After getting a message from HenryF here on the site asking about the process of pulling a dent out and writing it all out for him I decided to make this into a how to with pictures so others may benifit from the same advice.
if you live in an area that is built up you should be able to go to just about any body shop and have them weld the pins they use pulling the dents on your car they are the same ones used to pull the ones on your tank, If you can not find someone here is a basic how to on how to pull them yourself. If you can find someone willing to do this instead of doing it yourself I would recommend it, For those guys who want to do all there own work here is some helpfull hints on performing the task
Here are some of the tools you will need.
Spot welding gun, pins, slide hammer. Ball peen hammer, Punch. Board Sander. Air nozzle, soapy water in a spray bottle, not shown air compressor and regulator and wire feed welder
There are some draw backs to finding someone to do it, their concerns will be that the tank will blow up,
They Are Very Real!!, make sure the tank is dried out, have them run some compressed air through the tank so no fumes can build up. This is as important for you as it is for someone who may be working on a tank for the first time. I often let a tank sit with air blowing through it for 20 minutes just to be safe.
This is a picture of a friend of mine and fellow custom painter, he cut some corners and paid the price, over the years I have blown up two tanks both times from rushing, This can be done safely but you have to treat what your doing with some measure of common sense.
You can be seriously hurt or killed doing this.
It takes many pins to pull a dent, the average baseball size dent it is not un-common for it to take 8 to ten pulls to get it to move, use the slid hammer only five or six times at the most to pull on the tank, then cut it off and weld another. I often start on the outside edge and move in when pulling.
Also the concern for pulling the pin through and leaving a hole in the tank so that it has to be welded shut should be considered, it does not happen a lot but it does happen and you are more likely to do so while figuring out how hard you can pull on the tank, It is important to keep the tank as solid as possible, the dent will pull easier and you will be less likely to put a hole in it. Once you have welded on the tank to fill any holes you will have to pressurize the tank to make sure there are no leaks, not that tough just block off the openings and put about 10 psi of air in to the bottom opening and then check with soapy water for any bubbles. The best rule of thumb is to use more pins less pulls, it will safe you the trouble of trying to weld up the hole you just made
Next is the hard part...High spots on the tank are what make repairing them difficult. if you imagine a crater from a bomb the hole is there and around the hole is the edges which are now higher then they were originally, Once you have pulled the dent you will have to hammer down the edges so that you can do body work, The best way to find the high spots is to use a flat sanding board and go over the area that was pulled and see what shiny spots show up. Take a hammer and a punch and lower them maybe a 1/8 inch or more. Put on your first coat of mud and then repeat the process. While this all sounds very simple, high spots in the tank will make it impossible for you to get your body work to look right. Often times it is just one small high spot that will give you tons of grief
This high spots are shown in this picture, you can see the shiny spots after going over it with a board sander
Once I am happy with the body work I then use a polyester primer to fill in any minor imperfections, it normally takes about 5 coats of primer, I sand inbetween the 4 and 5 coat with 120 grit and then 220 and then prime again
The finished tank
If your intersted in having us pull the dents and do the body work it is not that expensive, just let me know when you send me a note so that I can give you the board discount..Bob
