Gas tank weld - small pin hole

[Andrew Vanis]

I have this pin hole. thinking of spot welding it. any considerations other than flush the gas out beforehand (that step was already done, liquid leaking here is evapo-rust not gasoline)



history of this rust pinhole here - http://www.thegsresources.com/_forum...2&postcount=15

[tkent02]

When I have poked around pinholes like these, there have usually been 10 - 20 other holes just waiting to open up.

[chuck hahn]

This was a hole about 1/8 wide and 1 inch long. I broke off the rusted edges and got to solid metal. Then I started spot welding around the edges goingb spot next to spot till I had circled my way to the center.

This built up a good base to lay a little silver solder onto. Next I ground it down and smoothed with a MILL SMOOTH file.

Once satisfied with the shape and it being a good base, I redid the silver solder to be sure all pin holes were filled. Then as a filler to sand on and get the corner reconstructed, I use some JB weld.

Once all that was done, the tamk liner went in and it was shipped to Larry for paint.. Here is the repair and them painted tank


My repair job...everything you see in that darkest area on the lower seam and back corner is the HOLE(S) that I repaired. So yes it can be done with some skill and patience.




The painted tank..totally unnoticble repair....click on picture to view larger images.

[chuck hahn]

HINT....Do a few spots side by side and let the tank cool. This keeps the thin metal from getting too hot from rushing the job and melting away.

Zap..wait a seoncd..zap..wait a second..zap..then let it cool a few minutes. The restart the process and ever so slowly work your way around the hole till you've built up some thicker spot welds. Now you can start to do it a little faster..but still stop and allow it to cool down to prevent melt offs.

Do some more and so on.

[Andrew Vanis]

HINT....Do a few spots side by side and let the tank cool. This keeps the thin metal from getting too hot from rushing the job and melting away.

should have double checked this thread before plugging in the welder. I now have a dime sized hole

[chuck hahn]

OK...so shake out the slag that has fallen in and start around the edges again..this time a few quick zaps. By quick in mean hit the trigger and just make it spark a dot on. Let it cool a second and do another right next to the first. Youll get your own "feel" for how quick and how long to wait between zaps real quick.

'
That or take it to a shop and have them braze in a patch to cover it. Looks like its on the bottom anyway and wont be seen. Be sure to tell them the metal is only about 20/1000ths thick.

[Nessism]

For a dime sized hole I'd make a patch. Don't try to fill something that big with weld alone.

[Andrew Vanis]

braze in a patch to cover it...... the metal is only about 20/1000ths thick.

I can braze (i think) it I go that direction, anything to keep in mind other than clean, flux, and rod?

no wonder it just evaporated even on the lowest setting.

[chuck hahn]

Do some testing on where the rod melts as to the flame..then use that setting. A torch can just as easily pop a hole as the welder can. If your in doubt, have a shop braze a patch over it for you.

[rustybronco]

IF the metal is thick enough to support tapering the edge of the hole, then that's what I would do. Enlarge the hole and bevel its edge in order to fit an easily handled equally beveled patch. Use a die grinder or a rat tail file the bevel the hole and bevel the edge of the patch by filing it's edge as needed to best fit the hole, then braze the patch in place.

Repairing the burn through by this method will allow for the minimum amount of filler necessary to hide the repair. Plus it's considered better workmanship than just slapping a patch over the rusted area, bashing it down and hitting it with a coat of filler.

http://thegsresources.com/_forum/showpost.php?p=1666489&postcount=535

http://i32.photobucket.com/albums/d44/rustybronco/PICT3523.jpg