How to apply canvas to an upside-down canoe

[pathologist]

I plan to re-canvas a 17 foot Old Town OTCA this spring. The venue I have is perfect for the "clamped canvas hammock" method when dealing with a 15 footer. However, the extra 2 feet present a problem and I must use a "non-conventional" method. I have heard about others applying canvas on upside down canoes on saw horses. I think one end is anchored or held to the stem and tacking to ribs begins, not amidship, but at the opposite end. Can anyone give more details in stretching and maintaining wrinkle-free canvas. It sound like a two to three man job. I'd like to think I'm smart enough to figure this out but I know there are "tricks to the trade." Thanks, Pathologist

 

[Dave Wermuth]

Gil does an upside down on sawhorses without come-a-long method at Quiet Water Symposium. I've done it once with a rowboat.
1)make sure the hull is fair and without any lumps
2) lay out the canvas and check again for fairness and lumps.
3) staple to the stem part way around the stem as a temporary anchor for stretching. two or three staples.
4) go to the other end and stretch the canvas as much as you can with your foot or knee against the stem and put a couple more staples.
5) working from the middle begin to stretch and staple a few ribs on one side and the other side.
6) alternating sides work your way to the ends
7) pull staples and re do if there are puckers.
8) leave about two or three feet unfastened along the gunnel and carefully split the canvas along the keel from the end up to where it would come off the canoe.
9) pull and stretch one side lengthwise and staple to the stem. put the staple just beyond the center line of the keel
10) pull and stretch other side. put staples just to the far side of the staples underneath.
11) oops, don't forget to put bedding compound on the first row of canvas to seal the next seam.
12) but first, you have to trim the canvas you just tacked down.
13) try not to get ahead of yourself like I just did.
Ok, you've stretched the other side and stapled it just beyond the row of staples below. go ahead and trim that at some point too.
ANy puckers have to be fixed and usually there are more puckers on shorter canoes than longer ones. Pull the staple and re do it.
14) now do the other end on the stem as before
15) ALL that is left to do is to stretch and staple the last two or three feet you left undone along the gunnels. this will make it lay against the hull and not leave a space and take out the longitudinal stretch marks, and I think is one of those little tricks.
One guy can do it. I think you must go from middle to ends. starting at one end and going to the other doesn't seem to me to work, but I've never tried it.
Hope that helps. Let us know how it goes.

 

[Greg Nolan]

Gil's and Dave's method is similar to that given in the directions for the old Trailcraft kit canoes (except that the canvas for those was in two pieces) -- canvas stretched by hand down the center of the upside down hull, with the stretch held by staples in each stem at the ends, then fastening the canvas to the gunwales staring in the center and working towards the ends.

(On the Trailcraft, because the canvas was in two pieces, each piece, after being stretched by hand between the stems, was stapled to the interior keel at the same time as to the gunwale, starting in the middle of the hull, and alternating between fastening to the keel and fastening to the gunwale. The sides were done one at a time, because the canvas was in two narrow pieces. When covering a hull with one wider piece of canvas, there should be no need for fastening at the center of the hull -- just to the gunwales and stems.)

One person alone can canvas a canoe this way quite readily, although it involves a lot of walking back and forth and around the canoe.

 

[JClearwater]

I tried the “up-side-down” method for the first time three weeks ago when I put new canvas on my 16’ OT Double End boat. I had never done it that way before and wanted to give it a try. I used a come-along and wood clamps like normal. I did not try to do it without mechanical stretching help. It worked fine and I would not hesitate to do it again that way. Next time I will modify my sawhorses to make them taller. Normal height sawhorses are too low and they interfere with the canvas as it lays down past the gunwale. What I think I will do next time is modify the sawhorses with blocking and make them just wide enough to span the width of the canoe. Small blocks will be necessary against the inside of the gunwales to keep the canoe from sliding off the ends of the riser blocks. That way the canvas will lay down nicely past the gunwales. Other than that it worked just fine. My girlfriend helped me do it and we are still on good terms so it must be a good method.

Snowing outside – again.

Jim C.

 

[Dan Miller]

Next time I will modify my sawhorses to make them taller. Normal height sawhorses are too low and they interfere with the
Jim C.

I just slit the canvas so it falls either side of the sawhorse crossbar.

 

[Greg Nolan]

Of some interest on this question -- historical, not practical -- is an item now on eBay, item # 380768163890. It is a 1943 brochure giving instructions on how to canvas or re-canvas a canoe, and among other things, it calls for gluing the canvas to the hull as well as tacking it down. The brochure was put out by L. W. Ferdinand & Co., Inc., pushing Ferdico Canvas Cement and Filler.

All of the pages of the brochure are reproduced, and can be read if your browser can enlarge them a bit.

 

[JClearwater]

I just slit the canvas so it falls either side of the sawhorse crossbar.

Dan,

I thought of that but the sawhorses I was using have a 2x6 laid flat as a crossbar so I would have had to make two slits at each crossbar, 8 slits total, so I worked around the problem for this boat. If I was using "normal" sawhorses with a 2x4 on edge one slit would have worked. They are still too low so next time.....

Still snowing,

Jim

 

[Jan Bloom]

I have done 2 canoes upside down with stretchers, canvas pins and come along. Also Watched Gil canvas many "freehand" at the Quietwater Symposium. Upside down is easier than the right side up method for me. I do not have an adequate space for right side up. Slitting the canvas to fall either side of the saw horses makes a big difference. Where are you at? May be some members near by with experience and can lend a hand.

 

[MackyM]

Saturday, February 15th, there will be a canvassing demo at the Costal Southeast meeting in Melbourne, Florida.

 

[pathologist]

Thanks everyone and especially for the step-by-step procedure. In J. Stelmock's 2002 book, "The Art of the Canoe with Joe Seliga," pages 132-133, to overcome interference by the sawhorse crosspiece in stretching and tacking canvas, "Beneath the canoe, Joe places two supports built the exact width of the canoe just inside the sawhorses. Slightly taller than the horses, they support the hull and allow the canvas to slide down as more tension is applied."
Thanks, Pathologist

 

[Rod Tait (Orca Boats)]

And I have some videos on canvasing upside down on my web site.
http://orcaboats.wordpress.com/building-videos/cedar-canvas-canoe-repairs/

 

[Phil]

I recall watching a canoe canvased by hand by two people at a WCHA Assembly in the early 90's; it may have been done by Gil and a helper. One thing I recall was a recommendation by someone to wet the canvas to release the sizing and it would strech much easier. A light spray was all that was needed, then let it dry before attempting to attach it. Does anyone do this for hand streching? I don't believe it would make any difference if you use a mechanical method.

 

[Dave Wermuth]

I do not wet it prior BUT I will wet it and then apply an iron to shrink minor wrinkle spots. It generally isn't needed but once in awhile it is.

 

[tuckerman]

These are great videos. Thanks so much for posting!
One question: Do you think the procedure would work well with a Dacron substitute for canvas?

 

[Rod Tait (Orca Boats)]

Dacron is a whole different animal. I have done a few, and would prefer not to do any more, unless someone is paying me a lot. The Dacron was glued to the rib tops and around the ends with special glue. Then the material is heat shrunk and it shrinks quite a bit, so getting in on tight is not required. Then it has to be sealed with different products. The one I used was for airplane skins and was extremely toxic (could smell it hundreds of feet away - outside). The sealer also acts as a glue, so great care was taken to prevent the fabric from being completely glued to the hull. This I learned from another member here. Then the fabric was painted. So yes I put it on upside down, but no stretching other than by hand.

 

[samb]

Is it possible for anyone to describe how tight the canvas should be? Is it much tighter than I could pull by hand?

W/C canoe restorers are not to common in the UK, so I'm doing my boat from books and this forums guidance. I've got the canvas on order so should be canvassing in a few weeks when the insides are finished.

Thanks
Sam

 

[mccloud]

When we stretch canvas over a hull we grab the canvas with a "duckbill pliers", such as is shown on Rollin's site at http://www.woodencanoes.com/material.htm#tools Some of us have rounded a piece of wood and glued it to the top portion of the pliers so that it can be rested on the inwale, then the tool can be rolled over the inwale, as a lever on a fulcrum, without scuffing the inwale. When the canvas just barely begins to tear, you've stretched tightly enough, and some will say too much. At that point, put in the tacks or a couple stainless steel staples at the rib. Tom McCloud

 

[samb]

That's useful - thanks. How about tightness along the length of the boat before you start fastening? Is that similar - drum tight?

Sam

 

[mccloud]

Yes, pull it tight. It helps if the sawhorses are tall and the anchor points are low, so that you are pulling the canvas both lengthwise and downward. Put tacks or stainless steel staples into every rib tip. And when ready to fold the flaps of canvas across the stems, it helps a lot to have a couple of friends to pull those across and down while you work out the wrinkles before stapling into place. Tom McCloud

 

[samb]

Thanks.
The canvas arrived today so Maybe at the weekend i'll give it a go.
Sam