What to do about Royalex cold cracks and surprise staples?

Advice
#1

This is my first public post on Paddling.com; already learned so much reading others! Love this site already.

My question is about unexpected staples (to me as a novice at repairing ABS boats) under the gunwales of my canoe that pin the hull to the inwale. Can/should I take them out to repair cold cracks and if so, how?

Here’s the story: I bought this 1998 OT Penobscot 16 RX a few days ago (for $300); it’s got 5 cold cracks (5, 6, 7, 10, and 15 inches long) It’s got nice wooden gunwales and–other than the cold cracks and some dry wood–is in great, nearly unused condition. I reached out to @anon64780766 because I’d seen on other posts he had a lot of experience on fixing cold cracks (and much more!). His advice was great, so I thought I should move this whole thread into the public forum so others can benefit /contribute to this exchange. Here’s what I wrote:

…I’m planning to repair them with G-Flex and (maybe) some 2inch glass tape I got at West Marine. My question: can I do this without removing the wooden gunnels? The wood is decent shape and I’ve never taken apart a boat before so I’m nervous about that and trying to do as little labor as needed to get this thing seaworthy! I was think that I could use a dremel bit (#194) to widen and bevel the cracks, fill/sand with G-flex on both sides (putting glass on the inside only) and then fill the cold cracks from above with a syringe without removing the gunnels. Is this a bad idea? And advice much appreciated!

Here’s what @anon64780766 suggested:

It sounds as if you are on the right track. I have repaired cold cracks using G Flex thickened a bit with silica powder without backing the repair up with a patch and they have held up fine. But I might be inclined to use a patch on the hull interior for the long crack.

You might find that partially removing the gunwales is not as hard as you think. If the wood is in good shape, the screws might back out easily. The screws that are most likely to give trouble are long screws at the stems that enter from the outwale side and secure inlaid deck plates. If you have on-laid deck plates removal is much easier.

Sometimes a stubborn screw can be loosened by heating the head of the screw with the tip of a soldering iron. If you can loosen up enough screws to be able to just lift the gunwales clear of the hull about an inch, you will be able to get to the top of your cracks.

If you can’t loosen the gunwale screws or don’t want to you can still repair the cracks. In that event I would start by guttering out the cracks on both inside and outside as high up and close to the gunwales as you can get. You might need to widen the cracks a little to insure good epoxy penetration to the depth of the crack. You can drill a series of adjacent holes in the crack wide enough and over a long enough stretch to introduce a bare hacksaw blade into the crack and then run it up and down.

Guttering out the cracks is important as it greatly increases the surface area for epoxy bonding. If the gunwales are still in place, turn the canoe bottom side up and try to get some epoxy into the portion of the crack that is covered by the inwales and outwales. A ‘dental syringe’ with a long, drawn out tip can be very useful for this purpose. But be aware that the epoxy is going to ‘glue’ a short portion of the gunwales to the hull which will make them more difficult to remove later should you need to do so.

Although I use thickened G Flex to fill cracks I would use unthickened resin to bond cloth to the hull.

So this morning I unscrewed the metal (brass? copper?) deck plate off of the bow end and began to unscrew the brass screws connecting the outwales to the RX. First surprise was that at least two of the screws were broken (meaning that part of them is left behind in the inwale. Argh! How to get that broken piece out w/o trashing the wood?) The second surprise to me was that (as far as I can see so far, having removed four screws) the whole boat appears to be stapled to the inwale. The staples (or whatever this hardware is called) is, of course, rusty, and solidly embedded in the vinyl. Is this normal? It looks like it was factory done. And should I even try to remove the inwale? if yes, how? I’m thinking I might just loosen the outwales at each end, leave the inwales alone, and try to fix the cracks that way. But it sure would be nice to remove all the wood to make it easier to fix the cracks and so I can refinish them. Advice welcome! Here are photos of what I’m up to:

[15 new items added to shared album] 1998 Old Town Penobscot 16 RX
#2

Couple of comments; hopefully pblanc will verify.

You could orobably drill out the broken piece of brass screw with a steel bit and then use the next larger size screw. Or you could reattach the brass end caps with adhesive. Or leave them off since they aren’t essential. Or ignore the broken screws and reattach with the remaining screws; you don’t need all 4 screws to hold those end caps in place.

Regarding the cold cracks was it mentioned that you need to first drill a hole at the tip of each crack to stop them from growing? The stress concentration is at the tip.

Just FYI I’d oil the cane on those seats immediately or they will surely tear the first time you sit on them. The cane looks pretty bad so you may want to just plan to recane them.

Hopefully pblanc can answer your other questions.

You have a nice project. I had a Penobscot 16 and I think they’re great canoes.

#3

thanks, @TomL, this is helpful. Yes, I’m super-excited to have the Penobscot 16. My friends have one and it’s a really good multi-purpose boat, they say. It will certainly be a lot tougher and lighter than our old wood canvas!

I’ll give the steel bit a try to get out the broken screws. They’re in the gunwales (not the end caps) and so the next size should work find.

Good tip on drilling out the end of the crack. will.

and yes, want to take all the wood off if I can to refinish–and oiling the cane asap! Might even replace with webbing. Really appreciate the support!

#4

I know of canoe makers who epoxied the gunwales to their boats. I have not seen inwales stapled to the boat, but there’s always something new under the sun.

But I am thinking that boat was rerailed somewhere along the way. The vast majority of Penobscot 16s had black vinyl rails although I do believe that wood as an available option. But the great majority of makers drilled the holes for screws for wood gunwales from the inboard side, except at the stems where there was insufficient room to insert screws from the interior.

For the purpose of repairing the cold cracks I don’t think it would be necessary to remove the inwales. For the one inch of the cracks that lay under the outwales you could simply gutter out the crack deeper from the exterior side over that short distance. The inwale will support the crack repairs at the sheer line so an interior patch can end at the bottom of the inwale and strength will not be compromised.

As for removing the shaft of a broken screw, yes I would try drilling it out. Put it can be a real pain as the drill bit will want to ride off the metal and into the adjacent wood. See if you can indent the very center of the broken shaft with a very small punch or even a steel nail first. Then start with a very small drill bit and go up in sizes by increments trying to keep the hole centered on the broken shaft.

1 Like
#5

many thanks, @anon64780766; I’ll leave the inwales in place and just repair the top inch from the outside. The outwales are all screwed on from the outside, so, based on what you’re saying, the staples and these screws make the case for this being a rerail, not a factory job.

I’ll give it a try on the punch and then drill, praying that I don’t stray into the wood!

It is weird that the whole inwale is stapled onto the hull under the outwales. And the staples seem to be the point at which the cold cracks begin…

I’ll let you know how this project unfolds.

#6

I can’t remember the last time I saw an Old Town Canoe, that was not a wood and canvas model, that had factory-installed wood gunwales. I know that they do exist but it is hard to even find photos of them on the internet.

Most all makers who installed wood gunwales at the factory made it a standard practice to insert the gunwale screws through the inwales rather than the outwales. It is possible that Old Town was an exception to this rule but as I say, I can’t recall from memory.

It is not uncommon for those rerailing canoes to drill all the holes for gunwale screws through the outwales, however.