I've been doing EDR (electrolytic derusting) for a few weeks now. Today I went
to the legendary Midway Swap Meet for the last time, as this place which has
been open since the demise of the once-ubiquitous drive-in theaters, is closing
for good, to be replaced by a (shudder) Lowe's. There were lots of people at the
swap meet and I found a nice DC ammeter for a real nice price. I got home and
headed down to the bucket where I'm EDR'ing my way through six old Ridgid pipe
threading dies. I wired in the ammeter and discovered I wasn't running nearly
enough current, only about 0.7 amps. I remembered the conventional wisdom which
was to move the electrodes closer to the workpiece until the amperage was about
right. I tried that. You know, it just didn't work for me. I didn't find much
variation at all in actual amperage as I varied the electrode distance. Then I
tried adding more washing soda. As I'd sort of expected, the current went right
up. At a tad over 2 amps it's sizzling right nice now.

So my question is, to the person or persons who wrote that if the amperage is
too low, vary the distance, are you *sure* this worked for you? I am a total
believer in experimental science, and the only procedure that is believable is
one that's reproducible.

Grant

Grant Erwin writes:

So my question is, to the person or persons who wrote that if the
amperage is too low, vary the distance, are you *sure* this worked for
you? I am a total believer in experimental science, and the only
procedure that is believable is one that's reproducible.


Crank up the voltage. If your power supply isn't adjustable or can't
handle the current, then upgrade the power supply.

Generally you should be pumping enough current thru the water to make it
warm and even hot, which generally means 10 amps or more. Once you get
that much power going in you'll probably find that distance to the
electrode doesn't matter very much.

Gregm

Hi Grant,

I can't offer you any help whatsoever. I was hoping you can direct me to a
source of information on how the process of EDR works and how to set up my
own system.

Thanks.

Joe..

"Grant Erwin" wrote in message
...
I've been doing EDR (electrolytic derusting) for a few weeks now. Today I
went to the legendary Midway Swap Meet for the last time, as this place
which has been open since the demise of the once-ubiquitous drive-in
theaters, is closing for good, to be replaced by a (shudder) Lowe's. There
were lots of people at the swap meet and I found a nice DC ammeter for a
real nice price. I got home and headed down to the bucket where I'm
EDR'ing my way through six old Ridgid pipe threading dies. I wired in the
ammeter and discovered I wasn't running nearly enough current, only about
0.7 amps. I remembered the conventional wisdom which was to move the
electrodes closer to the workpiece until the amperage was about right. I
tried that. You know, it just didn't work for me. I didn't find much
variation at all in actual amperage as I varied the electrode distance.
Then I tried adding more washing soda. As I'd sort of expected, the
current went right up. At a tad over 2 amps it's sizzling right nice now.

So my question is, to the person or persons who wrote that if the amperage
is too low, vary the distance, are you *sure* this worked for you? I am a
total believer in experimental science, and the only procedure that is
believable is one that's reproducible.

Grant

"Grant Erwin" wrote in message
...
I've been doing EDR (electrolytic derusting) for a few weeks now. Today I
went to the legendary Midway Swap Meet for the last time, as this place
which has been open since the demise of the once-ubiquitous drive-in
theaters, is closing for good, to be replaced by a (shudder) Lowe's. There
were lots of people at the swap meet and I found a nice DC ammeter for a
real nice price. I got home and headed down to the bucket where I'm
EDR'ing my way through six old Ridgid pipe threading dies. I wired in the
ammeter and discovered I wasn't running nearly enough current, only about
0.7 amps. I remembered the conventional wisdom which was to move the
electrodes closer to the workpiece until the amperage was about right. I
tried that. You know, it just didn't work for me. I didn't find much
variation at all in actual amperage as I varied the electrode distance.
Then I tried adding more washing soda. As I'd sort of expected, the
current went right up. At a tad over 2 amps it's sizzling right nice now.

So my question is, to the person or persons who wrote that if the amperage
is too low, vary the distance, are you *sure* this worked for you? I am a
total believer in experimental science, and the only procedure that is
believable is one that's reproducible.

Grant

Increasing the washing soda is what worked for me, until I got about 7 amps.

On Sat, 11 Jun 2005 21:37:56 -0700, Grant Erwin
wrote:

So my question is, to the person or persons who wrote that if the amperage is
too low, vary the distance, are you *sure* this worked for you? I am a total
believer in experimental science, and the only procedure that is believable is
one that's reproducible.

Athough I do more electrolytic "rusting" than "derusting," the same
rules apply.

You can increase the current (and speed of rusting/derusting) several
different ways:
1. Increase the voltage
2. Decrease the distance between the anode(s) and cathode(s)
3. Improve the quality of the electrolyte

Now that you have a meter for measuring, try it yourself. Set up your
system with pure, clean water. Turn it on. Note the current. Now
dump in your washing soda (I use baking soda). You'll be shocked by
what you see.

You can do similar experiments by varying the distance between the
electrodes. Just be careful not to get them too close unless you have
some kind of current limiting circuit.

Here's my setup if you need ideas:
http://engines.rustyiron.com/electrolysis

Rob



=-=-=-=-=-=-=-=-=
Rob Skinner
La Habra, California
www.rustyiron.com

On Sun, 12 Jun 2005 08:43:36 -0400, "JB"
wrote:

Hi Grant,

I can't offer you any help whatsoever. I was hoping you can direct me to a
source of information on how the process of EDR works and how to set up my
own system.

Thanks.

Joe..

You can download an eight page writeup from this site:

http://users.moscow.com/oiseming/rustdemo/rustdemo.htm

Orrin

On Sun, 12 Jun 2005 10:30:50 -0700, Rob Skinner
wrote:

On Sat, 11 Jun 2005 21:37:56 -0700, Grant Erwin
wrote:

So my question is, to the person or persons who wrote that if the amperage is
too low, vary the distance, are you *sure* this worked for you? I am a total
believer in experimental science, and the only procedure that is believable is
one that's reproducible.

Athough I do more electrolytic "rusting" than "derusting," the same
rules apply.

You can increase the current (and speed of rusting/derusting) several
different ways:
1. Increase the voltage
2. Decrease the distance between the anode(s) and cathode(s)
3. Improve the quality of the electrolyte

Now that you have a meter for measuring, try it yourself. Set up your
system with pure, clean water. Turn it on. Note the current. Now
dump in your washing soda (I use baking soda). You'll be shocked by
what you see.

You can do similar experiments by varying the distance between the
electrodes. Just be careful not to get them too close unless you have
some kind of current limiting circuit.

Here's my setup if you need ideas:
http://engines.rustyiron.com/electrolysis

Rob


If the "electrolyte" is not strong enough, varying distance won't do
much. If too strong, likewize. With the right mixture you would be
able to see the current change with distance.


=-=-=-=-=-=-=-=-=
Rob Skinner
La Habra, California
www.rustyiron.com