Is it OK to weld closed some drilled holes in my 1960's truck frame?

[sixdogs]

I believe welding will actually weaken the frame. At least do some research before wading in.

That's what I'm trying to do since there are some pretty book smart and street smart people here. The frame has to be soft steel since I drilled it with a hand drill. You wouldn't think that would be hardened in any way considering the loads of 1967. It's not a modern frame.

My inclination when I started was to weld the holes shut because I thought that would make them stronger. Now my thoughts are to leave well enough alone and call it goodd. Still thinking.

 

[jaxs]

Not exactly the same subject but I believe it demonstrate's that metal undergo's change when heated then cooled. Knife makers often use old files and rasps which will shatter when struck with hammer. The metal is heated then cooled under controlled conditions which render metal pliable. After hammering into desired shape,it is again heated and cooled under controlled conditions to make it hard.

 

[Sodo]

In the pickup class of trucks, 35K psi is more common.

Agreed, a regular pickup frame is probably not high-strength steel. If it's mild steel (such as 35ksi) then welding up the holes WON'T weaken it. You said it drilled easy, that's usually a good test, but maybe you had a wicked drill bit and didn't know it?

Do a spark test on it just to be sure. Find a scrap of mild steel and compare the sparks to those from grinding the truck frame. If it's mild steel you can do whatever you want. Mild steel doesn't heat-treat and consequently doesn't embrittle either. Grind a tool or touch one of the leaf springs and you'll see what high-strength steel sparks look like.

If the sparks look the same as mild steel......I'd get one of those copper paddle welding tools from Harbor Freight. I can't and can't find it on their website, but they have it in the store and it's cheap. It's specifically for welding up holes. You just cover the backside and weld in a circle. I'd round-file the hole first so it's all bright shiny clean and the weld starts nicely. Here's the plug weld tool on Amazon http://a.co/d/dYOB0Ga or just a copper plate clamped on http://a.co/d/1ay2qUG

And then, what are you going to use this truck for? It's 51 years old. Are you gonna load it to max GVWR and drive it on uneven roads at max GVW,,,, flex the frame a lot? If just restoring it do what you want so you're happy with it..