wooden gunwale replacement

[The Good Goose]

The gunwale on my dyer dinghy was shattered along with the bow of my dinghy in a windstorm. I have fixed the fiberglass and am attempting to fix the wooden gunwale. The original was 1/2" by 1 1/8" white oak on each side of the fiberglass riveted together. My plan was to rip thin strips and epoxy them together to replicate this size. Unfortunately even using 1/16" thick pieces I could not make them bend up the sheer and around the front of the bow.

My new plan is to steam the pieces. I was thinking of using 2" pvc pipe for a steam box. My questions are as follows

1. will 2" pvc work for a steam box?

2. the white oak I have is kiln dried. will I need to soak it before steaming ? if so how long? will kiln dried work?

3. How long will I need to steam the pieces 1/2" BY 1 1/8" BY 12' LONG

4. can the piece just rest on the pipe or should I put some screws through the center axis of the pipe and let the piece rest on them?

5. I plan to put the inlet on one end of the pipe and drill a hole in a cap on the other end . What size outlet hole should I drill?

6. Should the steam box be level or oriented so the outlet is higher or lower then the inlet?

I have never steamed anything before so any advice or tips would be greatly appreciated.

Brock Richardson

[Hirilondë]

Before I reply to the questions let me add my name to the list of nomenclature fanatics. ;>)

The piece, either single or laminated along the outside is a gunwale also spelled gunnel and the one on the inside is an inwale.

1. Yes, anything that will hold the piece(s) and be relatively well sealed and not fall apart under steamy conditions will work.

2. Yes, definitely, and even then you may find that it breaks. Over night will do all that soaking can do. Green is better, but if you don't mind the chance of ruining some pieces kiln dried can be bent.

3. An hour per inch is the general rule, so 30 minutes.

4. You can probably get away without the rests.

5. This depends on how much steam pressure your heating source generates. Probable a 1/2" dia. is good. Keep an eye on things, if your tube starts to whistle loudly through the hole turn the heat down.

6. Outlet should be slightly lower. This will drain the condensed steam out before it cools your wood. You are steaming, not soaking.

Misc thoughts:

Make some sort of a mold of the curve around your bow but reduce the radius by about 10%. You can do this by mounting blocks to a piece of plywood that you have drawn the curve on. Clamp your steamed piece to the mold and allow it to dry completely, will take at least a day and waiting 2 won't hurt any. When you remove the clamps the piece will spring back slightly, that is why you want to "over-curve" it.

Have your mold, clamps, gloves (steamed wood is very hot) and a helper is good too ready before you start. You have but a minute or two from when you remove the piece from you steam box until it cools to the point it won't bend easily. Rehearse the procedure by placing the wood on the mold and practicing tightening clamps ( you won't actually be bending it during the practice). Nothing about this is overly difficult, but fumbling with the process while your wood is cooling doesn't help you get it clamped in time.

Best of luck to you.

[The Good Goose]

Thanks Dave
That was exactly what I was looking for. I had never heard of an inwale before so it was good to learn that as well.

Brock

[Tim]

gunwale also spelled gunnel

This apparently seems to be true, but real sailors spell it "gunwale". ;<)

4. can the piece just rest on the pipe or should I put some screws through the center axis of the pipe and let the piece rest on them?

Be careful using any metal in your steambox. It will get extremely hot during use, and common screws might stain your wood. Dowels are better.

You probably don't need the rests for this job, but if you want your steambox to be on hand for some unknown future use, it makes sense to built it with versatility in mind. Given this, you might choose a larger diameter PVC for the steambox.

[Figment]

I love that we all do things and speak of things in slightly different ways. Boats would be so dry otherwise.

In the canoe world, where there in an "inwale" there is also an "outwale" which together make up the "gunwale".

I use a 4" pvc pipe for my steambox. 2" is too small, you'll need chopsticks to reach in and grab the hot wood. Yes, I just let the piece rest in the pipe, but I flip it every ten minutes or so.

Your steam box whistles? I didn't think the object was to create that kind of pressure, but to promote circulation of the steam. Horses for courses.

I've always oriented the box with the outlet high, so that condensate returns to the steam chamber (a $12 electric hotpot, in my case)

A pro-woodworker friend of mine recently redid a Dyer, and he had one heck of a time bending around the bow, even with steam, but I think he may have been trying to make it happen with a solid piece instead of with laminations. Either way, I mention it because he had to resort to a compression strap to finally make it happen.

[Hirilondë]

Your steam box whistles? I didn't think the object was to create that kind of pressure, but to promote circulation of the steam. Horses for courses.

No, and that is why I suggested he turn the heat down if his does.