Well, I have a client that is having me build them a motorcycle and I ran into some problems on the tank today. I thought that since I was having to repair the tank that I would share a little and possibly help someone else out. First, let me apologize for the blury pics as everything was taken with my cell phone. The tank is an old banana wassel. I do not know if they repop these but even if one could be found it would need to have the tunnel modified for the frame that is being used. Here is a pic of what I started with, looks like a clean vintage tank.
I was cutting the edges off of the tank, to clean the look of the tank up, and stripping back the paint to prep it for TIG welding, when I found some bodo peaking out at me. So I decided to start stripping back into the tank to see how much was there.
Funny thing was that the filler did not go toward the back of the tank that far and it seemed to be concentrated on the front corner of the tank. The big questions I was wanting answered was how deep did it actually go. Well, I started to dig into the fun stuff and dig, and dig, then this little nasty thing revealed itself.
When I looked at this I knew that the tank shell would have to be seperated from the tunnel so I could get inside and metalwork out the cavernous dents. So after cutting the edges of the tank off with a cut off wheel and then grinding the edges down with a sanding disc this is what the tunnel removal looked like.
After getting the tunnel removed I got inside with one of my post dollies and started working out the dents with a body hammer. I worked the tank for an hour or so until I got it metalfinished close enough where it would only need a skim coat of body enhancer.
The client had a custom gooseneck frame made by Flyrite so the top tube was at a lower angle, more horizontal, than the usual frame. This meant that in order for the tank to sit properly on the frame a new tunnel would have to be made to allow the front of the tank to sit higher and look level with the top of the motor. So I grabbed a piece of spare tubing and some 16 gauge cold rolled sheetmetal. After taking a few measurements, and adding to them, I clamped the tubing on top of the sheetmetal so it could be folded over the tube. Remember when doing this that the tube will need to be lower than the centerline of the sheetmetal because the sheetmetal gets wrapped around the tube. Like so.
After that I set the new tunnel on the backbone of the frame and slid the tank over the tunnel where it looked level with the head of the motor. I marked the outline of the tank on the tunnel with a sharpie and took the new tunnel over to trim the excess material off with my electric shear, but some hand shears will work also. Instead of welding on tabs to mount the tank I left more material on the leading and trailing edge on the top of the new tunnel to mount the tank. This way the new tunnel is one piece with the mounts, which is made out of 16 gauge, and gives the tank more strength. Most tanks are made out of 18 gauge material so the 16 gauge is just some extra insurance. This is where I ended up at the end of the day.
Tomorrow I will make a filler piece on the english wheel, due to the compond curve on the front of the tank, then I will TIG weld everything in. I will also fill the bungs where the petcocks are now then move them to the rearmost part of the tank. This will solve the clearance problem with the petcocks and motor that exist at this time. I hope this has been useful and contributes to the board in a positive way. If others are interested I will take better photos tomorrow, left my camera at home, and update the progress on the tank.
How to Rehab a Tank
Linear Mode
