Buy copper... at least 3/16" thick
chop a piece to make fit
so rules:
1) the gap can be as wide as you wish it to be.... Milner, don't listen because this really is siliconing with steel
2) the back must be clean too
3) great is clamp the copper to the bottom of the weld - the tighter the better. this also means deburr the hole
4) you can also use aluminum bar
so here's the deal - as long as the copper or aluminum is clean, you can literally lay the bead inbetween the edges using a tack method. there's another way, but first to illustrate this
notice the hole is actually wider then the 3/16" copper?
I can't clamp here - which leads to varying clever solutions... in this case, the frame is below the joint - so I dig out a bunch of things I think I can jam in the hole
none are right
but found something
see the tacks? how they're not falling through?
the other benefit is the copper or aluminum works as a heat sink
nice, smooth weld... we'll talk about the upper one next
Did you know that you can use welding rod WITH a mig? say you find yourself chasing a hole because the rust went further than you thought it would? you can't back it because it's enclosed, what to do?
while I advise using silicone bronze wire, you can also use ER70s (standard steel)
yep, you feed it just like you do when tigging or you tack the ends across the hole... the trick/goal here is to add enough metal that when you weld between the stitches, it simply looks like a wide weld.... never do this for structure but bodywork? especially floorboards. the thing here is it doesn't add so much heat as any other method - so you run less chance of warping. If the part is extra rusty, though, silicone bronze is your friend
in other news... stupid steering columns, I went to start this yesterday and the ignition switch seemed disconnected from the starting rod.... I'm sure the bottle opener looking part snapped... buy new? would be easier. Borrow out of another column? sure but there is another solution - they make rebuild kits for these because of the penchant of people stealing this trucks by breaking the column. I may add a permanent fix to that to reduce that risk....
to be continued