Real quick canvas question

[mmmalmberg]

I know I saw this mentioned in a thread not long ago but am not finding it.

While canvassing my OTCA I detected a slight difference in the amount of concavity on one side of each end vs the other side. When tacking the canvas along the decks, I was unable to pull it hard enough to bring it completely flat against the planking in that area, and the canvas is floating a good 1/16" off the planking for half a square foot or maybe a bit more.

My first thought was "close enough" and I finished up along the stems and trimmed canvas along the stem tacks. Then it was bugging me and seemed like it might have gotten a bit worse, so I re-pulled and re-stapled those areas. With the canvas stretcher I was able to pull it tight enough to just eliminate this, but after stapling it pulled back enough that it was still floating. I think the problem is too much tension lengthwise, as the concavity runs along the length while vertically it's flat.

I couldn't loosen the canvas at the stems since they were already trimmed, so I re-stretched/re-tacked again but same result, so I went ahead and filled about 4-5 days ago.

I'm worried this could make the canvas more vulnerable to a tear at some point against a rock or whatever. Should I be worried? Any suggestions? Blech.

I guess I didn't make that as quick as I intended

 

[Dave Wermuth]

Hi Mark,
I had an old town with that issue for 20 years. The fix, which I did not worry about, is that when you're canvassing, leave the outwale unfastened until after the stem is done and then as you stretch the canvas at the outwale the material will be drawn into the empty space. You're actually pulling it away from the planking by pulling at the stem.

 

[mmmalmberg]

Thanks Dave - Yeah I figured out the geometry of it after the fact Glad your canoe survived 20 years like that - hopefully this will be good longer than that!

 

[Dave Wermuth]

yep. It didn't seem to affect anything at all.