Thread: Redbird: a strip-built canoe ... the Journey

Originally Posted by bitingmidge

I suspect there's a lot of the old "here's one I prepared earlier" going on here!

Maybe. With Curlew I had pre-assembled all the parts several times before I committed to epoxy. In the end it was like assembling a kit.

Hard to do that when it's strip planked though!

A few replies first

Thanks for the input, I've mainly started this thread for folks out there who haven't done any boat building to get a feel of the trials, tribulations and decisions that have to be made ... material availability in Oz etc as the books don't tell you these sorts of things. But having input and encouragement from the experienced is fantastic. Thanks guys.

Originally Posted by onthebeachalone

What gets me is the way you take "the long way round" with meticulous detail work, and do it so quickly! You must be a really efficient worker who doesn't spend half the day in the groaning chair figuring out what to do next.

My interpretation to three days to the outwales and decks on, and to play a little bit with the paddles is not what I call quick!! As far as sitting around in the groaning chair ... when I'm out there I seem to have little time so i try to make all the decisions after dark ... when those things arise that I have to make a decision on the spot I do it without too much deliberation and because of that I pretty rapidly determine if it wasn't the best decision but there are always work arounds and I enjoy those challenges What I find is that if I wake up at night thinking about something I shouldn't (work for instance) I divert my thinking to the next stage of the canoe and mostly there are no surprises when I'm out working ... There was a huge surprise (read that disaster) today but I'm not up to reporting today as I'm a couple of days behind ... more on that later...

Originally Posted by jmk89

Ramps
BTW - I use vinegar for epoxy clean up (cheap as chips in big bottles from the super market, easy on your hands, doesn't dissolve rubber gloves and can also be used as a rust remover).
Cheers
Jeremy

Thanks Jeremy I'll try that again, I tried vinegar on the uncured epoxy that I got on my fore arms once and I think I was more successful in rubbing off the hair than the epoxy, but I'll try again.

Originally Posted by bitingmidge

I suspect there's a lot of the old "here's one I prepared earlier" going on here!

No comprende A pre-made gunnel or deck for a stripbuilt??

Day 36
(this is only last Sunday, I've almost caught up)

Most of a day at it …wow

Estimating launch date to be Australia day but haven’t started the varnishing yet.

Had a bit of play with the paddles and decided that that was a good thing to do after work so got stuck into the gunnels again. Cut about 60 plugs of pale Sheoak to cover the screws in the outwales (I quite like the idea of a contrasting colour) and glued them in … I just used water resistant PVA here as I figured they would be covered in varnish, they’re non structural and I can replace them pretty simply if one or two were to “fall out”. I got stuck into the shaping and sanding the gunnels again which took me most of the afternoon but I’m happy that they’re ready for varnish. …Next the thwart/yoke.

All right I may as well catch up
Day 37
A few hours after work

The thwart … or should I do a yoke? Yokes look nice. Don’t be silly how far am I going to carry a 6m canoe by myself … I could take up kite surfing I spose … with a wooden kite … a thwart it is then. Played around with the shape for a bit and size. Then I roughed it out with the lancelot (chainsaw version of arbortech … yeah scary … hmm… wish I had a bandsaw ... have I mentioned that before?) followed up with the mighty Triton random orbital sander attachment (a lot more aggressive than my DeWalt ROS)

... wish I had a camera , mines back from the Docs but still in Perth ... might have to see if I can borrow one for a day or so

Day 38 (That be yesterday)

Day 38
Few hours after work

Took another look at the thwart and decided it was about double the thickness it needed to be after I put it between two chairs and jumped up and down on it. Put it through the thicknesser a few times then cut it to length, wedged into its home (temporarily) and got stuck into mounting the seats. After much measuring, cutting and drilling little bits of wood I got the stern seat mounted … wow … I felt it was another milestone … really looks like a canoe with a seat in it … should I … is it all mounted securely … yeah let’s give it a go … I had to sit in it … wow … what a buzz . (what a laugh maybe it's good no one saw me sitting in it up on the supports ... but if they had a camera I would have posted it ... maybe )

Now to the bow seat. This going to be more difficult as I’ve decided to make it reversible … bit like the Green Valley sliding seats. I figure if it’s a symmetrical designed canoe I may as well make use of the “either direction” characteristic and put the seat as central as possible when I’m paddling myself and with “directional” shaped seats I had better make it reversible … thoughts and designing in progress.

Bu99er I need my camera , maybe some pics tomorrow

Day 39
Yes Today Wednesday the 17th Jan ... I've caught up!

Only 1 ½ hrs after work today and wow what a day.

Well I successfully destroyed more in 1 ½ hours than I have for the entire “journey”. I was measuring seat supports, went and found termites in my drying stack of Sheoak (no that wasn’t the issue as they are more interested in the bark and dodgy wood than the sound timber) found a couple of good looking outwale off cuts for the rails but was unsure about their strength. I brought them all inside and placed the rails on a couple of chairs at the distance that they would be supported placed the seat in between (tried to place it fairly central to into maximise stress on rails). Considered putting pillow underneath in case they weren’t strong enough but nahh, she’ll be right . Well I was right they were sound so I bounced a bit harder and the seat broke . My fault there was a knot in the middle of the back of this seat and I was worried more about how it looked knot (scuse the pun) its strength . Despite the setback I see the day as very beneficial as I would hate this to happen on launch day when my lovely wife sat on it… talk about embarrassing . So now I’m removing the cane to see what I can recover … would be a lot quicker than starting again (I think)

Originally Posted by Ramps

I bounced a bit harder and the seat broke

Oh! Maaaayte!
. What a disaster.
(BTW, have you ever thought of taking a leaf out of Daddles' book and becoming a writer? The drama and suspense in this story is amazing.)

Howdy All,

Not to be critical here, but to offer some thinking...

Over the years I've been involved in helping with other peoples' boatbuilding in different ways I've seen quite a few long discussions about the test breaking of bits of boat.

This can either be in practice or on a theoretical basis.

The worst case I ever saw was a fellow who was building a Bolger Micro.

As you probably know Bolger is one of the greats and seldom puts a foot wrong in terms of structural strength or performance in his designs - they simply behave how they are supposed to. There is an occasional glitch because he is experimental in approach, but generally minor and maybe affecting 10 or so of his 600 odd designs.

Anyway this Micro builder ran into a Mechanical Engineer who was interested in building a Micro too. The Engineer told my friend that the Micro would not be strong enough as designed and came up with a whole bunch of equations to show just how the Micro was not strong enough.

(And that's with over 500 of the blighters built)

At this stage my friend came to see me (I was working at Duck Flat at the time - we had sold him this batch of absolutely beautiful fine grain Oregon - about 30 rings per inch minimum - Beautiful stuff) and he started to explain how the boat wasn't strong enough.

It went on for hours - because at that stage I hadn't learned that when an owner has a fixed idea - you just leave them to it - perhaps I was too emotionally involved in that fine grain oregon.

Anyway - after a couple of hours I realised it was useless so told him (nicely) - good luck and get on with it.

Then the phone calls started...
That keel can't possibley stay on.
The decks are too thin
The cockpit is not strong enough to deal with being hit by a wave.

Now I have enough engineering to know that a lot of what he was talking about was poppycock - the engineer just didn't understand some aspect properly - so I tried to show the correct basis for the calculation.

Anyway it went on. For about three years with him building and rebuilding bits of boats with the "advice" of the engineer - who for some reason hadn't started building anything.

In the end I ran into the builder at a Wooden Boat Association event and he started to tell me how he had started to reinforce the inside of the bottom of the boat where the keel attaches - I think he had it up from the 9mm ply suggested by Bolger and up around the 50mm mark.

Thanks Mr Engineer.

Anyway it was all too much and I said (somewhat loudly)

"Look Angus, you can always hit something hard enough to break it"

He never spoke to me again.

And kept taking bits of boat apart and rebuilding them.

In general there is nothing wrong with this - one of my great mates is a bloke who spent decades taking apart and putting back together a 1970's wooden ocean racer - built around the same time as the boat that just won the Sydney to Hobart.

His process was joyful - he loved outsmarting the builder and turning his own better keelbolts on his lathe.

But with the Micro - the owner wasn't having fun at all - he was frustrated and angry that the Micro "was designed so badly".

He was building the Micro (a very simple mini keelboat) for 12 years with constant weekly effort.

Now the point of this story is that the "engineer" probably did all the calculations right (apart from a couple where he didn't understand the nature of the structure) but what he had done wrong was in his assumptions about the loads. He didn't understand how a light highly buoyant boat like a Micro is very unlikely to have a metre of water over the decks - or that wave impact is going to be much less because a little boat will MOVE with the load.

And in the end I hurt the builder where he was most vulnerable - at a basic level he was frightened that the boat would break. And I ended up naming his fear - which was possibly a bad thing on my part.

He didn't get the boat sailing before he got terminal cancer and had to stop boatbuilding (though in the last couple of years he dropped the Micro and fixed up an old Hobie for his grandkids - good project!!!)

Another place there was a big discussion of this type was on the American PDRacer Forum.

There was a HUGE discussion about the "thin" ply we were using for our Australian PDRs. Some of the American's were adamant that the 4mm ply wouldn't have enough puncture resistance even though we knew most plywood racing dinghies here were built of the stuff in the 60s and 70s including 18ft skiffs.

And one of the Americans worked out a neat method of testing using a screwdriver and some bathroom scales and found that 6mm ply was more puncture resistant than 4mm - and 9mm ply was more puncture resistant than the 6.

So some of the seppos were cooing and saying just how weak our boats would be.

Midge made the observation ...

"How many screwdrivers do you find strewn on the average beach?"

So anyway - not being critical of the body drop test of Ramps - but I have to ask the question - how likely is it to happen on a canoe - or does it qualify as an accident that would break something built the right size for lightness and adequate strength.

I'm not saying in the slightest that this experiment with the canoe seats is wrong - but just make sure the experiment is kept real and remember that if the plans and other similar plans have similar sizes for a part - then it is probably OK - even with some small defects.

Hit it hard enough and it WILL break at the defect - but the question you have to ask is whether it was the defect or the size of the applied load that made the seat break

Three things might make a huge difference.

1/ if the seat is not trimmed to the rather short length that it will be in the canoe yet, then the applied load will result in much greater bending stresses because of the longer length (Ramps took care of this in his experiment). Also when glued in place (if they are) the ends of the seats are restricted further in their movement (ie the Euler effect eg a shelf built into a wall at each end but with the same span as a shelf that is simply sitting on bricks will deflect much less because the wall will prevent the ends from changing their angle as the shelf deflects - whereas ends of the one sitting on bricks are free to bend to any angle they like).

2/ That the load from dropping your weight onto the seat might represent quite a serious fall for a person in an actual boat - and then it might be good for the bit to break and bring the person to a more gradual stop by breaking rather than hold up firmly and break ribs or arms.

3/ When fitted to a boat the supporting structure (the sides of the boat) are very springy so will deflect under large loads reducing the effect of the impact on the seat as energy is absorbed in the hull structure as well.

MIK

Thanks Mik

Read your article on the Eureka in the AABB the other day ... Good article.
Shame they got the author wrong on the table of contents

good discussion above

A lot of what you are talking about I had in mind although I can't for a minute assume that I know half of the stress dynamics of a boat as you do so my testing was just trying to be as realistic as possible.

If I was to build a dining room chair there is no way I'd build it that same and I am constantly reminding myself that there is a lot more give in a canoe, the canoe in the water, the flex of the hull etc etc but in this case I didn't bounce harder than I a I feel would have if they fell the last foot or so as the feet slip while attempting to plant the backside. Also the rails were on cushioned seats as I was trying to in partially imitate the cushioning effect of the boat int he water. The length of the "arms " on the seat are close to the final length. And no the seat isn't to be fastened in as such but will be clipped over the side rails, which should offer some extra "support"

As I was trying out the side rails, I wasn't expecting seat to crack

All the same thanks for the input lesson I'll keep in mind. I'm normally happy to build as per the specs of a plan it's only the design changes (due material or tool availability, or perhaps a different look) that I start testing. As I tend to over engineer things I'm trying to swing the other way and attempt realistic testing to comfort my worries.

Thanks guys

No probs Ramps,

A lot of thinking about boats should be the sortof stuff that occurs in the background.

To hear once and sorta file away for when it is needed - so glad you took it that way!

Cheers mate.

Day 40
About 2 hrs after work

Well I took some pics on my mobile phone, they’ll be cr@p but it was the best I could do on the spot … will download them tomorrow.

Chopped up the broken piece of the seat with a Japanese saw then took it to the router to see if I could surgically remove remaining wood off the tenons that remained in the seat. I surprised myself with the results. I dragged out the new upcut router bit set that I picked up a few weeks ago to cut a couple of mortises out of the new piece. It worked a charm and the glue is now drying.

This gave me half an hour or so on the one of the kid’s paddles. Anchored it between the dogs on the workbench and to it with planes and spokeshaves. The blade is all but there, into the handle another day.

the offending break
the cut up version of t he seat frame
the tenons after they have seen the router (sorry had trouble focusing the phone )
the new bit fits well

This is the smallest so I've deliberately tried to keep the surface area down. I'd prefer her continue putting the paddle in the water and doing a little bit rather than wear herself out in the first ten strokes.

Today I flipped the canoe back over. spent the the first hour and a half sanding and cleaning up, then put the first coat of varnish on ... looking good

This then gave me a bit of time for some domestics before getting stuck into the paddles again. kids paddles went like a charm but nearly two hours on each ... if I was into production some sort of router jig would definitely come into play but as they are all different sizes (and shapes) I didn't think it would be worth it. Besides it's pleasant (mostly) work with the planes and spoke shaves (this is where we need a dark-side icon ... and ideas)

Well still no camera so you might have to wait for the launch day to get some

Day 41

Another day of varnishing and paddle making today.

Started early and got 2 coats of varnish (nice warm 30 degree day for drying varnish) however I was considering a new name for it today … I thought Amber would be an apt name. Looking at all the bugs and stamens (Marri decided to start flowering, didn’t) in the varnish reminded me of all that jewellery I saw over in Europe . Oh well the joys of being one with nature … I suppose they’ll add to the UV protection. I gotta just keep reminding myself that the varnish is just there for protection, not to make it look pretty (yeah right well why don’t I just paint it then? )

While the varnish was drying I got stuck into the paddles. Another coat of varnish on the girls paddles and the two big paddles just need sanding.