Author Topic: Need opinion: removing dent from tank (Read 3101 times)

MrHellpop · « **on:** June 10, 2009, 05:27:36 PM »

Hey-o
I would love your guys' opinion on what the best way to remove the dent in my 77 750k's gas tank is. I've already stripped it down for paint, and decided that I can't live with the horrible dent from the PO on the right side of the tank. Please check out the picture!
I figure my options are:

1- Take it to a body shop and see how much it would cost to have them do it professionally.

2- Try the hot glue and stick of wood method.

3 - Screw it, repaint the tank, and live with it.

Also, anyone know if the 1977 750k tanks are double walled or single walled?

kghost · « **Reply #1 on:** June 10, 2009, 05:31:24 PM »

Single walled.

You could prolly bondo that.....

I generally pull the dents....but I'm anal.

I TIG weld on a piece of wire then use a dent puller.

If you want Perfect....get someone with experience to do it.....

If you want it to look good...you can do it yourself and learn as you go.

Might take a few attempts but its not hard.

fmctm1sw · « **Reply #2 on:** June 10, 2009, 05:36:26 PM »

Quote from: kghost on June 10, 2009, 05:31:24 PM

You could prolly bondo that.....

I've bondo'd bigger than that... Probably not the optimum way but mine held up OK...

MrHellpop · « **Reply #3 on:** June 10, 2009, 05:39:14 PM »

Quote from: kghost on June 10, 2009, 05:31:24 PM

Single walled.

You could prolly bondo that.....

I generally pull the dents....but I'm anal.

I TIG weld on a piece of wire then use a dent puller.

If you want Perfect....get someone with experience to do it.....

If you want it to look good...you can do it yourself and learn as you go.

Might take a few attempts but its not hard.

Crap, bondo was the other option I forgot to write down! I am planning on bondo-ing the couple of smaller dents, but I wasn't sure if it would work well for a larger dent like that.

Anyone ever pay to get this done, and how much did it cost?

Dave-and-his-550 · « **Reply #4 on:** June 10, 2009, 05:43:48 PM »

Dent it even more and do the other side to. Make room for clubman bars to fit when turning

No but seriously, someone mentioned a method where u fill it up with water, put it in the freezer and let it freeze, the water will of course expand and pop the dent out I guess? I've never done this. I also remember them saying not to put the gas cap on it, that way you wont rip your tank open, but it'll still expand enough to take the dent out. I dunno, ask someone else 'bout it!

MrHellpop · « **Reply #5 on:** June 10, 2009, 05:46:01 PM »

Quote from: Dave-and-his-550 on June 10, 2009, 05:43:48 PM

Dent it even more and do the other side to. Make room for clubman bars to fit when turning

No but seriously, someone mentioned a method where u fill it up with water, put it in the freezer and let it freeze, the water will of course expand and pop the dent out I guess? I've never done this. I also remember them saying not to put the gas cap on it, that way you wont rip your tank open, but it'll still expand enough to take the dent out. I dunno, ask someone else 'bout it!

This sounds extremely dangerous and possibly life threatening. I like!

mcuozzo · « **Reply #6 on:** June 10, 2009, 05:55:20 PM »

I recently removed a dent (smaller than yours but still big) using those silly hot glue gun Pops-a-Dent kits they sell at autozone, etc. Although it didn't remove the dent totally I'd say it reduced it by about 75%. Had to use it multiple times in multiple spots. Where I wouldn't have wanted to use that much bondo before, I think it's fixable know.

I tried to take pictures but I suck as a photographer. I have another tank to experiment on, maybe I'll get better pics next time.

Matt

Gordon · « **Reply #7 on:** June 10, 2009, 06:39:44 PM »

Quote from: Dave-and-his-550 on June 10, 2009, 05:43:48 PM

Dent it even more and do the other side to. Make room for clubman bars to fit when turning

No but seriously, someone mentioned a method where u fill it up with water, put it in the freezer and let it freeze, the water will of course expand and pop the dent out I guess? I've never done this. I also remember them saying not to put the gas cap on it, that way you wont rip your tank open, but it'll still expand enough to take the dent out. I dunno, ask someone else 'bout it!

I wouldn't try this with a tank I planned on using in the future. Freezing water doesn't just expand into any available opening (gas filler hole in this instance), and it doesn't know or care about the shape the tank is supposed to be or where any dents are. It expands in all directions and will at the least probably deform the tank, and at the worst will split it along the seams at the bottom.

Dave-and-his-550 · « **Reply #8 on:** June 10, 2009, 08:06:47 PM »

lol tell that to the person who recommended it!

B.O.X.N.I.F.E. · « **Reply #9 on:** June 10, 2009, 08:28:53 PM »

I've used the freezing method on my badly dented headers and I couldn't believe how well it worked. Sand & paint and you've never know it was there.

Having said that, I would never do it to a tank.

Sporkfly · « **Reply #10 on:** June 10, 2009, 08:44:53 PM »

+1 on the TIG welding. I luckily had access to a body shop's spot welder when I pulled my dent. Works better than any other method I've used. It pulled the dent to the point that I only needed a very thin layer of bondo to smooth it out where the metal had deformed slightly from the pull. I had one other very small dent on the top of the tank which I only used bondo on and I filled in the logo brackets as well. End result: pretty damn decent.

Side the dent was on, unfinished paint job. Pretty old picture of the bike as you can see

.

Mdub · « **Reply #11 on:** June 11, 2009, 02:56:37 AM »

Stick a broom handle in there and pop it out.
Sometimes it takes very little pressure to pop it out "oil can" style.
Be careful how much pressure you put on the fuel bung.

Gordon · « **Reply #12 on:** June 11, 2009, 06:46:39 AM »

Quote from: Dave-and-his-550 on June 10, 2009, 08:06:47 PM

lol tell that to the person who recommended it!

I just did.

Johnny5 · « **Reply #13 on:** June 11, 2009, 07:22:25 AM »

Eh, even after pulling the dent out, you'll still need to body fill it. I vote for Bondo only.

Chicago550 · « **Reply #14 on:** June 11, 2009, 07:50:05 AM »

Pulling would be the best way to go if you have the means and want perfection. If you just want it to look good give bondo a shot. I just repaired and repainted the dented tank on a CB350 and it looks good (and I'd never done body work before).

IHWillys · « **Reply #15 on:** June 11, 2009, 08:33:12 AM »

Just a little bit of heat can possibly get that dent to pop out. Use a propane torch and heat the dent from the outside edges in and watch it,as the metal expands it'll "want" to go somewhere.

Filler will likely be necessary regardless of method. Just trying to reduce how much filler at this point.

Ken

MrHellpop · « **Reply #16 on:** June 11, 2009, 10:23:58 AM »

Ok! I think what I am going to do is:
1- try to pop it out from the inside as much as possible
2- bondo it smooth
Thanks for all the input, and I'll post pics of the result if it turns out well! If not, I will deny that this post ever existed

Ps- I think filling the tank with water and freezing it is a terrifyingly bad idea ha ha no offense!

Rich W · « **Reply #17 on:** June 11, 2009, 03:39:17 PM »

Take it to a body shop and see if they can pop it out . If not bondo it .

Ricky_Racer · « **Reply #18 on:** June 11, 2009, 03:44:16 PM »

Now, about this freezing headers... How about some detail like, how do you do it? Do you put expansion plugs in the ends of the header? Weld up the ends of the header?

Will it work on headers with a welded collector? Do you use just water? How about sand and water?

There's gotta be a way to restore all these sets of dented headers laying around!

Thanks! RR

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Author Topic: Need opinion: removing dent from tank (Read 3101 times)

MrHellpop

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Rich W