anyone done this?

thinking of giving it a go - drill a 10 mm hole so that is makes a 5 mm hole (drill has conical end) in the lower piece, then apply torch, hopefully get it up to temp then put in filler rod.

good/bad plan?

You may find that, having thinned the lower sheet with the drill tip, it will be prone to blowing through.
10mm hole in top piece only, weld around the hole edge neatly, & optionally fill the centre last of all - done this before successfully. Deburr the hole first...

forgot to say, top piece is 3 mm and lower is 15 mm dia so no chance of blow through ... probably won't be able to get enough heat in to melt anything but was wondering if what I had in mind was sensible

The most difficult part is adding the filler wire.

you will struggle to get a good Tig plug weld through a 5mm hole in a piece of 3mm. I would just drill it out complately to 10mm. i dont know how far out you protrude your tugsten, but when im tiggin normally, i sharpen my point to about 4mm long, and just have that much protruding from the ceramic shroud. but if i was going to be plug wolding holes like that i would probarbly protrude the tungsten out about 7mm to make sure i can get the heat into the bottom corner a bit easier

What's wrong with the usual MIG method?

quote:

---

Originally posted by DIY Si
What's wrong with the usual MIG method?

---