I think i want a spot welder

[Screwdriver]

Those are made from copper zirconium alloy which is the correct stuff for welding electrodes. You buy the rod stock, cut to length and drill and shape electrodes. On my welder the stock for the arms needs to be turned down on a lathe where the welder clamps it but it's a simple job so so shouldn't be too expensive. All materials available from JayMig welding supplies.

Tried to take a look at what's on offer but "You are not authorised to view this resource." Not only that, there's no easy to find link to enable a log in or request an account.

I'm modifying some strap clamps to fix bags to a large extractor.

Looks like stainless steel to me. 20mm x 0.5mm strapping. Takes the very briefest click possible on my spot welder and despite thoroughly cleaning with acetone, I get this interesting "splash".

Whatever it is, it is tough stuff. Possibly some sort of carbide. It is of course incredibly sharp and the fist time I "discovered" it with my thumb, the tips bent up into needle like shards. It is also surprisingly persistent. Rubbing it with a cloth seems to be the best way to worry it off by fatigue but again, it is surprisingly robust. I would expect a few wiggles and it would snap at the bend but it can take a dozen attempts. Craft knife also struggles to nip them off so it is both hard and "ductile" at the same time!

Anyone know what it is?