Since there's a fair number folks with on the list metal-working BTDT, I
thought I'd ask for advice on a non-LBC project.
I spent last week in Big Bend National Park with our Boy Scout troop (yes
it was a GREAT trip!). We took a trailer load of canoes and floated some
canyons on the Rio Grande. Some of the boats were old Grumman aluminum
canoes (GAC content). On the last day, two of the youth broached their
canoe across a rock in Colorado canyon and it filled partially with
water. Before I could get up there with the rescue line, they had jumped
on the bow to free the boat and had bent the canoe's keel, which is a strip
of T-shaped aluminum about 1/8" thick, that is riveted to the bottom of the
boat. We managed to salvage the boat and towed it 7 miles to the take-out
point.
I'm wondering if any of you folks are willing to offer advice on
straightening the keel. The bend is about 3" in the vertical direction
(towards the inside of the boat), and about 2' on either side the keel is
straight; so overall the bend is a very shallow V. I've thought about
turning the canoe upside down and pressing it upwards into a pair of 4x4s
running the length of the bottom alongside the keel, using a hydraulic jack
to press upwards on the bulge. A friend who salvages railroad cars has the
timber and two backhoes that we would use to hold down the ends of the
4x4s. He also has a 30 ton jack. I have a section of railroad tie that we
can use to distribute the load across the bulge, so that we don't just
punch a hole in the bottom.
Mechanically it seems like it may work. But if anyone else has a bright
idea I'd appreciate hearing it.
What about heating the aluminum to make it more pliable? I know one can
heat iron and mild steel to work it back into shape, but I don't know about
aluminum.
Also, would this kind of straightening job be easy for a frame repair shop?
Thanks in advance.
Cliff Hansen
hansenc@flash.net
1966 TR-4A CTC 64615L (no progress since last year, been too busy)
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