Canoe Repair

:( Hello all, I was wondering if anyone had any idea how to take dents out of an aluminum canoe. The dents are on both sides but close to where the bow comes together. Looks like the canoe was dropped on the bow and it caused the bow to be pushed down slightly. One rivet is broken off on the port side. The canoe is structually sound, just would like to know if there is a way to repair this.

Thanks Much!!!

I'd think that an auto body guy ought to be able to deding the dents with dolly and hammer?

We used a sandbag as a backing for knocking out minor dents on large aluminum surfaces when I worked on aircraft in the USAF.

Place the sandbag against the concave (dented in) side of the hull and gently knock the dent down with a rawhide mallet or small ballpeen hammer only until it's even with the surface. Don't use a claw hammer to do this. The face of the hammer is too flat and can cause fatigue cracks in the aluminum. The face of a ballpeen hammer is slightly rounded Don't use the ball end of the hammer, either. It only makes more dents. Only hit the metal hard enough to remove the dent a little at a time. If you begin to see impressions from the hammer, you're swinging too hard. The sandbag has to be held fairly solid against the surface for the method to work well.

If there is damage to any seams, or overlapped layers of metal this method won't work and professional help is advised. If there is a dent in a formed crease or folded area such as the bow point, sometimes a block of wood cut to a rounded taper point (like a tent stake) will help work out dents. Again, be sure the sandbag is firm against the other side.

Use care while working dents out of aluminum with a hammer, it might become brittle if done too long or too often. The result of hammering metals is called work-hardening. It's how you break the pull tabs off of soft drink cans, continued compression of the molecular structure of the metal and it eventually becomes hard and breaks.

Lastly, if there's a rivet missing, don't replace it with a pop rivet. It will never seal properly. Find a bodyshop repairman and get a solid aluminum rivet put back in it.

Hope this helps a little...

:)

Thanks!! all. The sand bag idea sounds good.

A word of caution - be careful on the temper of the aluminum. Most aluminum canoes are in the T6 temper, which has it's limits on cold working (hammering), and the hammer reworks are a bit more suceptible to cracking the material (where the dent edges are). If you can find the material and temper (maybe a pic too) - should be able to note a more detailed fixer-upper job.

Other than that - replace the rivet first and hammer away as MOturkE noted.

Unless the dent is causing some difficulty in paddling or is leaking, my advice is leave it alone. My Grumman is full of little dents, with one large one. You can do more damage trying to fix it. I leave the dents in as a sign of rivers past, sort of like scars. They add character.

Clint

Reading over the previous threads, I have to agree with the battle scar appeal and let it go. Maybe paint a band-aid across it for conversation attention :lol:

Meanwhile, my wife (who worked several years on Grunman mail trucks)says the sandbag and mallet is a good plan, but work it out very slowly.

Personally, I have strapped down the boat/canoe and used shaped wood and 2 ton hydrolic jack to slowly press out the dent. The rejoiced when Kevlar canoes hit the market :D

:o Thanks all for your advice. I may just leave it.Good point on the temper of the aluminum