Seat frame problem

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TX_yakker
Posts: 24
Joined: Thu Dec 27, 2012 9:11 am

Seat frame problem

Post by TX_yakker » Sat Mar 08, 2014 4:32 pm

Posted on here a while back, and I was hoping to have a finished boat by now so that I could show her off. I'm a first year dental student, and since I didn't quite finish the boat before starting school, progress is even slower now. I'm so close, but school comes first.

Anywho, my last step really is getting my seats installed. I have the seats made, and so I'm just tinkering around with height. I also need to make some wood spacers to hide my hanger bolts. Got out of class earlier than expected yesterday, so I set out to work on hanging my seats. The aft seat is hanging by each corner, as is pretty standard with these things. The front seat is a little engineered, due to my own miscalculation. I cut scuppers on the inwhale, and didn't calculate the "where" of hanging my seat. Thankfully, I wasn't too far off so my change in plan was to just have the seat rest on 2 blocks, and hang THOSE from the inwhale. Here's the picture (the seat is upside down, as you can see).

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So, I pre drilled my holes to attach the seat to these two sticks, and then went to putting the screws in. First screw went 99% of the way in and then sheared off. Shoot. Well, its holding the two pieces together, so i'll leave it… Lets do the next one.
Pre-drill, start the screw. This one doesn't go in quite as far, maybe 95% of the way down and I see the actual seat frame start to crack. YIKES!
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Naturally, I stopped and backed that screw out. I was using #10 1-1/4" wood screws, and I'm thinking I should have gone with thinner screws. Heres' my plan, let me know what you guys think: Because the seat frame will be resting on the two sticks, the weight distribution won't be the same as if one hangar bolt was directly through that piece of the seat frame. (i hope). So, I am planning to take something and open the crack a slight bit, put some wood glue down in there, and then clamp it back shut. Once it dries, the next step would be to go to an actual wood store (not home depot or lowes) and find some smaller diameter screws to embark on doing this again. What do you guys think?

Here's my back seat, installed minus the wood spacers for me to test out this seat height before I cut my blocks. Gotta celebrate the little victories too!
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Rod Tait

Re: Seat frame problem

Post by Rod Tait » Sat Mar 08, 2014 7:24 pm

Nice work on the canoe and seat frames. For the glue to clamp back together, I would use epoxy. Let some drip in there, maybe add a bit of filler to thicken the epoxy and then clamp. As for the screws, I only use bronze screws in my boats and they do tend to sheer off if one tries to over-tighten or the pre-drilled hole is not big enough or long enough. Did you or have you used a tapered drill bit? When using a tapered drill bit, the threads of the screw hold all through the hole. If you use a straight bit, the splitting usually comes from the larger diameter shaft being forced into the hole just as you tighten.

sedges
Posts: 290
Joined: Fri Jul 09, 2004 5:37 pm
Location: georgia

Re: Seat frame problem

Post by sedges » Sun Mar 09, 2014 1:09 pm

I think that #10 screws are way too big for the size of the frame material. #8 or even smaller would have been fine. All these would go is prevent the seat from falling off when the canoe is upside down and prevent it from moving around on the hanger rail. Also, I would make sure that your pre-drilling is removing enough material. and is deep enough. Those frames should not have cracked if the pre-drill was right.

Glue the cracked piece back together and fill the hole as well and start over with smaller screws and more accurately gauged predrilled holes. OR......

Another option that works for joining small, easily split wooden material is a solid copper rivet and rove. Elegant, simple and an easy skill to acquire. Since the holes go all the way through for the rivet there is no wedging pressure that can cause the material to split. You can usually find copper rivets and roves at most good hardware stores.

TX_yakker
Posts: 24
Joined: Thu Dec 27, 2012 9:11 am

Re: Seat frame problem

Post by TX_yakker » Mon Mar 10, 2014 11:01 am

Rod, thanks for the kind words! I have not used a tapered drill bit, mine are all just straight. I thought I used a large enough bit, but I think like Sedges said, my screws were a bit too stout for the simple function I need from them. I'll be epoxying the piece back together and filling the hole with some thickened epoxy, don't know why I didn't think of that first! Thank you guys!

Casey

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Cruiser
Posts: 614
Joined: Sat Apr 27, 2013 10:21 am
Location: Bowmanville, Ontario

Re: Seat frame problem

Post by Cruiser » Mon Mar 10, 2014 7:48 pm

If you are going to try the repair, I think I would lean towards unthickened epoxy. Glue seems to be a bit more viscous and doesn't seem to penetrate as far as the epoxy does (IMO). I had a couple of natural cracks in some cherry I was using, I forced the crack open a bit and used a glue syringe to add the epoxy as far in as I could get it,held it so it could flow all the way in, clamped after a few minutes, wiped off the excess and the repair was next to invisible as well.

Also, if you aren't using hidden hardware, have you considered just using a small carriage bolt there? Seems that would eliminate the stress and make the drilling a tad simpler.


Brian

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