Posted by David Sherman on Monday, July 04, 2005 at 8:15PM :
In Reply to: Re: Should work fine posted by Mike (Montreal, Quebec) on Monday, July 04, 2005 at 7:26PM :
I suspect that for de-rusting, a constant-current source would be better than a constant-voltage source because it would keep pushing the same amount of current through the work regardless of how clean or dirty the work, the scrap metal, and the solution were. A simple battery charger tends to approximate a constant-voltage source, whereas a welder is more of a constant-current source (that's what stabilizes the arc). It would be interesting to do some experiments and see what works the best. If I am right that a constant-current supply would do a better job quicker and with less cleaning of the scrap iron, it might be worthwhile to build an optimized de-rusting power supply rather than try to jerry-rig battery chargers or other field expedients.