Guide to Strip planking construction?

RW, I think RED is referring to post #31. Here, I 'll quote the relevant para for you -

- seems a sensible idea, several kayak and canoe builders I talk with use it. Wish I'd thought of it when I was doing my stripper . . .

 

R Watson,
When the planks start to get to much twist you lay a long plank over the top to get a new fair line and cut with a circular saw set to depth, then just continue planking. Bevelled planks are really only required on flattish sections, where you have enough curve (convex) square planks are fine. It is always prudent to go inside and clean any seepage whatever method but there is far less when the planks butt on the inside radius. And certainly not enough to warrant an extra man. Making the glue stiff so it doesn't run through is a bit iffy I would think as the wood is going to steal further resin from the mix.
I was employed as the glassie to build the decks from a mould but I helped with the first three cedar strip hulls one of which became the hull mould plug. The main guys were a pair of Kiwis bought over to do the job, this was post Americas cup defence in Perth ('87) and was my second job here about '89-'90. The boats were Farr 9.2s we went on to build all plastic boats with interior liners etc, not sure how many where built but they are still a solid class here and run a state and national championship.
The hulls started as cedar then went to foam sandwich and finally to core mat which I had no part in.
I even built an all vinyl ester (Derakane) and foam boat to super light specs and post cured for the principle to race with.
On the second hand market the cedar and foam sandwich hulls fetch the premium prices. The cedar because the interiors where a ply and teak fit out pre liner, the foam sandwich because they are light and stiff for racing.
Cheers,
RR

 

A concern I would have with beveled and/or butted plank edges on the inside of the hull would be whether or not the bog was properly and fully forced into the gap. I think that a gap on the inside of the hull is critical to insuring a 100% bond between strips. I plan to use a similar method, but use a structural filler between planks. I plan to use a fairly wet mix as some preliminary testing has shown that the epoxy wicks into the planks a fair amount. Seams that were smooth to begin with were concaved by the time all was cured. Close attention will need to be paid to get consistent flow qualities that will also resist slumping one in place.

It may also be advantageous to lay a series of planks and bog them while there is still open access to the inside and the outside of the hull, especially if you are working single-handedly. I plan to bog in sections to keep the mess contained to small areas at any given time.

 

LP.
As I have already mentioned, the fact that the planks do touch allows a wetter mix that will indeed flow and wick in.
Further, part of your prep prior to glassing the inside will be to sand with a large disc sander to knock off any edges, this will expose any further voids. I guess any method is only as good as the tradesman. We used rubber squeegees to apply the bog which worked extremely well.
I have described the method simply to put it out there that gluing on one plank at a time is tedious and slow and gives strip planking a bad rep which it doesn't deserve. This method is also really only applicable where the timber is a core, these days you can go even lighter with Paulownia.
Be really careful with this structural filler idea it will be a disaster if it doesn't sand at the same rate as the timber, whilst the timber does give some directional strength it is still essentially a core so the glue need be no stronger than the timber. Would you use cotton fibre to glue foam ?
If the timber is most of the strength and lightly sheathed I probably would cove and bead, or use another method altogether.
LP if your timber is a core only and you use a wet structural glue, getting it fair with hard glue lines will be a nightmare of huge proportions. Good luck with it.
Oh PS. Any concave in the glue line will sand out when you fair surely.

 

Thanks for your input redreuben.

Agree whole heartedly.

I'm still relying on the strips to provide structural support. The hull will be bright above the waterline and so heavy laminate schedules won't be allowed there. When I say "structural", I am matching the bonding agent to the surrounding structure. In this case, the cedar planking of the hull.

No, but I might add some to glass bubbles to create a specific physical property.

Bead and cove...Ugh. It's fine for some applications, but I'm fine with squared planks and my intended method.

No disagreement hear. That's the great thing about epoxy and all of the modifiers you can use with it. You can build the bonding agent that is suitable for specific tasks. Structural fillers can be combined weaker/softer fillers to get the strength and hardness that you desire or need.

No worries here. I only mentioned it to validate my statement about epoxy being wicked in to the hull planking. Also to emphasize the need for a wet mixture to be used so that dry joints are avoided.