Canvas filler

[Dave Osborn]

I’ve had the issue twice. Both involved high humidity when I canvassed. I think cedar expands a lot in high humidity. Now I never stretch unless the humidity is under 50%. I have a dehumidifier in the shop.
Rather than start over, I pulled the staples and stretched it again. It was easy on the sides because I never trim the canvas until after paint, but the ends were tricky. BUT it did work out fine...
You might try that as opposed to starting over.

 

[dtdcanoes]

WOW.....wrinkles and worse than looking in the mirror.... I check for the degree of stretch this way : I have the come along tightened down and the posts against the ceiling for downward pressure. Then I do a walk around to make sure that nothing was captured under the canvas during the process eg. a spare tack, a loose tack in a plank not attended to earlier, any unacceptable hull surface not properly corrected, even a stray canvas thread, which can be removed without much trouble wherever it is ( previous thread ). Now I check the tightness this way : I bend over the wale to see the under side of the hull midships . I clench my fist and support the end of my thumb with the end of my index finger. I press my thumb nail against the canvas with moderate pressure at, say 30 degrees and drag it slowly toward you all the way to the bilge . I find if the canvas is tight enough , you will get a LITTLE wrinkle ahead of your thumb as you move along. A little wrinkle will disappear when you tack the canvas. You can check for this by putting in a few tacks midships on both sides., and be satisfied we are tight, just right, when you can't get a wrinkle without suffering a good deal of pain to the thumb.
If you are using some sort of a canvas pliers to tighten the canvas at the rib, you will quickly dial in that sense after the midships check. I don't think one ever forgets that feel. There is a little more to the above, but you have the idea by now.
Have fun...Dave

 

[Michaux Hiker]

It has many more wrinkles than me! Anyway this canoe project will be the death of me! My wife was almost crying when she saw all the winkles after I spent so long in restoring the darn thing. I'll try and re-stretch it and see how that goes. I did trim it but not to the edge of the planks so I should have enough to grab the pliers. One question. Should I remove all the tacks including ones at the stems or just do a section at a time, like 3-4 feet? Wrinkles are parallel to the ribs and a few diagonally across the bottom. It was over 90 degrees when I stretched the canvas and now is in the 60-70 so like Dave said the I can blame the humidity!

Thanks, Mike

 

[Dave Osborn]

I think I did a few at a time.
Looks like you will need to pull from the ends to get those pulled free. Not much to grab on to, but there is obviously some slack there.

 

[dtdcanoes]

I too would be conservative as you try to get home. The wrinkles are probably because the canvas was too loose lengthwise when you tacked it down I would consider taking the tacks out at the stern only and along the sides at this end only to the point where the wale starts the curve the the stem. Now you can really grab both sides hard or not and see what effect you have on the wrinkles. You may find that pulling first along the keel line will tell you a lot about how much force applied where will get the wrinkles out. If you see you may be on to something try clamping both sides to hold it there ( she will help with this after wiping away the tears ) and maybe you learn more when you release the canvas another foot back on both sides. This challenge won't be the death of you, but you will be smarter and wiser. Just go slowly and do what Rollin does....when the goin gets tough ....he just stands back a few feet , with folded arms and a steely stare, and finally makes some sense of it.... And later take her for ice cream and say nice things. Have fun

 

[Michaux Hiker]

My wife is much smarter than me! When I first mentioned the wrinkles her first response was "Can't you just pull the tacks out re-stretch and re-tack" Go figure... I may have trouble getting the tacks out of the stems as they have a nice buildup of filler. Guess go slow in removing the tacks. I'll try your suggestion of pulling along the keel then near the bottom at the tack line. Most wrinkles are between the ribs near the tack line.

Next couple of days are going to be hot and humid so will wait till later next week. A few days of camping early next week. At least I won't have to walk by the canoe five times a day and shake my head wondering how I am going to fix it.

Thanks, Mike

 

[Michaux Hiker]

Finally finished!! Launch day was November 26th. Probably hasn't been on the water in decades. Already put a few scratches on the bottom.