re-building a cedarstrip duck/ hunting boat, question and design

[fredygump]

Hey everybody, awhile back I posted with photos of an old duck boat I found. Now I'm well into the project, and have a few pressing questions. This isn't a "restoration", because I'm remaking it as a wood epoxy boat. My apologies to the purists, but it was never a good boat. And since it was a homemade boat, my conscience is clear. (If it had any historic significance, I would have much more respect for it.)

First of all, the boat is a cedar strip, edge nailed, and it's modern enough that the builder used an orbital sander. It's clearly a home built design, and it was never a good boat. The edge nailing of the strips split several of them down the middle, and it based on the paint in the cracks, I believe these strips split while the boat was being built... I think that explains why it was in fairly good condition.

I'll get some photos up, but the immediate questions are about material for ribs and inside stem. The ribs where white oak, and they dry rotted. I'm replacing them, but more for aesthetics than for structural integrity, since I'm planning on glassing this boat inside and out. I'd like a light colored wood that contrasts with the old red cedar strips. I've thought of ash, or white birth; I don't have any experience replacing ribs, so any thoughts will be appreciated.

Second question--the inside stem. Originally it was white oak, and it cracked; is it going to matter what I use to replace it? Bending a piece like this is new territory for me, because in the past I've only steamed strips of cedar for stems, and that was several thin strips glued together. This will be a much bigger piece of wood, so I'll need to build a "real" steam box...


I'm attaching a photo of the boat as I found it. Hopefully that will help explain what's going on here.

 

[Dave Wermuth]

Hi, you could laminate stems for this too. YOu're familiar with that process. Steam bendiing articles can be found here and on youtube, it's not all that hard but it can be frustrating. Boiling is an alternative to steaming and might work for you. Oak is a good wood to use. So is Ash, or chestnut. I don't think birch bends well, i'd not try it. Stems and ribs all the same wood. the problems with 'glass: it's going to split open at the keel and it makes the boat heavy. Too bad the boards split. I'd pre-drill everything. There is a product called CPES that is a clear penetrating epoxy sealer. You might want to consider using it on the wood once it's all stripped. It is an epoxy but it might be appropriate for this boat.

 

[fredygump]

Do you expect fiberglass to crack along the keel even with ribs and half ribs in place? Granted I've removed them for the moment, but they'll all be replaced. I don't expect there to be much flex alone the keel, but I haven't done this before...


And for weight, it's already heavy enough that I expect to haul it around on a trailer. So a little more weight doesn't seem all that bad.

 

[Dave Wermuth]

I do think it'll split there. They all seem to. the wood is organic and will move, swell, shrink, the glass won't, it'll split. think of the sidewalk beside the tree. So, I think a reinforcing strip of glass along the keel could be a good thing. A layer under the main piece? If it's reinforced maybe it won't split.

 

[Dave Wermuth]

Question: the ribs and half ribs are out of it? Will you be glassing the inside just like the outside with the ribs and half ribs out? And then replacing the ribs/half ribs? that might negate all my keel splitting forecasts.

 

[fredygump]

Question: the ribs and half ribs are out of it? Will you be glassing the inside just like the outside with the ribs and half ribs out? And then replacing the ribs/half ribs? that might negate all my keel splitting forecasts.

That's the plan. Glassing over the inside of the boat with the ribs in place sounds like a nightmare, and a bad idea. It hurts to think about how many bubbles would form in the fiberglass cloth when working around the ribs....

But yeah, ribs were removed to help stripping. The boat is edge nailed, which helps hold the strips, even without the ribs, but I also applied a thin coat of epoxy to help hold everything together. I removed ribs in sections, stripped the section, sanded it, and applied the epoxy, which I "thinned" with alcohol.

So now I'm planning on glassing the inside without the ribs, and then install the ribs.

I'll use a light weight cloth on the inside, maybe 4 oz. I'll probably lay a thin strip over the keel on the inside like you mention, for a little security. Then I'll install the ribs, trying to replicate the original construction technique.

I can't decide if I should varnish the ribs once they're installed, or if I should glass over them individually after they're installed. Glassing them would make everything stiffer, but clear fiberglass shows dings pretty readily, which would make the boat seem more fragile than it really is.

Anyway, I'll throw some photos up as I go along.

 

[fredygump]

A layer under the main piece? If it's reinforced maybe it won't split.

Is putting the layer underneath right? I personally had a bad experience trying it in that order. I don't know if it was because I was using light weight cloth (3.7 oz s-glass), but the overlap was really obvious. I sanded as much as I dared, but I would have had to sand most of the way through the top layer to feather down the edge created by the double layer.

So with that in mind, I'd put the second piece on top, so I can feather out the edge without cutting into the main layer of fiberglass.

 

[Treewater]

it was never a good boat. and it was never a good boat.
May we pause momentarily for the injury to this boats feelings?

 

[fredygump]

it was never a good boat. and it was never a good boat.

May we pause momentarily for the injury to this boats feelings?

Yes, sorry. I will have a heart to heart chat with my boat as I struggle to mend the split planking. It was quite a nice boat, if you overlook the broken and leaky bits.

 

[Steve Ambrose]

Consider G-Flex epoxy by West Systems. It's expensive stuff but allows for much more movement in the wood. I use their thick product to repair old stems that have too many holes to hold tacks. It doesn't split or chip when you drive nails or tacks into it. I've never used their regular epoxy but I have messed with a board that was coated in it and it took nails without any cracks or splits.