"Snag" wrote in message
...
RS at work wrote:
I finally tried electrolytic de-rusting and I like it. I tried it on
a sheet metal blower housing off a lawn mower and I was really
impressed with the results. The pitted areas of the metal were
blasted completely free of rust and the process removed most of the
paint as well.

The downside is that I now have a dead Harbor Freight battery
charger. I found a 24 V forklift battery charger that runs on 220 or
440 and will deliver 12.5/25 amps. the guy wants $20 so this might be
a good deal.

Is this a good candidate for making a dedicated power supply for an
electrolytic de-rusting set up?

I know that a cheapy little battery charger will work but I assume
that the forklift charger has much heavier internal components so it
should last.

I also understand that the power requirements to de-rust vary
depending on the surface area and the conductivity of the solution.
Would it be easy to tweak this charger to make it so I could dial in
an optimal setting?

Also, what sort of fuse or other safety should I be sure to build into
the supply?


Roger Shoaf

What you want and need on the output is a "PWM controller" . Stands for
Pulse Width Modulation . Google that for more info , but the net result is
current/voltage control . I use one to control the temp of my 'lectric
motorcycle gloves . They are also commonly used to control DC motor speed
. Kits can be had fairly cheap , mine was around $35 including case . You
can also find them on eBay ...
As far as fusing , I'd think you'll rarely draw more than rated amps ,
say fuse it for 15 with a 220 supply . I'd fuse it at the output of the
PWM though - unless your PWM is rated less than the supply's output spec ,
then I' d fuse the input .
--
Snag
Learning keeps
you young !

A linear adjustable current regulator is not difficult to build.

I think there's a research project in the PWM idea.
Does it work as well as continuous current?
Does it work better?
Is high voltage (current), low duty cycle an advantage?
A quick Google search didn't find any data.
Mikek