Electrolysis or Elbow Grease?

Mark Kosmowski said:

Ken:

I had the chance to play with Griz's setup when he helped me restore those hand planes earlier.

My question was about whether or not electrolysis is a line of sight phenomenon. I didn't think it was. I did a little research to convince myself that it isn't and found this interesting electrochemistry site: http://www.chem1.com/acad/webtext/elchem/

In the electrolysis section there is a picture showing that most ion (charge) movement in solution is due to diffusion, essentially a random motion. So it shouldn't matter where the rust is relative to the other electrode - if the rust is in solution it should eventually get electrolytically removed.

I've been learning more chemistry from my hobbies lately than from my career as an analytical chemist - it's fun.

Click to expand...

What I can say to that is many of the sites I used as reference when I set my tank up had indicated that it was line of site and mentioned current flows, which are electron flows and they like to take the path of least resistance between where they're goin and where they're comin from. That would indicate a straight line through the solution. There were also references to using iron or steel tubs as the anode and filling the tub with your solution, suspending the item to be derusted with contacting the tub/anode in order to get cylindrical coverage of electron flows.

The couple of saws I derusted before I nearly ruined one from hydrogen hardening, seemed to want to be flipped partway through the process in order to get both faces done. As well, I found I still had rust often times inside of small threaded holes in hand plane bodies after spending a day or so in the tank. This evidence sorta backed up what I had read.

Jerry:

Fluid dynamics is tricky - maybe there's something else going on that makes both of us right - I wasn't trying to pick a fight, but was just trying to learn if my understanding was wrong.

If you still have some of your sites available I'd love to read them for myself.

Happy tool usage!

Went looking through my links and found several to be dead now, but
this one is still up and gives an explanation from the perspective of an electrochemist. This was the site where I got the electron flow idea and made the presumption that electrons flowing in an electrolytic solution would want to behave as they do in a circuit, taking the path of least resistance. I still don't "know" if that is the case, and it might even vary, as far as I know, depending on the solution through which it is passed.

This link mentions "almost line of sight" of the process as being the reason to use several anodes spaced around the container. That is only one of a number I found previously.

I didn't think you were wanting to pick a fight, this forum not being like some others where folks seem to look for stuff to disagree about. I've always been someone wanting to go beyond the "how to" and into the "why" of things, so I understand where you're coming from. One of the things I love about the internet (IMO it used to be better when the bulk of stuff on it was on University sites) is that I can look for the "why" of almost anything and find info. Of course, ya gotta separate the wheat from the chaff, but that's okay, too.

One thing I have noticed in discussions of electrolysis is that folks seem to get different results. Not so much in the reduction of the rust, but in the appearence of the metal after the cleanup once the electrolysis has been done. Some seem able to get nearly new appearing shiny metal with little effort, while others seem only able to end up with a greyish cast to the metal unless they actually remove the surface metal using a wire wheel or such. I don't think it is likely the condition of the piece prior to the efforts as is seems consistent by the person making the effort. I'm in the second group. This grey color is about the same as is left behind when one cleans surface rust off of iron or steel and then applies some oil to "kill" the rust.

Since I discovered, citric acid, I'm not using elbow grease anymore, or at least no as much as before.
As already said it is environementaly friendly, not dangerous, you can use it with bare hands etc. etc.

And it saves you a lot of effort. The measures are not critical, it depends on how long you leave the piece submerged in it. If it is too much it becomes almost black similar to blueing, and I guess that it will behave like that.

If you check often you can withdraw the piece at the stage you want.
Check the some pics of my 607 bedrock restauration/cleaning.