Removing a huge gas tank dent

I know this one comes up a lot, but what's the best way to remove this tank dent. My backup method is welding rods and pulling it out and repainting, but I was wondering what you guys think of trying to push this out from the inside with a bent rod of some sort? The picture isn't great, but the dent is huge and the edges are relatively smooth, not a sharp kink.

 

ive never had any luck trying to push them out it always makes out dents in the tank. thats a big dent your probably gonna have to do the welding rod trick. im curious also to see if anyone knows of a good way . one thing in your favor you might be able to get at it thru the petcock hole best of luck

 

I don't think you'll be able to reach it with bent rods and apply enough force to move it. The tunnel is pretty close to the top.

You could try dry ice. It'll freeze the metal causing it to shrink and the dent may pop back out. Another option is drain the fuel, plug all the holes and fill it with water then freeze. Water expands when frozen and should push the dent out.

Then there's those dent puller suction cup things at the parts store. Never tried them.

Or the welded studs and slide hammer.

Or carefully smash the other side in to match.

 

Matching dent would be so old school modder right?

 

Has anyone ever successfully used the freeze method. I have a dent in the center of my DT175 and would like to try, but I am worried about it expanding the sides.

I was thinking that if I froze layers from the bottom up until I was about 3/4 of the way to the top, it would be safer.

Other option was to fill the dent with fiberglass.

 

another option similar to iwingameovers frozen water is air pressure. I have a small dent I might try to remove if you have success with yours. Good Luck

 

I've never done it but read about it.

Metal has a memory and wants to go back to it's previous shape so the sides and rest fo the tank which was most likely formed by a press creating heat and pressure are far more stable than the more recent dent. The dent being weaker would/should move first if pressure is applied to it.

 

The freeze method will ruin the Tank.
Frozen water is capable of destroying an Engine Block.
Those seams holding the Tank together will be split and the Tank destroyed.

Rent a Spot Rivet Welder.
Buy an extra Box of Rivets.

The Rivet Welder attaches a Copper Rivet to the Dent.
The Tank is not perforated.

Welding Rivets to the Tank and "Pulling-Out" the Dent a little at a time will bring-out the Dent to where it can be refinished with some Standard Bodywork processes.

Work the Dent out from its edge, ... NOT the middle.
Bring the edges out all the way around until you are left with a minimum area left that will require Body Filler.

http://shop.vendio.com/BROADSTONEPRODUC ... 1277279762

 

Everything I've read about air pressure or freezing water has said you have a higher chance of blowing the seams than the dent. I don't want to repaint, which will be necessary after the weld and patch, but I'm guessing that's the only reliable way. I was mostly wondering if anyone has ever successfully pushed one out.

I haven't had the tank off yet, but that is the side with the petcock so I wonder if the access from there would be enough.

Dry ice on the outside sounds like it's worth a shot. It's cheap and probably won't damage anything.

 

Could just be the lighting or angle, but rivets and a slide hammer are about the only thing you can do with a dent that big. And the odds of getting close enough to even be worth body working are probably slim to none. Buying another tank is your best bet.

 

Even if you get the dent to pop out it may crack or chip the paint, somethings got to give. So you'll probably have to repaint anyway, I say try the welded rods/rivets and the slide hammer and tell yourself that dents just add character.LOL

 

this is worth a try curious if it works

http://www.autoblog.com/2007/05/29/vide ... essed-air/

 

That's cool! I don't see why it wouldn't work on a tank as long as there aren't any creases. It's sure to get most of it out.

 

That Hair Dryer Trick ... only works on "Pushed-in" type dents.

The hit on this Tank is DAMAGE, ... with creases that aren't going to "Pop" out.

You can Drill access holes opposite the damage and "Pound-Out" the Dent with a Hard Wood Dowel that has had it's end sanded to a half-round dome.

Keeping the number of holes drilled to a MINIMUM is key.
Each hole will require a Welded or Brazed-on patch.
You'll have to:
Pound-out the dent
Grind the spot
Apply MarGlas Filler
Sand the MarGlas
Skim Coat the MarGlas with Bondo
Sand and Finish the Bondo
Weld on Plugs
Lead-load welds
Sand the whole Tank
Prime
And, ... blow-on the Color.

Or, ...

Find a USED Tank and have that Finished and Painted.

 

Best Solution

 

i thought the hair dryer was a bit far fetched for a big dent but if you had the stuff lying around was worth a shot

 

Hair dryer solution costs nothing and takes 5 mins to try.. I doubt it will work, but if it costs nothing and the time is minimal, why not give it a go.

The paint on this dent has become distorted, chances are that it'll loosen and flake off.. Only thing you can do to sort this out is be prepared to redo the paint. Then you've plenty of options.. I like the non-perforating rivet method because it's the least damaging to your tank. Then you've got the welding rod method, but there's a chance you'll go through the metal, then you can drill a hole on the opposite side and bash it out and finally, you can drill a hole through, put a threaded rod through the hole and with a bit of fiddling you can get a large washer and nut on the rod, and pull it out. This is less likely to make an uneven surface than either the bashing method or the welding rod or riveting method, but you've a hole in your tank which needs sealing.

Anything that involves putting a compressed gas or liquid or ice in the tank is doomed. First, sealing the tank is going to be a pain, second, the gas or liquid exerts an even pressure on all parts of the tank, so the thing that's going to give is the weakest part of the tank.. Most likely the 25 year old seams, not the dent. Don't do this unless nothing else works and you were going to write the tank of anyhow.

The method I use most frequently and have had a huge amount of success with is to get a large amount of filler and some wet and dry paper, and leave the dent as it is and fill it. Since you don't have any creases in the metal, it's the most likely method to work long term without any on going problems. Do the job properly and you won't notice it, you've probably lost maybe 10 miles worth of petrol in the usable space that the dent takes up, so really it's just character building Fill the dent with thin layrs, rather than trying to do the whole thing at once.

Good luck.

 

I've been watching ebay for replacement tanks since I got the bike, but so far they've all been pretty battered and still sold for quite a bit.

I'm going to try hair dryer + dry ice and expect it to do nothing, and then just live with it until I can afford to take it somewhere. I'll let them recommend whether they should pull it out with welded studs or just bondo over the whole thing, but I think those are the two most realistic options.

 

Mate. If you're going to go to the expense of someone else doing it for you, have a go at doing it yourself first. You're unlikely to make the repair bill any bigger and you might just save yourself a few hundred bucks.

 

I'm a cheap ass, so if it's going to be expensive that dent is staying. But I can't paint it myself, and was assuming the dent pull would be cheap if I'm having them paint it too. I've never welded before, and probably not a good idea to learn on a gas tank. I could bondo over it myself, and maybe that's the best plan.

 

I think so. In the end, it's your tank, but everyone posting on here had to learn at some point, even those that think they're experts and take the Mick out of us that know we aren't.

You can't learn by giving your tank to someone else. You can only learn by doing it yourself and making mistakes.

 

I have had some limited success with one of those hot-melt glue devices (mine is the Ding King). Glue a threaded post to wherever you want to pull, position bridge unit on top of pin, screw on knurled knob until glued pin pops off. It works real well if there is no crease; I have a tank currently that has 2 creased dings and I've gotten it to the place where filler can now be applied. Completely pulled other shallow dents (and didn't remove the paint). It's about $30 or so at most auto parts stores and has everything in the box you need (hot-melt glue gun, glue, bridge, couple posts, alcohol for removing glue residue, etc). Down side is that it takes some time (clean, glue, wait to cool, pull, repeat).

 

Ladies and Gennamin:

We're trying to deal with this problem as if there was some Store-bought Gizmo, or some Black Magic ... Hoo-do Voodoo way that damage to the Fuel Tank is going to get miraculously un-wrecked.

Ain't going to happen.

Referring to the damaged area of this fine member's Bike as a "Dent" ... is akin to referring to The Grand Canyon as a Gully.

What else can you do?
Those of us who walked this Earth with Brylcremed Flat-Top Haircuts, Keds, Lucky's, Zenith Transistor Radio's, speaking to Operator's to call home from pay-phones and witnessed the birth of Rock-'n-roll, ... offer this solution.

Good Old Fashioned Sliding Hammer Dent Puller.
Study the damage and make as few screw holes as possible
Pull-out the damage.
Grind the whole area down to bare metal.
Dress the screw holes nice and flat.
Get a bunch of Penny's --> Real Copper --> Before 1982
Sand the Penny until the President's face disappears and it shines like new.
Sweat the Penny's over the screw holes.
Sand and hammer close enough for Government Work.
Bondo ... sand ... Bondo ... sand ... Bondo ... sand.
Shake can.
Flat Black.
Change shirt.
Comb hair.
Ride!

 

dont let the government hear you defacing currency its a crime lol dont worry i wont tell but thats the only way to fix it