Howie
Wooden Canoes are in the Blood
I have a problem with old splayed-out ribs distorting this canoe's shape. I'll get to the problem at the bottom of this Thread... but first some history:
Several weeks ago I was gifted a Rushton Indian Girl from my buddy Mike aka WCHA member MGC. The poor girl had sat unrestored since the early 70's but was in reasonable shape.

In particular note the break in the starboard inner rail by the rear thwart. I had thought this was caused by the thwarts being too short but later discovered they were original. I figure the 'kink' in this rail, and possibly the break itself, was caused by the ribs wanting to splay open. Anyway, after removing the outer rails I found that virtually all the rib tips were crumbling and that the inner rails were barely held in place. (Luckily this canoe has 'long decks', so there's a short thwart-like chunk of wood about 2 feet ahead of the decks that helped the rails retain their shape.) So I removed the inner rails and repaired them apart from the canoe itself.

Meanwhile I replaced 7 ribs and spliced in new ribs tips to virtually all the old ribs (while taking care to mark with pencil where the top of the inner rail should lie).
I think I reinstalled the repaired inner rails right: I clamped some rib blanks on both sides of the canoe just below the rib tips to act as battens to force the ribs to all bend together against the rails before I nailed them in place. This allowed me to tweak the inner rails's position so they were centered to the canoe and at the proper height.

And indeed, after I nailed in all the ribs everything looked just fine. For the first day. Then the ribs started to splay out again and the old inner rails weren't strong enough to prevent it. Here (pic below) is the canoe's profile when both thwarts are attached. Notice how 'pinched in' the inner rails are by the thwarts. The canoe's profile is really bad and irregular.
Here's the profile if I use a strap at the center of the canoe to simulate what the profile would look like if I added a center thwart. The strap is pulling the canter together by 1-1/2" to 2". This greatly improves the look, and I'm guessing this is how the canoe it is supposed to look.

And here's the profile if I detach the two thwarts and allow these areas to move out by an inch or more. Looks good to me...

So what do I do? Doing nothing isn't an option - the canoe looks awful with the original thwarts. Since the thwarts are original (well... I did remake the front thwart but it's to the same dimensions as the original), the ribs 'splayed out' over the past 50 years and don't want to go back to the shape they are supposed to have. I had hoped that the inner rails would be strong enough to force them back to their original shape - but nope. And no way am I going to remove the original inner rails and remake them with (stronger) ash.
So what to do to get the shape to look good?
1. Could steam help? I suppose I could use battens and straps to pull the sides to the shape I like, and then hit the inside of the canoe with steam and hope that the ribs take to their new shape when I remove the strap several days later. I figure I'd need to steam in small sections for maybe 15 minutes or more before moving to a different section. In addition I could pour boiling water from a tea kettle over the ribs. Don't know if that'd work though.
2. I could add a center thwart. But a 16ft IG never had a center thwart so that's not a good idea.
3. Or I could simply add some material to the ends of the existing thwarts and use the canoe in its more 'relaxed' mode.
Anybody have some thoughts?
Several weeks ago I was gifted a Rushton Indian Girl from my buddy Mike aka WCHA member MGC. The poor girl had sat unrestored since the early 70's but was in reasonable shape.

In particular note the break in the starboard inner rail by the rear thwart. I had thought this was caused by the thwarts being too short but later discovered they were original. I figure the 'kink' in this rail, and possibly the break itself, was caused by the ribs wanting to splay open. Anyway, after removing the outer rails I found that virtually all the rib tips were crumbling and that the inner rails were barely held in place. (Luckily this canoe has 'long decks', so there's a short thwart-like chunk of wood about 2 feet ahead of the decks that helped the rails retain their shape.) So I removed the inner rails and repaired them apart from the canoe itself.

Meanwhile I replaced 7 ribs and spliced in new ribs tips to virtually all the old ribs (while taking care to mark with pencil where the top of the inner rail should lie).
I think I reinstalled the repaired inner rails right: I clamped some rib blanks on both sides of the canoe just below the rib tips to act as battens to force the ribs to all bend together against the rails before I nailed them in place. This allowed me to tweak the inner rails's position so they were centered to the canoe and at the proper height.

And indeed, after I nailed in all the ribs everything looked just fine. For the first day. Then the ribs started to splay out again and the old inner rails weren't strong enough to prevent it. Here (pic below) is the canoe's profile when both thwarts are attached. Notice how 'pinched in' the inner rails are by the thwarts. The canoe's profile is really bad and irregular.

Here's the profile if I use a strap at the center of the canoe to simulate what the profile would look like if I added a center thwart. The strap is pulling the canter together by 1-1/2" to 2". This greatly improves the look, and I'm guessing this is how the canoe it is supposed to look.

And here's the profile if I detach the two thwarts and allow these areas to move out by an inch or more. Looks good to me...

So what do I do? Doing nothing isn't an option - the canoe looks awful with the original thwarts. Since the thwarts are original (well... I did remake the front thwart but it's to the same dimensions as the original), the ribs 'splayed out' over the past 50 years and don't want to go back to the shape they are supposed to have. I had hoped that the inner rails would be strong enough to force them back to their original shape - but nope. And no way am I going to remove the original inner rails and remake them with (stronger) ash.
So what to do to get the shape to look good?
1. Could steam help? I suppose I could use battens and straps to pull the sides to the shape I like, and then hit the inside of the canoe with steam and hope that the ribs take to their new shape when I remove the strap several days later. I figure I'd need to steam in small sections for maybe 15 minutes or more before moving to a different section. In addition I could pour boiling water from a tea kettle over the ribs. Don't know if that'd work though.
2. I could add a center thwart. But a 16ft IG never had a center thwart so that's not a good idea.
3. Or I could simply add some material to the ends of the existing thwarts and use the canoe in its more 'relaxed' mode.
Anybody have some thoughts?