removing dent from tank?

[davomoto]

I had a similar looking dent in a CB77 tank. My body man friend found the exact center. hit it with a spitznagel, then an easy tug with a slide hammer, and it popped right out.

Davo

http://www.dentfix.com/viewitem.asp?idp ... elding+Kit

[Snakeoil]

Davo,

I've pulled more than my share of dents on tanks, all with excellent success.

Regarding air pressure, you could try it, but use a bicycle pump. Plug the filler neck with an expandable plumbers rubber plug and put the air hose on the petcock. Then pump it up and see if it will pop. Would not take more than a couple of pounds if it is indeed poppable. Just put your hand on the good side of the tank on a flat area and you will feel it bulge. Then use that as your indication of when to stop pumping. But, all that said, I've never used air pressure to pull a dent on a tank.

The method I use is home grown. I was thinking of marketing it, but research told me that there are similar systems out there for sale. You might even be able to save the paint, depending how good a bite it has.

Make a tool that will fit in your slide hammer (assume you have one) as follows.

Take a large plain washer, maybe 1-1/2 in diameter. Drill 1/8" holes around it so that it looks more like a sink drain. Now weld it to a bolt that will screw into your slide hammer. This is the tool you will use.

Now, with a hot glue gun, melt hot glue onto the tank's dented surface. Look for the area that appears to be the deepest as that is the center of the dent. It may not be in the actual center, but it is where you want to start. Put a generous amount of hot glue on your newly made tool, also. The holes you drilled with help the tool to grip the glue.

You also need a heat gun for this process. A hair dryer will probably work, but takes too long for me. With the heat gun, heat the glue on the tool and the glue on the tank and then glue the tool to the tank. Once it cools, pull the dent with the slide hammer.

Tips
First few tries will probably result in the glue releasing from the tank quickly. That's normal so don't get frustrated. Repeat the heat and stick process and eventually it will hold well and pull the dent.

Have an air hose handy to cool the glue quickly. The hardest part is holding the slide hammer in place while the glue hardens. So, I have the heat gun and the air hose within my reach and I heat, stick and then cool with the air hose and then pull.

What you will find is that the glue will release as the dent pulls out to where the material was originally before being dented. I pulled dents on a very ugly CL160 tank and told the buyer that I had pulled the dents. He could not believe the tank had ever been dented.

Don't over-pull and be patient. As you pull, you will find that you may have a new low spot develop. Move to that spot. Idea is to pull the dented area evenly.

What I've found is that the thicker (directly proportional to age) the tank material, the more even the dent pulls. I pulled dents out of my SV650 roadracer twice and that tank is so thin I had to keep moving the tool to get an even and uniform pull.

This works just like a stud gun, but without the expense of the gun, the risk of piercing the tank or the need to purge out all the fumes.

Be careful with the heat gun if you want to save the paint. I know it is hard to believe, but I have pulled dents with the paint between the glue and the metal. Yours looks like a good candidate for that.

The hard part is getting the damn glue off when you are done. If you don't care about the paint, solvent works. If you want to keep the paint, you can scrap with plastic or wood scrapers or use ice to make it very hard and try to chip it off. Goof-off, which removes other sticky stuff is another possibility to get the final residue off.

Good luck,
Rob

[jensen]

Hi,

Thanks, I'll try this method,

Jensen

[jleewebb]

thanks, Rob, this is cool...going in my archive...

pardon my density...when you say pull with the slide hammer are we pulling smoothly or banging?

thanks for sharing --Lee

[Snakeoil]

A slide hammer is a weight on a steel rod. You attach it to something and then slide the weight (hammer) up the rod until it hits the stop at the end. It transfers its energy to the rod, which is attached to what you want to pull and it moves outward a bit. Standard tool for pulling threaded dowel pins on big machinery. Used a lot in body shops often by welding a stud to the body or even drilling a hole so you can fasten the rod of the slide hammer and then pull by banging the weight up against the stop on the rod.

You can buy one cheap at Harbor Freight. You can even make one with a large chuck of steel bar with a hole thru the middle and a piece of 1/2" steel rod. Drill and tap on end or weld a nut on it and weld a piece of plate or large washer on the other end as the stop.

Wear leather gloves because it is easy to pinch your skin between the weight and the stop and it will bite a chuck right out of your hand. Most commercial slide hammers are made to protect you from that.

I want to reiterate here that the glue will pull off and you will have to repeat the heating and gluing process over and over as you pull the dent. For Davo's, I think he'll be done in a few minutes. But I spent hours pulling the dents on my SV tank that was bashed in on both sides when the steering stop sheared off, on top from who knows what and towards the back from a knee. I had to do this when I bought it because the PO had run off the road in the dark when he missed a turn and later when I wadded it at Pocono IR. It actually came out better the second time around and I used even less bondo for the stuff I could not pull or smooth out than I did the first time.

And one more thing. If you don't have a hot glue gun, don't go buy one. Just buy the glue sticks and use the heat gun to melt the glue onto the tool. This is not one of those gluing jobs where neatness counts.

I've attached before and after pics of my SV tank. This was the first time around. Note that I did scuff up the paint because I wanted the glue to bite better and was repainting anyway. Plus this was the first time I ever tried doing this. Notice that the paint remained and only the S decal pulled off.

Dreamed up the idea one night and figured it could not hurt to try. The smaller dents are harder to pull because you cannot make a small tool and still have enough surface area for the glue to hold well enough to pull. In such a case you could braze a nail to the dent and pull using the slide hammer then simply remove the nail by reheating. In case it is not obvious, you braze the head of the nail to the tank. You can put a hook in the nail shank to grab with your slide hammer.

regards,
Rob

[conbs]

What Snakeoil has described is one of the methods that the PDR guys use. They have various sizes of little plastic pieces that they glue on the dent (w holes like he said to drill in the washer) Then they have an end that screws on their slide hammer with a hook that catches the top of the plastic piece. They put the glue on the tank and plastic piece at the same time. When it cools, they hook the slide hammer over the top of the plastic piece and pull out the dent. It ususally saves the paint, too; hence paintless dent removal. I bought some of these tools and watched some videos online showing how to use them, but I have not had the occassion to try them out yet.

Sometimes the glue comes loose and you just repeat. They say that the glue releases and comes off if you put rubbing alcohol on it and pick at it a little.

You might also think of buying one of those little bars that they advertise on TV for small dents. Some use hot glue and some use a suction cup. I think Harbor Freight sells those. They are pretty cheap, but might be made to work.

You also might think about putting a couple pounds of pressure in the tank and then trying one of these methods. It shouldn't take much.

One caveat: if the seam in the tank is bent, that may be what is holding the dent in. If that is the case, unless you unlock that damage first, you may have a hard time pulling the dent out without leaving some distortion still in the top of the tank.

[OldStan]

Results;

Started with the glue gun and slide hammer. I decided to try a puller, more gradual pressure. I glued the puller on about 5 times before I got it to pop out. Luckily the dent was in a spot I could bridge pretty well. The dent come out pretty well. There are three small dimpled areas that I have yet to work out, one of which is next to the seam so it probably won't come out. I've constructed an end for a small slide hammer but haven't had time to work on it much more. I may adapt it to the puller as well. Even if I can't do any better the spots can easily be filled as they aren't very deep.

I'm pleased with the results, thanks for the input everyone.

One thing I noticed was that on the painted surface the glue didn't seem to hold too well until I sanded it with 150 grit sandpaper and cleaned the residue off well. I heated the surface with a heat gun prior to putting on the glue, in warmer weather it probably wouldn't be necessary.