fine grain) - now completely unavailable in OZ.
Oregon Pine (Douglas Fir in the USA) - as the main timber for high structural loads and lower loads where something might get bumped around a bit - eg gunwales etc.
Western Red Cedar - for internal chines and cleats - it is lighter than the fir, glues just as nicely and saves quite a bit of weight.
Hardwood - just a generic for bottom skids or protective laminations on the outside of gunwales etc.


I continue to use these names but have reframed them as generics - that the timbers serve a different function and suggest some options.

Can you suggest some alternatives for each group that are available in Nth America within the ply and epoxy built boat scenario (I know you do much more than this)? Would be extraordinarily grateful.

Cheers
Michael

paulie
14th June 2008, 09:38 PM
THANK YOU!

You've just saved me hours of time on the phone plus a ride in a gas-guzzling truck to a distant lumberyard. This info will get me back on track.

I've got a carpenter buddy and the lumberyard owner going over the substitution list to see what is readily available locally. I will post back our final choices to you can add them to the knowledge base.

Thanks again.

PAR
14th June 2008, 09:57 PM
Okay Michael, but it's subject that easily could be a book (or two) if especially comprehensive.

There have been some changes in North American supplies in recent years, most having to do with fast growth hybrids and lesser quality native species being passed off as the lumber of old.

Specifically, there's a product (I use this word intentionally, as it's an engineered species) called Hem-fur, which is hemlock crossed with fur. It's getting sold as Douglas fur and it's crap, rots at the mere mentioning of moisture and isn't particular strong for it's weight.

To identify this stuff the heartwood is light brown with a pink tint, the sap wood is difficult to distinguish from the heart, course, uneven grain, some shake in wider boards. It's about 26 - 28 pounds a cubic foot and is a weak wood for it's weight, has low rot, shock and impact resistance. Generally a bit of engineered junk wood that grows fast so it can make harvester's money.

Douglas fur has declined in recent years, but good examples can still be found if you know wood. Picking through a stack of boards, you'll run across a couple, that seem heavier then the others. Look these planks over and you'll see they have a much tighter grain pattern. This is the stuff you want. It's moderate to good at rot resistance, shock and impact (for a softwood). It works as well in structural applications but can be quite difficult to finish smooth. The grow ring have widely different densities, which when sanded will produce a washboard effect. No amount of sanding will remove this, just filler.

With sitka spruce becoming so prized (read costly) I've been using white spruce for small brightly finished spars. It's slightly lighter then sitka and has similar compressive, fastener holding and machining qualities. In larger sticks (say 35' or more) you should consider another species, Douglas fur if painted.

Western larch is about the same as Douglas fur in properties and is often sold as such. It's heavier and checks less (a well know issue with Douglas fur), but still checks, more then acceptable in finish applications.

Red Western cedar is a light weight relatively weak lumber that doesn't hold fasteners well. It's best suited for thin planking on small boats, used as veneer or in strip planking.

If I had to pick a cedar for structural applications I'd use Spanish cedar (or yellow cedar). It's heavier, denser, stronger and holds fasteners, plus has fine rot resistance.

Ponderosa pine is useless in boat building applications, except as picture frame material for hanging your better half's portrait on a bulkhead.

Lodge pole pine is basically another name for western larch.

Yellow cedar is a nice medium weight wood, very fine grained and exceptional rot resistant. It holds fasteners well, finishes very well and is quite strong.

Hardwoods are pretty simple, most of the white oaks. There are two basic oak groups in north America, white and red. Don't even think about any of the reds, they rot easily, aren't as strong as they should be for their weight and unless used as a deadwood assembly, in a large boat, which will remain on a mooring in salt water (where they will not rot) shouldn't be considered.

The white oaks (evergreen and live oaks are the other common whites) have wonderful qualities. So much so the British tried to cut it all down before they lost the war with the colonies. It's dense, heavy and very strong. I prefer live oak, as it has an interlocking grain and isn't as subject to checking like other hardwoods can be. The USS Constitution was built entirely from live oak and the very reason she got the nick name Old Iron Sides, as the British cannon balls literally bounced of her flanks (no wonder they tried to steal it all). White oaks can be tricky to epoxy well. I can do it, but I use special prep and thin laminations.

Ash and elm are very similar and make great beams. Good examples may be stronger then oak. It's less weight too, about 42 pounds a cubic foot. Elm is lighter and not as strong, but most folks can't tell the difference between the two. It wears very well and makes good countertops and cockpit gratings.

Southern yellow pine. Yep, it's a softwood, but in name only, it's tough stuff and a fine structural lumber. It has good rot resistance, holds fasteners and finishes well.

Locust is a good wood, very dense and strong. Tunnels were often made from it, as were cleats, belaying pins, etc. If you can find some, use it.

Maple is an interior wood, as it has poor rot resistance, but it's a pretty lumber. Furniture makers have prized it for generations.

Alder is called the great imitator because of it's ability to mimic other woods with some color matching. It bends very nicely and is often seen in those arched back chairs. It has little rot resistance so keep it dry.

Birch can be commonly found in plywood, but it too has little rot resistance. Embalmed in epoxy it's a pretty wood with good qualities.

Those in North America should download "FPL-GTR-113" from the US Department of Agriculture. This is the "Wood Handbook" and has the physical properties of most common domestic and imported woods.

I use live or white oak exclusively for bottom rub strips, runners, skid plates, etc. Live oak is especially well suited for these tasks, as is locust.

In the USA, plywood made in country to marine grade, will be Douglas fur or western larch. Most folks are opting for the imported stuff, such as Hydocore (mercani) or Aquacore (Okoume), which are fine products, if manufactured well.

millhavenguy
15th June 2008, 12:13 AM
While shopping at my local lumber yard (not a big box store) for plywood for my PDR I found a product called Radiata pine. It is virtually knot-free, available in lengths up to 16' long and up to 10" wide. It seems to take glue well. It seems quite light, perhaps not quite as light as WRC and while not as stiff as Doug fir I feel OK using it for chine logs as well as framing timber attached to bulkheads.

The stuff is plantation grown somewhere in South America, and while not as cheap as typical lumber yard SPF or Hem/fir it is cheaper than WRC or Doug fir. Also the idea of not using up precious old growth timber has it's own appeal.

Has anyone else used this stuff or thought about it?

David

b.o.a.t.
15th June 2008, 03:42 AM
radiata pine = Monterey pine
Heavy, low strength & abysmal rot resistance.
Can be treated with Copper-chromium-arsenide to make it very rot-resistant, but this doesn't help its strength or weight. Probably illegal outside australia anyway...
Extensively planation-grown in Australia & NZ as building / construction ply / pulp-wood. It's fast & cheap to grow, & tolerates heat/cold/dry.

There are many better choices for boat-building as per MIK's & PAR's lists above. I have a couple of bits in non-critical places on my Teal. The skeg is CCA treated & heavily glassed - weight & strength irrelevant. The untreated gunwale laminations are a constant battle to keep from rotting. :~

funnily enough, although regarded as a noxious weed species outside of plantations in Oz & NZ, http://en.wikipedia.org/wiki/Monterey_Pine says it is in trouble on its home turf... Bear in mind too that in many parts of the world, old-growth had to be cleared first to make way for plantations. In my opinion, selectively saw-logged forests can be the most sensitive way to go (if that is important to you). So much so, that land in SW Tasmania which had been logged by the Bradshaw family and other mill-loggers for over 80 years was declared "pristine wilderness" & locked up as World Heritage Area.

cheers
AJ

millhavenguy
15th June 2008, 05:51 AM
Hmmm.... sounds pretty crappy. They also had some plywood that is advertised as having Radiata pine inner plys with exterior grade glue. I wonder if it as bad as the dimensional stuff?

Thanks for the heads up!