Two More Ribs Repaired

These ribs are the last ones to repair on the bow end.  The other ones that were less than perfect were salvaged by filling the defects with epoxy.  These rib tips will be covered by a cap strip, so they don't have to look good, they just need to be a good structural joint.  I tried to strip the last remaining finish in this area, but it still needs one more go with stripper.

I have been cutting back the broken planks so the new pieces end on a rib.  On these two, I kept two of the original fasteners.   The joints in the planking need to be staggered so two adjacent planks don't end on the same rib.

Here's a look at the skeleton from the inside of the bow. There are still several planks that need to be cut back, but those will wait until I have put some new planks on so I can keep the shape of the hull.

New Rib Top

Before:

After:

I cut a scarf joint and made a replacement rib top for the first of about 6 ribs (two at the bow and 4-5 at the stern end).  The tenon jig on the tablesaw works great for cutting the taper for the glue joint.

New stem installed

I beveled the stem blank on the band saw and did some hand planing to adjust the angle.  The angle varies from tip to keel, so it needs to be adjusted so the planks will lie flat.

The connection at the top has a #6 brass screw up into the deck.  The bottom joint is a scarf joint.  Both ends are glued in place with epoxy.  I took of a few more planking pieces, but I need to add new planks before I take anymore off. The first ribs aren't nailed to the stem, so the planks are holding them in position.  I don't know if there were nails originally, of if the rib ends were just nested up against each other.

New Bow Tip

I finally glued up the new tip of the bow. This replace the ends of the inner gunwales and the tip of the deck.  The deck tip is cut thicker than the original with a bit extending aft underneath.  This was the first time I used the West system epoxy.  It is a much slower cure than the typical 5 minute epoxy I've used before.  I opted for the slow cure hardener, which is usable down to about 60F. 

Here it is all cured up.  The seams will be covered with the thin cap strips along the edges of the deck. 

Here's what the old pieces look like.  It looks like someone stored the canoe with the tips resting on the ground and the bugs burrowed into it.

I cut the bow stem for a scarf joint to build it up with the new steam bent pieces.  I need to go from here to the tip of the deck with the new stem.

At the tip of the deck I cut back the inner gunwales to splice in some new pieces. These look simple, but getting everything cut at the right angles and fit together is proving to be a real challenge. The old pieces were full of insect holes, including the tip of the deck, which I also cut off.  The deck has cover pieces that cap the inner gunwales and rib tips, so these joints won't show.

Here's the other side. I had to cut it back further to get to good wood. I used scraps of ash from my failed stem bending attempts to make these parts.

Mortise and tenon seat frame

This is the bow seat frame.  I'm keeping the original pieces that go from gunwale to gunwale. They were doweled together originally, but I'm going to use mortise and tenon joints. Below is the mortising bit drilling square holes.  Another one of the really great tools my father bought.

And this is one of the new side pieces in the tenon jig on the table saw.  This is a great tool for precise, safe cuts on small stock.

And here are all 4 pieces almost ready to assemble. I still need to do a bit of final fitting and then it's time to glue the frame together.

Second stem blank

I bent the second stem blank today without any cracking.  The steam box got up to 205F and I steamed the blank for 2 hours.  This time I bent it from the deck end down to the keel, which worked better because the last bit was fairly straight and I had better leverage to bend it.  I tried sawing the bevel on the broken pieces from my first stem bending attempts on the bandsaw and it looks like it will work well if I set the bandsaw table to 15 degrees and saw to the corner of the square stock.

Steam bent stem blank

I took the stem blank off the form today and the springback was much less than the prior attempt.  Looks like it really took the shape.  Getting it up to a higher temperature and steaming for a longer time really made a difference.  I took off the compression strap and clamped it back on the form for safe keeping.  My form is wide enough that I can bend the next one and keep them both on the form.  If time allows, I'll try and bend the second one this weekend..

Second bending attempt

I changed the steam box setup to use a shorter connection to from the keg to the box and sealed the lid a bit better.  This time the box got up to 210F. The bad news is the insulation board started to warp. It's still holding together, so I think it will last through the end of the project, but if one were to build one for more permanent use, a layer of wood is necessary. 

The bending worked better this time. No cracking sounds and no sign of cracks after sitting overnight on the form.  The higher temperature combined with a 2 hour steaming seems to be what made the difference. I also had Laura helping clamp as I bent the stem.

Cracked stem blank

It looks like the 'good' stem I bent yesterday also cracked.  I'll need to try again.  I still have two unbent blanks, so in theory I have enough material.  I can use the cracked one as practice pieces for the next step, which is cutting the blanks to a vee shape on the bandsaw.