1947 Old Town 16ft Square Stern

[Michael Grace]

Craig, everything you described is spot on. From the hidden screws to placement of nails to how the sponsons were built onto the canoe, you're describing the typical Old Town method. Of course you won't be rebuilding from scratch but rather re-attaching. Canvas the canoe, tack on a strip of half-width canvas at the positions of the sponsons, re-attach sponsons, and re-attach. When re-attaching, just put a few screws through the hull and canvas along each side, and use those screws to locate their proper holes in the sponson. After pulling it tight to the hull with those screws, the other screws will find their holes. After stretching the canvas around and attaching at the top outer edge, and neatly closing up the ends, then fill the entire canvas including the sponsons.

About the wooden structure of the sponsons, yes you might need to do some repairs and fairing but there's no need to get them glass-smooth. Just like with the hull, you want everything generally fair, but the canvas and filler will hide minor imperfections.

Someone recently advocated for caulking the edges where the sponson meets the hull but as you could tell from dismantling yours, there is no need for this. As long as you do a good filler job, everything will stay watertight. When applying filler, give extra attention to working in into the canvas junction plenty the perimeter of the sponsons, and over the four ends (two ends of each sponson) where the canvas is folded over to close up. The filler will seal the joints and will neaten the appearance of the ends.

This process is well covered in Stelmok and Thurlow's book:
The Wood and Canvas Canoe: A Complete Guide
(https://www.woodencanoe.org/product-page/the-wood-canvas-canoe-a-complete-guide).

There was also a detailed description of sponson attachment and canvassing, with lots of photos, in Wooden Canoe. The story was called "Zen and the Art of Sponsons" (April 2016, vol. 39., no. 2).

Attached are photos of a sponson job, as described, from a few months ago. In the third image, made after the first coat of filler, note the very narrow gap between part of the sponson edge and hull. Just keep working filler all around the perimeter and into those junctions to ensure a good fill that disappears the junctions.

 

[CraigS]

I’m slowly making progress on this boat. I’ve been picking at stripping the interior varnish all spring and summer, and finally have that done! I had to go over the whole thing twice - with the first pass it took me nearly halfway to refine my technique for the best removal. I tried CitriStrip and Klean Strip, and decided I liked how Klean Strip Premium Stripper worked a little better than the CitriStrip. I found the key to getting the gunk and residue out was using the stripper afterwash and not skimping on it! I definitely used more 3M pads, stripper and afterwash than I thought I would too. The pads gummed up pretty quick, even after scraping away the stripper residue with a plastic putty knife. If I could have dedicated a whole day to it, it probably would have been more efficient, but I had to make due with 1.5-2 hour work sessions; with setup and cleanup that meant I was only stripping 4-6 ribs on one side of the hull at a time.

Next is stripping the outside of the transom, keel, outside stem and floor rack. I figure it’s probably easier to strip the keel while it’s still on the boat and held in place.

Planking looks OK, but I discovered a few splits in bottom planks near the stern. I’ve included a couple photos. Should I replace these planks since I’m there (once the canvas comes off), or is this not a big deal if I can make sure everything is fastened tight? I recognize that replacing them comes with the challenge of trying to stain new wood to match, so I’m hoping to avoid it, but I want to do what’s best for the long term - the plan is to use the boat, not have a showpiece.

With respect to wood color, you can clearly still see where the floor rack was. I was contemplating bleaching, but am leaning away from it because I don’t want to find myself chasing it over the whole boat to keep the color consistent. Plus, when the floor rack goes back in you’ll never see it. In my opinion, the subtle color variations from aged wood gives the boat character.

Obviously, I have a lot yet to do (canvas removal and sanding) but I’m thinking ahead and I have a loaded question - what to coat the hull planking with prior to installing new canvas? I’ve read about everything from boiled linseed oil mixes to thinned varnish to deks olje. Then I met a rep from Epiphanes at the Wooden Boat show in June who suggested using their Easy Flow product as a wood treatment. Has anyone ever used that product as a wood treatment/sealer? Documentation on it says it’s a blend of natural oils, but I can’t discern exactly what. I am currently planning to finish the boat with Epiphanes varnish and yacht enamel paint. I could just go the thinned varnish route, but I was hoping to possibly find something that penetrated the wood a little better, so I’m tempted to try the Easy Flow product.

Reading this forum has been a great resource, as have all the responses. Thank you!

 

[Worth Gretter]

Craig, the interior looks great!
Another option (just to make your choice even harder!) is TotalBoat Wood Sealer/Varnish Primer from Jamestown Distributors. I found it very easy to work with.

 

[Michael Grace]

Your stripping job is excellent. No need to worry about the split planks - they will be fine as long as they are well attached. You might add some tacks on either side of a split of one are very close to the split. As for the color under the floor rack, don't worry about that at all. It may be nearly impossible to make that ghost disappear and as you said, the floor rack hides it. However, consider giving the entire interior - seats, decks, gunwales - and both inside and outside the transom a treatment with a two-part teak cleaner/bleach (NOT household bleach!). This treatment will do wonders for the final appearance of the boat. Search threads here; there's a lot of discussion about these, the brands, and how to use them. Two great products are Snappy Teak-Nu and Te-Ka. Total Boat also makes one. I haven't used it but suspect it's just as good as those two.

You don't need to worry about any special pre-treatment of the wood. Epifanes varnish is an outstanding product. I've used every traditional spar varnish made by all the major companies, and Epifanes is now my first (only) choice always. Simply go by the Epifanes instructions for bare wood. Start with a coat diluted 50% with the recommended thinner, then gradually increase concentration of varnish relative to thinner until you're applying 100% varnish coats. This technique has worked perfectly on thousands of boats.

When you say that you wanted to "find something that penetrated the wood a little better", what does this mean? If you don't know how well any of these products "penetrates" the wood, then how to find one product that's better than another? Is there some kind of magic to "wood sealers"? I don't know, and none of the makers of these products won't say what exactly they are. They promote all sorts of benefits of these sealers, even without information to back ups the claims (I'm not knocking them; just wish we could make truly informed decisions). TotalBoat, as one example, promotes cost savings by using wood sealer because it "saves expensive varnish for the finish coats." Their sealer product costs $37.99 on their site, and they say you should use 2-3 coats. Their Gleam spar varnish is not much more at $47.99. A simple calculation shows that 3 coats of the sealer costs 14% more than 3 coats of their varnish thinned at 50%, 70% and 90% (90% varnish / 10% thinner). That's not counting the cost of thinner, but it's probably a break-even proposition altogether.

[Disclaimer - I like TotalBoat products, and they aren't the only company promoting mystery sealers.]

 

[CraigS]

Thanks for the encouragement about the stripping job! It was miserable and I felt like giving up at points because it was tedious and taking so long, but having finished with the interior, I think the results are worth it. I'm glad I'm not paying hourly for me to do it at my speed, as I sure have a number of hours in it!

Thank you for the suggestion on the teak cleaner. I will look into that for use after I have the outside of the transom stripped. That's a mess because it's peeling paint over varnish. Seems like several layers of paint too, so it's probably going to take at least a couple stripper applications. The teak cleaner seems like something that should happen before canvas removal to help contain it, so I'm glad I made a post and posed my questions before getting to that point!

Good to hear the splits in the planking are not a big deal. I will definitely make sure the planking is tight and add tacks as needed once the canvas is off. I assume small gaps between planks also aren't a big deal. However, based on the small gaps, it seems inevitable that any water splashed into the boat could find its way between the planking and canvas, which seems to strongly suggest protecting the wood planking inside and out.

By penetrating the wood I was thinking of the way deck sealers are described and promoted. I used a deck sealer in the past that soaked right into the wood almost immediately. I wouldn't use a deck sealer on a boat because I have no idea what it would do with respect to compatibility with varnish and wood color. Seems to me coats of varnish on the interior and exterior of the hull would seal the wood from water, which is the goal. So, I may use a different product, or may just stick with varnish. Buying one product does keep things simpler and even reduces the hazardous waste from any leftover product in the end.

The Epiphanes rep I spoke with recommended starting with Rapid Clear for the build coats since you can do a coat per day without sanding between. Then finish with a couple coats of the Clear Varnish. I haven't decided which route to take there yet (just use the Clear Varnish, or build with Rapid Clear first), but being able to apply a coat per day without sanding between seems like a good option if the results are good.