Shear Planking

[Dave Aukes]

69 years ago the Peterborough craftsmen ended up short with the planking at the shear line so they tacked narrow peace's of plank material to the raise the shear line. These little strips didn't make it through the fiber glass cloth removal.
I am now at the point in the rebuild that I need to deal with this issue. What is the best way to deal with this shortage.

 

[1905Gerrish]

Are there any options other than what the original building came up with? You could always scribe a line and take a bit more off but why make more work.

 

[Michael Grace]

Agreed - just add pieces back to match those that were removed when removing the glass. Pretty straightforward. Why make it more difficult?

 

[Worth Gretter]

Dave, you may worry that those thin strips may not be strong enough, but with the ribs, canvas, and gunwales there will be plenty of nearby support.

 

[Dave Aukes]

Yeah, this 18 ft square stern canoe has 65 ribs spaced 3/4 to 7/8 inches apart. So it seems like these narrow strips of plank will be taking a lot of tacks during canvasing. Red cedar these days seems to be prone to cracking, predrilling all holes seems to prevent most cracking. But predrilling through canvas during stretching would be a real pain.
The strips that came off were all splintered from tacks so with that and the fiberglass cloth removal, everything mostly turned to toothpicks.
I think a wider plank would hold up to all those tacks better - so I'm trying to come to terms with that.

 

[Gil Cramer]

For a wider shear plank the two most obvious options are; replace the top existing planks with wider planks, or lower the inwales.

 

[Rollin Thurlow]

Use 1" wide plank to finish the planking. Use canoe tacks only if they can be clinched below the inside rail. Predrill the planking and the rib. If there is not room enough to use a canoe tack, apply a spot of tightbond yellow glue to the rib and nail into the rib with a small steel nail. Let the glue dry, remove the nail, trim all the planking so its 1/4" below the top of the inside rail.... Viola, your done!

 

[Worth Gretter]

Another option is to use Dacron instead of canvas. The top of the fabric would be attached with heat bond tape, not tacks.
My experience with Dacron is at https://forums.wcha.org/threads/anybody-ever-use-non-standard-canvas-thicknesses.19113/post-102428

 

[Dave Aukes]

Okay, thank you everyone for your feedback.
It has taken a while to think through this, and I think Rollin's suggested procedure will be the best fit for my situation.

Also, Worth I'm going to look into the Dacron option, so I might lean on you later for some guidance. Not sure how long Dacron has been used for this application so I'm wondering if any information has been gathered from repairs or rebuilds on older Dacron covered canoes. I have read some about its durability and most sounds positive.

 

[MGC]

A canvas is far more forgiving on an old hull that is a bit rough. Dacron wants a pretty fare hull. I would definitely use it for a new hull and be somewhat selective about what older hulls to put it on, based upon my experience with a somewhat rough hull.

 

[Dave Aukes]

Has anyone replaced the covering on a Dacron covered canoe that has been in service for many years? If so what did they find and what are their thoughts?