I have just been given 5 fans from pc's, could have got loads as they were being skipped at work, and I was wondering if I could use them to add to some arc units I have that currently have no fans fitted. They are rated DC 12V 0.35A?
To be honest a fan that size wouldn't make any noticeable difference. At the very least I would use a 4 inch Planette fan or similar, even the blower out of a combi boiler or fan oven.
How big are they 80-100mm ?
If they are big enough to put out 100cfm or so, it might be worth the trouble.
One of these in 12vdc will run one of them easily .: http://www.allelectronics.com/make-.../EURO-230V-WALL-TRANSFORMER-6V-700MA/-/1.html
An AC fan would be the easiest and some of the welders have extra connectors on the back of the power switch to hook a fan.
Robert