# Repair dented Grumman canoe after its maiden flight?



## pybyr (Nov 20, 2013)

My Grumman 17 foot aluminum canoe apparently had nostalgic thoughts the other night about its aircraft ancestors during some particularly gusty winds, and went airborne and sailed several hundred yards down my field.

Remarkably, and thankfully, there is little sign of its misadventures- though it must've been a sight. Probably scared the daylights out of the deer that usually graze around that same area.

-but there is a medium-sized dent in the side, right near the center thwart, from just below the gunnel down to a few inches above where the waterline would be when it is in the water.

I am -hoping- that with the right technique and appropriate application of whoomp in the right place, it might pop back into shape, or mostly so.

But rather than wail on it with random hopes, I would like to solicit tips and techniques, in hopes of doing it once and doing it right, or as close to right, as feasible.

Anyone have experience or suggestions to share, either from canoes in particular or sheet metal, especially aluminum, in general.

Thanks!


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## semipro (Nov 20, 2013)

I'm always willing to hammer on the bent metal around my place. It sounds like basic auto body metal working techniques might work.  
You might consider giving one of the "paintless" auto body repair folks a call too.  They can do amazing things with metal.


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## ironpony (Nov 20, 2013)

My Dad and I are both retired toolmakers from Grumman. Dad worked on the original dies for forming the canoes. If you try to bang it out make sure you back it up so you do not over stretch the metal, sand bag works well. wood block on the inside to spread out blow from hammer face. I believe they were 6061 series al. so it should be workable. Is it a dent or a crease?? post a pic??


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## Jags (Nov 21, 2013)

Yes - pic please.  There are two different approaches based on if it is a dent or a dent/crease that has actually stretched the metal.


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## joel95ex (Nov 21, 2013)

I would find a paintless dent repair guy to do it.  will never know it was there. probably cut u a break on the price since he wouldn't have to get a perfect reflection


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## pybyr (Nov 25, 2013)

Been out chasing venison, and then it turned ferociously cold and I have not had a chance to get a photo during daylight (I do not think it would show up well via flash) will try to get a photo this week. Thanks for the suggestions, which I appreciate.


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## ironpony (Nov 26, 2013)

Jags said:


> Yes - pic please.  There are two different approaches based on if it is a dent or a dent/crease that has actually stretched the metal.


 


you have probably banged out a few dents in Grumman products that were meant to fly.


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## Jags (Nov 26, 2013)

ironpony said:


> you have probably banged out a few dents in Grumman products that were meant to fly.


I left that to the airframe guys.  I was busy trying to keep the zoomies inside the wires and magical boxes.


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## NRGarrott (Dec 10, 2013)

A couple of years ago I had quite the experience with a grumman canoe. I watched a couple of youtube videos on white water canoeing and decided I wanted to try it. I didn't own a whitewater canoe, but I had an uncle who kept a old flatback grumman behind his garage. I called a buddy of mine from the firehouse up, we picked up a case of beer, and headed to little falls on the Potomac. My buddy is a former marine and safety always come first for him. So we tied a 15' strap around the cooler with the beer in it, that way if we tipped, we wouldn't lose our supplies. I tied the end of the strap to the main support in the canoe that keeps both sides from caving in. The canoe launch area was actually separated from the river by a small island, so the water was pretty placid. When we launched we saw a serious looking kayaker in a 8' playboat paddling upstream so he could join the river the correct way, apparently the downstream way was pretty dangerous. We figured since a thunderstorm was coming in we would save some time and just take the canoe down the downstream way. We started off strong, using the paddles to fend off of rocks, and just generally enjoying ourselves. Pretty soon though it was time to beer up, and when i took one hand off my paddle it slipped into the river. Literally 10 seconds after i lost it, we started entering the crevasse that the kayaker decided to avoid earlier. Without anyone to steer the back of the boat, we flipped pretty quick and started tumbling down river.  I figured we were still in decent shape, until the cooler hit the end of the strap. At that time the cooler had enough momentum to bend the support. Without the support the canoe started coming apart and that's when I knew we were screwed. Eventually we managed to make it back to the pickup truck, but it was storming like a son of a groan, and we were out of beer.


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## ironpony (Dec 11, 2013)

good story, ship whats left out to me, I'll do the frame work, Dad can rebuil the powerplant. Then I will ship it to Jags so he can update the avionics. Might be able to avoid a repeat of this.

And I do not think it had anything to do with it being a Grumman canoe.

Retired Grumman employee here, I think it was used outside its designed flight envelope.


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