Alloy Tank Repair

Hi all. I have an '82 WR250 which will be stripped down this summer and 'refurbished' so to speak. Just wondering how dents are removed without cutting the tank open? If an 'opening' is required, what precautions do you suggest.
Thanks, DD

A good TIG welder can weld pins to the tank and the pins are pulled out to remove the tank. Sand smooth and buff after. Another option is air pressure but you can blow the seams if you're not careful.

Auto body shops have specialists they call to remove dents. They show up with their specialty tools. If the auto body shop I have some inside information about calls in a subcontractor that might indicate similar solution. I have not had much success in cutting a hole in an exhaust to get dents out.

With the dents in pipes I read about putting water in the pipe and letting it freeze. I would think that you need to position the pipe so that one area freezes.

The dents in gas tanks someone cut the tank apart on the seams then removed the dents and TIG welded it back together. I need some dents removed in a few gas tanks.

I wonder if we use air pressure and lightly heat the dented area will it pop out. Very little heat.

your tank is very bad ?
yes ?? look picture is
only possible !

is possible
by tools garage
only small dents !

ive seen the water freeze remove a good sized knee dint in a ts 125 tank.

Air pressure and heat will work. That's the method used for exhaust pipe repair. With an alloy tank propane or MAP gas should be enough without overheating the metal. The metal is thin on a tank so obviously you have to be careful not to melt the aluminum.

Nope! Claude correct. You cut an alloy tank apart. Remove dents, weld back up.

Now a steel tank as long as not creased, you fill tunnel with cement, strap outsides, and can heat and use water and ice to shrink dent. Sometimes you have to cut them as well.

Air pressure! Good way to for it to blow, tear open and cut your fingers off!

Pipes are different story cause they are heavier gauged steel.

Here is steel tank that was smashed beyond recognition.
I cut side out, straightened it with heat, body hammers, filed it and sanded it.
Then you tig weld it back up, using low heat and wet rag so doesn't warp.
Pressure test it with soapy water, send to chromers and your done.

Claude and darty are correct. Do not use air on gas tanks, you will ruin it. I've seen a couple people had tried it on. Not pretty.

Thanks for the responses chaps, what was best for cutting them open, I have an air drill with a cutting wheel. Any advice to the bloke who does the welding? Regards, DD

been there, done that
ruined a perfectly good tank with a small ding back in 72 or 73
NEVER USE AIR

advice? make sure its totally clean of gas before welding

I can attest to that as I kept applying more pressure because the dent was not pushing up and everywhere else became bloated and the top of the tunnel caved in closing the tunnel gap. This was on the minorly dented TT500 aluminum tank.

Thank to listening to a knowing friend, I created a much bigger chore than I started with. Chapter 2 soon. I got some good advice from Dartyppty as he had done the same at an earlier project. So this is an example of how we learn from our mistakes and become driven to find out how to recover and move on to our objectives. And why we try to warn when we see you trod down the same path of advice that we get from those who do not see the consequences.

Wise words oh Jimspac -san. Definitly a precise job if you use heat and air pressure. Aluminum is hard to heat properly. I shouldn't have suggested it.

What do you reckon about this one, require 'opening up' to repair?
Thanks,

Do not try to freeze it with water, the water will split the tank at the welded seams. I saw somewhere a video of a guy who used blocks of wood with a long C clamp to pop out dents, it worked great. I'll see if I can find it again.

Yup, I didnt do that on a tank but I did it on a pipe. The water will expand at the weakest point, which is rarely where the dent is.