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Tomahawk J
8th May 2008, 01:25 PM
I know I'm jumping ahead a bit, but I'm trying to decide weather to sew my sail, or order it from Duckworks, who have a 6 to 8 week lead time. Anyway, I think I can do it myself with some additional info. MIK, do you have any more detailed info or plans for the sail? I am handy with a sewing machine, but am not familiar with the details and some of the terminology of sailmaking. Also, has anyone out there tried their hand at sailmaking?

Thanks,
J

m2c1Iw
25th May 2008, 11:03 AM
Hi J,
Surprised nobody has responded to your question. I'm about to make a lug sail for my PDR from polytarp using Miks directions, have a look in the PDR thread for some info.

However the GIS in my opinion deserves a professionaly made sail from good quality material for best performance.

Good luck
Mike

bitingmidge
25th May 2008, 12:01 PM
I'm sorry I thought this question had been answered by Mik!

Perhaps it was your question Mike? I agree with your answer though!

cheers,

P
:D

Boatmik
25th May 2008, 07:40 PM
Thanks for stepping in Guys. I received an email request for the same info at the same time (as often happens) and I thought it was the same chap.

Soooorry Tomahawk if I snubbed you. Unintended.

m2c1Iw gives the perfect answer.

The main reason for going for a better sail are the possible loads that the polytarp might have to deal with.

The power a boat develops is in proportion to its stability. The PDR has a 4ft beam and one crew. The boat has five and a bit with possibly up to three crew leaning out. Which is why the GIS mast has to be so thick for example.

this will put a lot of load on the sail too. I'm just worried that there will be problems even with the better grade of polytarp that can be sourced. There are signs of distortion on the thinner polytarp for the PDR - it is not critical - but you can see it. So I am nervous about using polytarp sails on the GIS.

I wouldn't. But maybe you would.

MIK

b.o.a.t.
25th May 2008, 10:06 PM
I don't think Tomahawk is asking about polytarp - I think he's asking for info/help DIY in proper sailcloth. About which, I know nuffink.
cheers
AJ

Tomahawk J
26th May 2008, 10:22 AM
Thanks guys, for your input. No worries MIK, I didn't take offense. Right now I'm leaning toward buying my sail from Duckworks, here in the USA. I think I could make one alright, but would probably do a better job after I've had some sailing experience. Maybe my second boat...

One question I have regards reef points. How many rows of reef points (if any) do I need for my GIS?

Thanks,
J

Boatmik
26th May 2008, 02:17 PM
I had the big reefing eyelets put into my Beth sails. They were really useful.

I have never bothered tying in the reef between though - the lacing or the reef points are pretty unnecessary. So keep that cost out of your sail if you like - your option.

The plans have two reefs marked on the sailplan. I would recommend both. The first is probably a good point for singlehanding in windier conditions. And the deep reef is a dramatic reduction to make it possible to get home under adverse conditions.

Michael

CCBB
27th May 2008, 11:00 AM
Sailrite in the US does very nice kits...you'd send in the sail plan, they cut the pieces and send back a kit...I made a lug for my dinghy and it went together beautifully.

www.sailrite.com

If you persue this, let us know how it goes.

Cheers,
CLint

Boatmik
27th May 2008, 11:57 AM
Howdy Clint.
I had forgotten completely about Sailrite. They have been around for a million years! I am inclined to be very favourably disposed toward this suggestion!

Here is their sail kit page incase you cannot find it on a most comprehensive site.
http://www.sailrite.com/Categories/popular-sail-kits

Not quite as cheap as I would have thought - but the quality and instructions will make up for it.

Price to get to Australia for a dinghy type sail would be around US$85.

Best wishes
Michael.

m2c1Iw
27th May 2008, 12:27 PM
Well I'll be, it never ceases to amaze me how the internet has changed retailing. I would never of thought there would be an online sail kit company out there. You mericans sure have lots of interesting suppliers and courtesy of UPS and google so do we:).

Mik I notice they already list specs for a GIS, perhaps you should get your name on the designers list, cool.

Mike

CCBB
27th May 2008, 09:19 PM
The "sail quoting" page where you can customize the kit includes options like # of reef points, cloth weight, etc. They do not give batten pockets as an option...I wonder if people have been ordering w/o the battens. Maybe Michael can weigh in on the cloth weight...they give 5.4oz as the standard. We do want batten pockets, right? Also, how much reinforcement in the luff...they give an option for a boltrope...the lug I used cruising one summer had this and allowed for excellent tension in the luff.

I sewed a Shellback Dinghy kit together from their kit and got it done in 1 day of sewing on a good machine with help from friends. I imagine this sail can be done within two days of work. It is fun work when you get the help, however the instructions and kit are very, very well organized from Sailrite.

The sail will still be close to $350 US and that is without battens pockets which I think may add quite a bit (reef points add $20) Duckworks offers the sail for $488 US in 3.8 oz cloth. Sailrite does have a 4oz cloth you can choose too.

Cheers,
Clint

Boatmik
27th May 2008, 09:32 PM
The battens are useful for depowering the sail during a cruise. They also make "power on" and "power off" more gradual. The unbattened sail starts pulling real quick - which can be a good thing.

If I was racing - I wouldn't use battens. Same if just a daytrip with people comfortable with sailing.

But if I was taking Great Aunt Millie out or was going out for a few days - a cruise begorrah, with gear aboard and so on ... yep - battens.

MIK

bitingmidge
27th May 2008, 09:57 PM
The battens are useful for depowering the sail during a cruise. They also make "power on" and "power off" more gradual. The unbattened sail starts pulling real quick - which can be a good thing.


I guess I come from a different culture entirely. If I were racing I'd definitely use battens... but they'd probably cost as much as the rest of the boat! ;)

Cheers,

P
:D:D

Boatmik
27th May 2008, 10:30 PM
That was my thought too Midge. Until I broke one on BETH - so I took them out and BANG!!!

Off like a scalded cat. A large part of the reason is that your battens extend the leach and make the sail more powerful when they can't extend the leach any more.

But the Lug rig battens only flatten out that middle part of the sail because there is no mast to restrict them from pushing the draft out of the sail.

Originally they were put in because the 1870s sailing canoes I had seen pictures of used them to control the sail and slab reef. They are not strictly needed for either.

MIK

bitingmidge
27th May 2008, 10:53 PM
But the Lug rig battens only flatten out that middle part of the sail because there is no mast to restrict them from pushing the draft out of the sail.

While I'm not arguing with your experiences, wouldn't that be a matter of getting the taper right? In this case they'd be thinnest and most flexible at the point of maximum camber, quite the opposite to what we are used to when a mast is involved.

With composite battens you should be able to dial in a camber across the sail, just as you can with a bendy mast. I'm not going to try it, and if we continue this discussion it'll end up like one of those boring threads on other forums where people who know a bit try to convince everyone they know a lot! (that's what I'm doing now! :D)


P

Boatmik
27th May 2008, 11:58 PM
I'm not arguing either you B@@@@rd!!!

You are so competitive on the non-competitive stakes - I have one friend who whenever someone tries to give him some advice he doesn't want ... he asks them "what are you so upset about". After a few rounds of this most of us are ready to throttle the B@@@@rd!

I think the basic problem is getting the battens to bend enough as there is a floppy edge at either end - so the cloth is very inclined just to push out further ahead at the front and rear end because the edges are straight and have little resistance to being pushed a little bit before they resist.. and it doesn't take much to flatten a sail quite a lot.

Maybe you can get a performance advantage using the right battens - but without doing a careful process the boat is much faster without any battens compared to the "wrong ones".

Best wishes
MIK

bitingmidge
28th May 2008, 12:11 AM
Maybe you can get a performance advantage using the right battens - but without doing a careful process the boat is much faster without any battens compared to the "wrong ones".

See, I told you it'd end up like one of those other forums! :D

Please everyone read the above quote and ignore the last two posts!

Cheers,

P
:D:D

Daddles
28th May 2008, 10:34 AM
where people who know a bit try to convince everyone they know a lot! (that's what I'm doing now! :D)

It's okay Midge, I wasn't fooled for second :rolleyes:

You don't want battens in your sails, they're just something else to lose.

Richard

bitingmidge
28th May 2008, 10:54 AM
It's okay Midge, I wasn't fooled for second :rolleyes:

You don't want battens in your sails, they're just something else to lose.

Richard

And break.

I made some beauties once out of WRC, stiffened with strands of carbon, and tuned perfectly. Fantastic things they were. Perfect sail shape upwind and off the breeze. I can't remember how many of them but it was a 40' mast and about and 11' foot and a fully battened big roached main, so you can imagine. About half a cubic metre of timber I suppose when I think about it.

Then on a downhill leg, I let the sail out against the shrouds, one snapped, then the next one, then all of them.

Then the sail was a funny shape with all these hard bits in it, and when we went about it flogged and broke all the battens into bits small enough to fit in the glovebox in the car.

Did I imply in one of the posts above that I like battens?

My mistake.

P
:rolleyes:

Daddles
28th May 2008, 10:58 AM
Speaking of sails Peter, how's the wing (shoulder) coming on?

Richard

Tomahawk J
29th May 2008, 01:03 PM
I just checked Sailrite's website, and they offer a kit for the GIS sail. Looks like a very attractive option. Which sailcloth should I go with, 5.4oz or 4oz dacron?

Thanks,
J

Boatmik
29th May 2008, 03:54 PM
Howdy J,

About 4.5oz would be perfect. Which is probably the dilemma that sailrite faced.

The lighter sail will last a little bit long but be softer to handle probably.

The heavier sail will last longer.

But there is not a lot in it.

Both will last well because the loads on the sail are well distributed with few high point loads - and the loads themselves are quite low compared to modern race boats.

Best wishes

CCBB
30th May 2008, 01:51 PM
Lets see if Sailrite will do a 4.5oz kit. I'll look into this at some point.

However, I can use some more understanding of battens vs. none. I had a 30 footer with a full battened main and I very much like the way it kept the flogging down and maintained the sail shape nicely...would this be so for the lug, too? I don't see why it would be better for cruising vs racey kind of sailing. The only other criteria, besides cost (no battens would be cheaper and simpler), is would the un-battened sail stow more tidily in the boat?

So, if I understand it right, the suggestion is if cruising and playing for fun, battens are good, if racing and going for fast, no battens? What is the rationale, seems a bit counterintuitive.

Thanks
Clint

Boatmik
2nd June 2008, 10:25 AM
The weight is not critical. In a raceboat it might be - a tiny performance difference - but that would make a racing sailor a bit worried all the time.

With the Goat, I don't think there will be any problems with the heavier cloth.

Or that is the way I would prefer to go if there is no in between option.

MIK

CCBB
3rd June 2008, 08:36 PM
And the battens...are you saying they add weight but make the sail more manageable...still unsure of pros/coms. I'll get a quote from Sailrite for adding batten pockets.

Clint

Boatmik
3rd June 2008, 10:57 PM
And don't forget to check the price compared to the Duckworks $430 GIS sail.

MIK

arbordg
5th July 2008, 12:51 PM
We've been quite happy with the GIS sail we got from Duckworks