new (old) canoe with repair Qs

Hello – I hope this is the right place to ask these quetsions. I purchased a 1987 Stillwater (White > Old Town) canoe in the 16’ length. It is in very good shape for its age, but is quite “flexy” in the center, yoke area. Upon inspection I noticed the wood carry handles and center yoke are wet/rotten on the edges against the hull and need to be replaced.

Question: I assume this will restore some of the rigidity to the boat? Do the vinyl gunwales affect the rigidity of the boat as well and need replacing?

I removed the handles and yoke with a screwdriver and 3/8 box wrench easily enough. I used to work on bicycles and have *some mechanical ability.

Any pointers or things I should watch for here? I think I found a site that sells the proper carry handles and new yoke. I just didn’t want to do anything stupid.

The hull is in very good shape on the inside, and outside is good too. There is one gouge along the keel that may need a fiberglass “fill” or something…so any pointers there are great too.

Thank you very much for your help!


Where is the flexiness occurring?
In the bottom of the hull? If so, a stiffer thwart is not going to cure the problem.

You don’t state the construction of the hull. Fiberglass? I had a '73 fiberglass boat that would pooch upward in the center if not loaded with gear. I solved the problem with braces from the thwarts down to the keelson.

Basic Stuff

– Last Updated: Mar-07-15 6:17 PM EST –

If the thwarts are so rotten at the ends that the bolts no longer make good contact with the wood, that would result in extra flexibility along the gunwales, but I'm not sure what sort of flexibility you are describing. The gunwales should still be stiff even if some bending can take place over long distances once the thwarts are removed (or not firmly attached due to rot). I'd be surprised if vinyl gunwales ever need replacing, but other folks here know more about this than I.

What is the hull made of? If you are finding that the bottom of the hull is flexible, that may actually be normal (though not ideal). Wide boats made of Royalex tend to have flexible bottoms, and polyethylene hulls are even worse. The only practical way to improve that situation is as described by EZ above.

Oh, the hull isn’t flexible - I just notice flexing if I push outward in the center on top of the gunwales. So it’s the “sides” that seem to be more flexy than I imagined they would be. I could hear a “ree – erree” sound when I sat in the stern seat and pushed my legs outward when sitting there.

Also, when cartopping the canoe on the way home I could get the gunwales to flex when tightening the belly rope around the hull.

Maybe most canoes do this to some degree – I’ll replace the center yoke regardless I think. Thanks –

Some flexing can be normal

– Last Updated: Mar-07-15 7:01 PM EST –

On my canoes that have vinyl gunwales, some flexing can be expected. For example, for a very short carry I might simply carry it on edge by one gunwale, even if the boat is lightly loaded with gear. The gunwale flexes a noticeable amount when doing that, but it would be much worse if the thwarts weren't there. That creaking sound that you hear could be thwart attachments or seat attachments. The seat attachments do almost nothing to stiffen the gunwales (unlike the thwarts), because the cross piece is well below the gunwale and therefore the various connections all can flex. The thwart attachments will probably be quiet if they are snug (which is less likely if the ends are rotten).

Okay – so I ordered a new 36" yoke to install, and also a 32" thwart that I *think will mount behind the yoke at some good point to hopefully add some stability.

Is drilling into a vinyl gunwale as easy as it seems? It seems like geting some stainless hardware and popping it in should be easy enough. I just want to make sure the sides are stable enough for good use.

Sorry for the dumb questions - this is new to me.


Yes it’s very easy.
For any additional thwarts you wish to add, you can see how to drill by looking at mounting holes for the thwarts that are already there. It helps to make a “dent” where you want to drill the hole, so the drill bit doesn’t wander when getting started. A sharp punch or awl will do the trick for that. Don’t cinch the bolts down too tight. There might be aluminum reinforcement inside the gunwale and there might not be. If there isn’t, just moderate tension on the bolt will deform the gunwale, so watch for that. The bolts don’t need to be super tight anyway.

You can determine the necessary length of replacement thwarts by measuring the old ones, but when installing additional thwarts where previously there had been none, determine the necessary thwart length by measuring the boat width at the target location while the original or replacement thwarts are in place. The boat may “spring” out of shape a little bit once some or all thwarts are removed, making measurements of boat width useless.

Be aware of the angles involved
When you install a center thwart or yoke you should take care to determine whether the boat has tumble home such that the end cuts on the yoke need to be beveled a bit for a good fit. Same with an intermediate thwart or carry handle although the affect of the tumble home on the necessary bevel is usually reduced as you move toward the ends and in fact there may even be some flare (opposite of tumblehome. Also the cuts are not 90 degrees when you are installing a thwart located away from the center thwart. Generally you can use the old parts to get the angles right.

will do
Okay – I’ve saved the old yoke to use as a guide, so hopefully it is reliable enough in length to use as a guide for the new one. The old yoke measures a *bit less than 36" - would you sand the new one to match exactly to the old, or would you assume the old (which has some rot and probably 30 years of use) has “contracted” from it’s original length of 36"?

I was planning to just use the new yoke as-is.

The new thwart measures 32" and is touted as being “for common old town canoes” including this model apparently for what that’s worth. I was just going to line it up somewhere behind the yoke (stern side) in a suitable place that seems like a good fit with the gunwales. Since that boat didn’t have one before I didn’t know a better way to do this.

Thanks again for your input – I had to look up “tumblehome” but understand it now.

Same as old one
Use your old thwart/yoke as pattern and cut the new one to the same size. If the bolt holes are not too rotted, you can clamp the two together and run a drill through the old holes and into the new. If carefully done you’ll be able to bolt the new one right in. If the holes are rotted, cut the new one to length and clamp it in place under the gunwale. Then run the drill through the existing holes in the gunwale and on through the thwart.

To install the extra thwart, lay it across the gunwale where you want it. Be sure it is square to the boat by measuring from either bow or stern to each side of the thwart. Clamp it in place and then lay a straight edge on top. The straight edge should be parallel the the gunwale edge. Mark the ends where they need to be cut. These cuts will be a little bit off square and will match the angle of the gunwale. Then slide the new thwart under the gunwale and clamp it into place. It is a good idea to leave a small gap between the end of the thwart and the hull to allow for air circulation. With the thwart clamped in place drill through gunwale and thwart, two holes on each side. Always use a flat washer under the thwart and a locking nut. If holes do not quite line up, drill them larger in the thwart until they do. Use #10 machine screws and a 3/16" drill to start.

New carry handles can be fitted the same way.

Good luck and happy paddling.


An extra touch…
To forestall having to do this again anytime soon I think its a good idea to slap a few coats of spar varnish on the end grain of the thwarts before the final installation. (First coat thinned ~20%) Prevents water soaking in and setting up the thwarts to rot again. I’ve never seen this done on factory jobs, but you and I don’t have to meet the production schedule that manufacturers do and can afford to take that little extra care. Just a thought.