: Thank for your interest. I haven't given up yet
: there are still a number of issues I plan to experiment with (see below)
: ---------------------------------

: They are pretty consistently in the curved section, despite the fact that I
: do a "prebend" using Cunningham's bending jig. I realize I am
: trying for a pretty steep bend (want a relatively flat bottom) but the
: degree of bend is still less than the 3" radius on Cunningham's jig

For this boat, I bent the ribs with a 1.75" radius. I'll have to look at Cunninghams book again, but I seem to remember questioning whether he was using a 3" radius as stated or a 3" diameter form.

The problem I found with a pre-bending jig is that since you're only holding the rib in the bent position for a few seconds at most, you get a huge amount of springback. That means more stress on the rib when fitting it. With the new jig (or a set of forms), where both bends are done once, the ribs cna be allowed ot cool until they're pretty stable (~3 minutes) and the springback is minimal.

: I am sure that is part of it. The particular boards I was using, yielded more
: slats/strips by using a flat grain orientation versus a quarter grain.
: After my first successful attempt (3 out of 3) I thought I was in a
: "go" situation to continue with this approach. Wrong. I will go
: back and try quarter sawn grain orientation. I still have enough wood
: left.

I tried flat grain ribs and they broke before I could get any appreciable bend in them. Never again.

: I use the prebending jig and then try to fit the rib free hand into the
: mortises. That is obviously when the problems occur. Using a bending form
: (similar to that on your web site) will be one of my next experiments. I
: don't want to make individual forms ( a la Mark Starr) so I will try an
: adjustable form approach first.

Well, I honestly have to say that I probably could have made a complete set of forms faster than the adjustable jig. The advantage of the latter approach is that I can use it for boats with different dimensions in the future.

: Don't think so. Have tried different speeds with different ribs

OK. The reason I asked is that the first time I tried bending ribs (over PVC pipe with no backing strap, I went too fast (as many sources encourage you to do) and the first five broke. Once I slowed down, they bend much better.

: First three were about 20 minutes, then went to 25 then tried 15. So after my
: first successful approach I went both longer and shorter in time.

That still sounds like WAY too long. I steam for 5 minutes and have done it successfully with as little as three. That's for 1/4" x 1" ribs. I have also bent ribs that were left in the steamer for 10-15 minutes. I didn't see any advantage to the longer steaming time.

: Borrowed Liz Leedham's "Lee Valley" kettle. Works great. Lots of
: steam
: one concern was that I was steaming too long. That's why I reduced time to 15
: minutes.

It would be worth trying a much shorter time. My current steamer setup put out a lot more steam than my old kettle did. But even with less output, I was still using 3-5 minutes successfully.

: It is definitely a "journey" you have to keep telling yourself. It
: is that feeling of satisfaction when you succeed that makes it all
: worthwhile (not to mention the fun of actually paddling the boat)

You bet!

: thanks for your support

Any time. We've all been there.