OT 1945 18' Square Stern, half ribs, Paddling Canoe Restoration Project


Curious about Wooden Canoes
This is my first restoration project. Any advice, wisdom, tips, tricks, and encouragement is greatly appreciated. I’ve summarized my findings, thus far, and thoughts on how to move forward.

Build ticket: This is an 18 foot long, CS (Common Sense or middle) grade, square end paddling model with open spruce gunwales, ash decks, spruce thwarts, spruce seats, half ribs, a keel, outside stems, sponsons, a painter ring, a rowing seat and the oar locks were omitted.

So far, I've removed the keel and fiberglass from the bottom side of the hull, outer starboard gunwale and sponson. I plan on removing the port side sponson and outer gunwale this weekend. I’ll attempt to remove the old varnish thereafter. In the meantime, below is what I believe will be required to restore this canoe. Photos included. Please let me know if I’m overthinking or may have overlooked something.

1. The Front Stem is cracked on the exterior side and dry rotted at the top. I plan to repair or replace entirely with locally sourced white oak. Anyone have experience with this specific stem type? Joint in a new piece?

2. The Front Deck has rotted through on the starboard side and will require a new piece. Thoughts on using white oak for this piece? I also have a piece of mahogany just wide and long enough. Thoughts?

3. The Transom appears to have some dry rot and a few cracks. Are these typically reparable or is a new build recommended. Wood type? Did the original design have a drain plug?

4. At some point several ribs were replaced with ribs that are smaller in width than the original. These ribs were attached by screwing through the top of the keelson and into the rib. The hull tacks did not hold well, therefore, these particular ribs have shifted or pulled away from the inner hull body. Should I source white cedar for rib replacement or will western cedar be okay? Rib size appears to be 5/16ths.

5. Was the original outer gunwale one piece? Both outers have a scarf joint towards the bow. Maybe a repair was made at some point? Either way the Bow and Stern end of the gunwales are rotten. I will either need to replace entirely or scarf joint both ends. If a replacement is required, does anyone know how long of material would be required? Would white oak suffice?

6. Many planks on the hull bottom are cracked, punctured, gapped, rotted out, or simply missing large pieces. I plan on using western cedar to rebuild the hull. It’s certainly an easier material to source in Southern Missouri. The planks appear to be 5/32. I purchased a wester cedar picket sample from Home Depot. I was able to find a few straight grain pieces with minimal knots. Any danger with this approach? The pickets are a max of 6'ft.

7. If I replace the outer gunwale with white oak, should I go ahead and replace the inners with the same type of wood? There are several gouges on the inners. Maybe fill and sand instead of making new pieces?

8. The Stern Thwart is broken and the Bow Thwart appears to have been chewed on. I believe I have a piece of mahogany that could make two new pieces. I have no experience making thwarts, but I’m up to the challenge of trying. Any advice?

9. The Keelson. I've not yet removed the dry rotten planks from the underside to determine if the keelson is salvageable. I’d love to implement Dave Osborn’s Mahogany floor rack design- Absolutely gorgeous!

10. The Keel. I snapped the keel aprox 2’ from the stern when trying to remove from the hull. I could probably repair with glue, but making a new one out of white oak seems simple enough…. thoughts?

11. Both Sponson’s have some broken planks, but nothing to extreme.

12. New #6 canvas, fill and paint……no fiberglass!

I’m sure there are many more things to be discovered and discussed. Again, any thoughts or advice on build order would be greatly appreciated. Thanks.


  • Bow Thwart 2.jpg
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  • Deck 1.jpg
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  • Stem 1.jpg
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  • Ribs 1.jpg
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I’ll start..
splice in new piece on the stem id it’s only rotten a foot or less.
Go with new ash decks If you want to keep it original. I suppose white oak would be a close second.
transom is likely ash or oak. Rot is hard to fix. Transom is a critical area. Use the original for a template.
Get white cedar to replace the ribs that were replaced before.
Knots in red cedar, if real small could be hidden behind a rib. Otherwise find a straight grained 6x6 or beveled siding.
4x4 red cedar is usually too narrow for planks.
white oak will work for outer gunwale. If you can find it long enough go with one piece. If not, scarf joint it.
Make a new keel. Sounds like you have access to white oak.
I use #8 canvas on square sterns.
You the man, Dave. Thank you for the feedback.
Do you plain the planks down to the exact 5/32 or do you give yourself just a hair extra for sanding?
Dave I found a source for some solid brass tacks. What size do you recommend for planks to ribs? Would a 7/8'' oval head suffice or step-down to 11/16''?
I’ve always used 11/16. Northwoods Canoe, Island Falls Canoe or DB Gurney tack and nail company can supply you.
Hope all is well Dave! I have a friend driving to Canada with a trailer. He has offered to bring back some lumber for me. The build ticket calls for open spruce thwarts, seats, and gunwales. Is this still type of spruce still readily available?

If so, could you recommend rough stock size to rebuild the inner/outer gunwales, thwarts and sponsons outer trim?

How much and rough dimension of white ash for the deck?

OT 1945 18' Square Stern,​