[sdiy] Aluminium Solder

[metasonix]

> One of the ideas is that so I can flush mount 3mm screws (or threads)
> into the front panel plates of 19" racks. So you can't see them from the
> panel side but allows you to bolt a front panel board to it as a sub
> panel etc. 

It's called a press-in, or PEM fastener. Available in screw or nut form. 
Yes, they do make "blind stud" or concealed-head stud types 
(which is what you want).

http://www.pemnet.com/comp_lit_files/

You can press it in place with a hand swaging press. 
If it's going into an aluminum panel, it's easy. 
Steel requires more pressure.

> I could dril a hole big enough for the nut to slip through and then
> solder it in place.

I don't recommend aluminum solder for this--not very strong.
It also requires a lot of heat if the piece is physically large--
might require a butane torch. Most soldering irons don't get hot
enough for aluminum soldering.

> saving what I can to buy a small second hand welder of some kind that
> can do this stuff. Perhaps I'll find one on eBay..... Maybe not...

Yes, a heliarc type welder is the best approach.
But if all you want is a captive fastener, the press-in
types are cheap--and no, you don't need compressed air
to put them into aluminum.


-- 

Eric Barbour
Owner, METASONIX (www.metasonix.com)
Senior Editor, Vacuum Tube Valley magazine