It's Official - my '51 OTCA project

[Fitz]

back side is the side that's not cracked

Ahhh! There is my problem with the back side repair. After all the time spent restoring a canoe, those gawdawful cracks are left staring you in the face through layers of new gleaming varnish. I have used the method before way up under the gunwale like your bad spot and I would not hesitate to use it if I were you. I think modern epoxy makes the butt joint less of a problem. You can also play with the shape of the mortise/spline to make it less of an issue.

Another fix is to scarf a new rib tip on. This removes the offending crack (you are left with a nearly invisible glue line) and judging from the photos, you would not lose much rib? There are lots of tutorials on the forum about scarfing rib tips.

 

[MGC]

Honestly this seems like much ado about nothing. If that is the lone rib in the area and the only damage and presuming the inside rail is perfect, just leave it and move on. There is no way that you can flex it enough to open it up enough to get glue or epoxy into it unless you separate it from the rail. It's overall impact on the integrity of the hull is mice minutia. Unless you are concerned about the cosmetics why bother? If you plan to squeeze in glue you obviously aren't.
WRT steaming vs. soaking....It takes very little time to make a steam box. Anything (a PVC tube) that holds steam will work. Bending steamed wood is far less messy than the noted towel method and the results are almost guaranteed. And, on the chance that you do end up installing the rib upside down or backwards you can just remove and put it back in the steam to fix your mistake....not that I've ever done it

 

[Dave Osborn]

MGC is right in my opinion on the rib crack. This little crack doesn’t need a backside repair. If it were in my shop, I’d syringe a little glue in where I could and leave it as is. Cracks don’t offend me on vintage canoes. They are part of the legacy of your canoe.
I do a lot of backside repairs. In my mind, I’d rather see the crack (knowing that the backside repair has given it integrity) than see a brand new piece of wood that is difficult to match in patina and color. I do replace ribs if they can’t be adequately fixed, but I can do a backside repair in a helluva lot less time than replace a whole rib, however it’s not the time that matters to me.

One thing you will find with this group is that we all do things differently to get to the same end. Sort it out in your own mind, do what you think will work best for you.

I think I may have seen where you mentioned steam bending gunwale tips and stem tips. Not sure how long the pieces are that need replacing, but I’d suggest that if they are short that you just cut them from a price of wood rather than steam bending them.

 

[Dan Lindberg]

Some folks make the backside with tapered ends to avoid this.

What I'm not in love with in the backside repair is that a mortise like that leaves you with effectively a square butt joint at either end,

As for trying to glue a crack, for those who have done it, how do you get it clean?
I have tried epoxy, just pushing it in an expanded crack, and when I went back to check, the joint had no strength.
I haven't tried it sense.

On this one, based on just the pics, with the 2 cracks, I'd probably scarf a new end on.
BTW, here is where old ribs can sometimes be used, to match the grain and color of the old.

Dan

 

[Craig Johnson]

Honestly this seems like much ado about nothing. If that is the lone rib in the area and the only damage and presuming the inside rail is perfect, just leave it and move on. There is no way that you can flex it enough to open it up enough to get glue or epoxy into it unless you separate it from the rail. It's overall impact on the integrity of the hull is mice minutia. Unless you are concerned about the cosmetics why bother?
I agree. It has been my belief that if it is a crack, not a break, and there is no deformation in the hull, that you will introduce more weak points with any kind of repair. Say you have an 8 or 12 foot piece of planking attached to every rib with 3 or 4 tacks each. If you cut out a short section of planking or maybe 2 in order to expose enough rib to do a backside repair you are now left with 2 or 4 butt joints in the planking which I believe will I’ll weaken the hull more than the original crack. I have taken out ribs that had a crack in much more critical areas than yours and was amazed at how much strength the rib still had at the crack. I also would rather see a crack than new wood. just one hobbyist’s opinion and there are many more but yours is the one that matters and it will be fine whatever you do. Have fun.

 

[Dave Osborn]

If you feel like you really need to do something with this little crack, you can scarf in a new rib tip as Dan suggests.
As far as backside repairs go, you can diamond shape them or radius the ends to avoid that sharp butt joint edge.

 

[mmmalmberg]

Honestly this seems like much ado about nothing. If that is the lone rib in the area and the only damage and presuming the inside rail is perfect, just leave it and move on. There is no way that you can flex it enough to open it up enough to get glue or epoxy into it unless you separate it from the rail. It's overall impact on the integrity of the hull is mice minutia. Unless you are concerned about the cosmetics why bother? If you plan to squeeze in glue you obviously aren't.
WRT steaming vs. soaking....It takes very little time to make a steam box. Anything (a PVC tube) that holds steam will work. Bending steamed wood is far less messy than the noted towel method and the results are almost guaranteed. And, on the chance that you do end up installing the rib upside down or backwards you can just remove and put it back in the steam to fix your mistake....not that I've ever done it

I'm glad to hear support for this concept - I'm between "squeeze and leave" and possibly that then adding some smaller stiches across it. Actually there appear to be two cracks, one above the other. What you said is even more true because this rib tip is close to the deck so has plenty of support from the rails.

I do appreciate the hand-holding through this, my first canoe and first canoe repair work. I do lean more toward perfectionism, not obsessively but just an inclination to do things as well as I'm able. So, thanks

 

[mmmalmberg]

If you feel like you really need to do something with this little crack, you can scarf in a new rib tip as Dan suggests.
As far as backside repairs go, you can diamond shape them or radius the ends to avoid that sharp butt joint edge.

A great improvement. I've even been considering diamonds on the front... I did triangles once on a guitar that someone drilled a bunch of extra holes in - they practically dissappeared.

 

[Dan Lindberg]

Remember that just about every thing you do is replaceable, meaning if you do something you don't like, you can always replace it and do it over.
On the 1st canoe/rib I did, it took 3 tries before it was in right.

Dan

 

[mmmalmberg]

Some folks make the backside with tapered ends to avoid this.



As for trying to glue a crack, for those who have done it, how do you get it clean?
I have tried epoxy, just pushing it in an expanded crack, and when I went back to check, the joint had no strength.
I haven't tried it sense.

On this one, based on just the pics, with the 2 cracks, I'd probably scarf a new end on.
BTW, here is where old ribs can sometimes be used, to match the grain and color of the old.

Dan

However it goes, I'll take my time deciding. I don't have a "spare rib" so to speak but can find some correct wood I'm sure. I'll take a picture showing a wider view of the location to see if you think it has any bearing on the decision... Thanks Dan

 

[mmmalmberg]

Here's the location of the rib cracks relative to the front deck. It does look like any repair will not be super visible. That's the lower of the two cracks that's visible.

 

[mmmalmberg]

Backburnering the rib for the moment, and my overall take is I'm not likely to make it worse in any case.

Moving to my first repair which will be the starboard inwale which has a crack almost 2/3 of the way through the outer side. Here's the crack and a concept for a "back-side" repair that would be very straightforward to execute.

 

[mmmalmberg]

 

[mmmalmberg]

Now I just need some glue Actually I have some TBIII but thinking of finding some gflex since that seems to be well regarded hereabouts.

 

[monkitoucher]

I kind of think of the rails as the spines of the canoe. I could see that popping free with a little stress. In fact, my OTCA had a similar repair that did pop. Mabe your's won't. Who knows. I kind of go back to my previous statement. If it were me I'd have those rails replaced altogether.

 

[mmmalmberg]

I kind of think of the rails as the spines of the canoe. I could see that popping free with a little stress. In fact, my OTCA had a similar repair that did pop.

I was somewhat thinking that with the ends of the splice being in the middle of ribs they'd be held together somewhat between the rails. But to be sure I've imagined it popping and don't doubt that as a possibility. At the same time, to make a new rail I'd likely have a splice in the middle of it anyway, yes? Maybe a better one than this I suppose. I will continue to ponder - I just needed to actually do something rather than having progress stop while my brain turns over every possibility. Worst case, I suppose I could do all the repair work on the rails now and then still replace them down the road. I'd have at least learned something Understanding that now would be an easier time to get it right. Thanks for your thoughts, it really is helpful for me to hear the ins and outs of it all

 

[mmmalmberg]

I probably should have the angles flipped so the ends of the splice are trapped in the rail. Somewhat more difficult but it would be unlikely to pop out.

 

[Dan Lindberg]

Remember for a proper structural joint you need something in the 6-10 to 1 taper.
That looks like just a bit over 1-1. No strength at all.

Dan

 

[mmmalmberg]

Remember for a proper structural joint you need something in the 6-10 to 1 taper.
That looks like just a bit over 1-1. No strength at all.

Dan

Right and I wondered about that with the "backside" rib repairs which have no taper. The section of this that's parallel should be plenty strong, so the problem is a focal point for stress at each end. Some sort of revision seems in order, thanks

 

[Rollin Thurlow]

One of the problems in trying to pound the bolt out, is that the rail flexes or moves so much that that the pounding force is being wasted. Also when the bolt comes out it tears some of the wood fibers at the top of the rail. I found that using the clinching iron, set on its side, so that the hole in the middle of iron surrounds the head of the bolt and holding the iron tight on the rail does a lot to steady the rail and the pounding force is much more effective. Of course the treads have to be protected but this works just about in all stubborn cases with out any damage.