convert an ac welder into a dc one

Hi l'd to know if it is possible to convert a AC welder into an Dc one
simply
using an Hi-power diode bridge.

thak you in advance for your reply

Lore

 

Possible? Yes. Practical? Ehhhh... debatable.

The problem is finding diodes that are beefy eough to handle the current
without letting all the smoke out of 'em.

 

A diode bridge is no problem, but the result is not a practical DC
welder. You need to add a hulking big inductor downstream of the
bridge, to stabilize the arc, or you just produce a lot of splatter.

A couple of these duals or 4 singles mounted on heat sinks make a
passable diode bridge:
http://rocky.digikey.com/WebLib/InternationalRectifier/Web Data/IRKD,E,J,C 91 SERIES.pdf

Big diodes are often for sale on EBAY, also. e.g.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3807560657&category=7287
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3806442995&category=36332
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3807594327&category=36332