Noob Stitch and Tape Canoe question

[CaptainSillyboxes]

Hi everyone

I'm in the middle of building a stitch and tape canoe, first project like this I've undertaken. It has 4 chines so all the angles are very obtuse.

The instructions give two options for the seams: tape both sides, or only tape the inside and fillet the outside.

Seems to me that the latter option would give a nicer looking finish and would be lighter and cheaper and quicker to build. But all that counts for nothing if a seam fails!

Does anyone have an opinion as to the wisdom or not of only taping the inside?

[Oldad]

I think the very essence of this method of building is taping both sides,

[wizbang 13]

I build my wee speedboats with no tape. Big 403 filets only.
Well, okay, I used a few feet up forward on the inside, where the angle is "obtuse".
This boat bangs around in an hour more than a canoe will in ten years...


I think taping both sides of a kayak,canoe,8 foot pram is daft.

It's not until a small boat falls off the back of a pickup at 35 mph do we see how overbuilt a smallboat is.

[Oldad]

Dang! I knew this would happen. I almost added in my post that Bruce would have a different opinion, but held back,
I believe Bruce uses large fillets, whereas I prefer smaller fillets and tape. My guess is it uses about the same amount
of material, adds about the same amount of weight.
As an aside, I have used nothing but thickened epoxy on above deck work, no tape, no fillet, and have had no failure, so....

[CaptainSillyboxes]

What I might do is, try it both ways with some little scraps and see how much difference there is, and how tough generally the singly taped one is

I would tape the stems both sides in any case.

That speedboat looks ace

[CaptainSillyboxes]

Re large fillets, the reason I mentioned obtuse angles is that as the seams approach 180° there's less and less for the fillet to actually hold on to, as the epoxy is just sitting on the surface. So where the panels converge onto a single plane as they do in the bow, stern and midships the tape will really be doing all the work

[Oldad]

You will be surprised at how strong the joint is without tape especially if you have a bit of a gap at the joint so the epoxy can saturate and connect with all of the plus. You will literally destroy the plywood on either side of the joint before the joint will fail (if you do it right). Me, I am a belt and suspenders kind of guy.

[wizbang 13]

yes yes, of course glass both sides when yer approaching 180
even a buck n a quart

[CaptainSillyboxes]

Thanks for all the previous comments. I have another question. What's the best way to achieve a fair surface after applying fibreglass tape? Sanding the edges of the tape or building up the adjacent surface with slightly thickened epoxy or some other filler?

[Woxbox]

Thanks for all the previous comments. I have another question. What's the best way to achieve a fair surface after applying fibreglass tape? Sanding the edges of the tape or building up the adjacent surface with slightly thickened epoxy or some other filler?

I like a bit of both - reduce the size of the edge and then add the fairing compound.

[John Meachen]

Thanks for all the previous comments. I have another question. What's the best way to achieve a fair surface after applying fibreglass tape? Sanding the edges of the tape or building up the adjacent surface with slightly thickened epoxy or some other filler?

Every few weeks I find myself posting the recommendation to shave off a sliver about 1 1/2" wide and 1/32" deep on the outer edge before glassing so that the tape can easily be faired and the panels retain the intended surface.The alternative is a lot of filling and sanding.

[CaptainSillyboxes]

Ha, that's a great idea but too late for me to do that now!

[CaptainSillyboxes]

I have another question. A local sawmill are providing me with some douglas fir sections for various parts of my canoe, but the only pieces they have that are long enough to form the inwales and outwales are green.

Their advice is that I can use it green since douglas fir doesn't shrink much. For my part I can imagine it would make it easier to bend these pieces into the correct shape.

However, I don't want to wait for months for it to dry before using the canoe, I want to get it salty this summer!


So this question comes in two parts:

1) is it a reasonable idea to bend and epoxy green douglas fir into place for inwales and outwales or will shrinkage cause problems?

and 2) would I need to wait for it to dry out completely before varnishing?

thanks

[dbp1]

I'm not sure about using green wood, but you can always scarf your way to long pieces from shorter stuff.

[wizbang 13]

By "shrinking", I think the piece,once installed, may check or crack, not actually get smaller or contort the boat.

[willin woodworks]

How green? You can quickly season thin stock by steaming it in a long poly bag. Lots of info in the archives about steaming in a bag.

[CaptainSillyboxes]

I've ended up getting half lengths of seasoned material and am going to scarf it together. Thanks for the comments.

[sp_clark]

Ha, that's a great idea but too late for me to do that now!

That's why we're here after all; what you're getting in reply are hints for your next build!

[sp_clark]

I like a bit of both - reduce the size of the edge and then add the fairing compound.

One tip I picked up (maybe from a video over at Off Center Harbor?) was to pull some strands from the lengthwise threads in cloth, leaving the crosswise threads in place. Do that it reduces cloth and epoixy thickness over the area from where those threads had been pulled.

[CaptainSillyboxes]

Hi everyone, I'm back with another question - need to choose what paint to use for the outside of my canoe, which so far is coated in epoxy-based fairing compound or unthickened epoxy wherever the fairing compound isn't.

Someone recommended a cheap and cheerful product called Bedec multisurface paint

Someone else told me that suggestion number 1 is "a bit agricultural" (whatever that means) and I'd be better off using a marine grade alkyd paint.

Anyone have any other suggestions?

I want to avoid anything that requires one person to roll and another to tip off as I'm doing this on my own!

I'm planning to store it next to my house under a cover when it isn't in the water (ie most of the time)


thanks

[Woxbox]

The cheaper option I've had most success with is Rustoleum enamel paints. They have a pretty good color selection and it goes on and holds up well enough. Rustoleum does make a line of marine paints, too, but I've never seen that at a hardware store.