Okay, I've watched the video on removing rust by electrolysis. I am the world's #1 skeptic when it comes to this stuff but NOW I am a believer!

Here's my proof
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The pics of a rotor before I dropped it in the tank.

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The pics after a 24 hour soak. The rotor is sitting next to it's mate. Same rotors, same storage place. The rectangular patterns on the rusty rotor are from the bottom of the milk crate they were stored in.

The "clean" rotor looked pretty good after only about three hours but it was dark in the workshop and the flash made for some weird pictures. I tossed the rotor back into the tank and took pictures the next afternoon.

I don't know what the darkened areas are but they clean off with just a quick swipe of a wire brush. Some impurities in the metal or grease migrating toward the positive terminal?

One tip is to thoroughly CLEAN the parts of any grease. You don't need to knock the rust off but grease seems to slowly migrate to the side closest to the positive lead and doesn't leave the metal object which is essentially the negative terminal.

40 ML's of sodium carbonate per gallon of tap water (distilled water might work better?). 2 amps of DC voltage (although bumping it up to 60 amps makes for some active bubbling!) at above 60 degrees F.

Wouldn't you know it! Now the rotors are all clean and I go to bolt them on. They're the wrong rotors for my W114. The mounting holes are wrong! Right lug bolt pattern but the wrong mounting holes, larger spacing and larger center cutout. W123 maybe?

Anybody need a set of NEW (13 mm thickness, never been installed) rotors for shipping cost?

Boy, that's impressive, Mike. I've never heard of that before, but it appears to work quite well. Thanks.

Okay, I've watched the video on removing rust by electrolysis. I am the world's #1 skeptic when it comes to this stuff but NOW I am a believer!
If you had pictures of the tank and setup it would make a very nice wikki DIY.







Thank you.

No set-up per se. A clear plastic tub apx. 2' X 2.5' X 6". Apx. 7 and one half gallon capacity. An old Sears battery charger and a collection of rebar rods used for the positive electrode.

The tub is actually an old "Rubbermaid" storage bin. You could use one of the cement mixing tubs available at any hardware/home improvement store. The clear is neat because you can see all the glop building up in the bottom.

No need for a DIY. The video covered the process.

On a different note, are the "pockets" available for the W114 subframe mounts"? The ones which are welded into the subframe cross member itself where the rubber part of the mount sits. They are just tacked in so it looks like they might be a separate item. It would be easier to replace them than to rebuild them as I have always done.

It's amazing the things you see when the parts are completely disassembled and out of the car. For instance, the lower control arms actually have drain channels designed to drain water out of the ball joint mounting area. These are usually all covered with road tar and closed.

OK, where's this video?

When I search on "rust electrolysis video" or "rust video" this is the only thread that comes up.

Inquiring minds want to know!

Sunny

Try this link.

http://www.metacafe.com/watch/456478/rust_removal_tip/

I'll pack the rotors up and ship them to you this week. I'm just guessing they fit the W123's. They don't fit W114's and the lug bolt patterns are the same.

I've sent you a PM with our address.

Wow! That video is something we call a "flat forehead moment." You know the moment when you whack yourself in the forehead and say, "Geez, I knew the science, why didn't I see how to do this?"

This is GREAT!!!! Thank you for letting the forum know about it.

Hunter, how about adding a link to the video under the DIY links?

Sunny

Yeah, the real pisser to the whole rust remover is I used to do the exact opposite to "electroplate" stuff back when I was in high school (in chemistry class when the teacher wasn't keeping a close enough eye on me). Removing the oxidation never even occurred to me. Doh!

It would be a great contribution to the Forum to add/include instructions for electroplating in this thread, since you know the "simple" way to do it.

There are folks here who want to do strange and interesting things to their parts.

CAR parts.

For everything else that implies, I'm not even going to GO there!;)

Thanks again for this great link and demo of your own experience.

Sunny

Errr, the "simple" form of electroplating involves pure silver or nickle dissolved in a nitric acid solution blended into a vat of mercury. Not exactly household chemicals and probably nothing I'd even consider doing now! Shucks, in high school, we were all immortal!:D

A VAT of mercury?!? Yikes!! Even my jeweler friends don't use that system! Yeah, not exactly household items....

Still, thanks so much. This is great, basic, immediately-useable info.

Sunny

Here is a nice pictorial: http://www.fordmuscle.com/forums/tech-exchange/467718-rust-removal-electrolysis.html

We used sheet metal for the anode. It was rolled to fit inside the bucket wall about an inch from the bottom. On a side note, we did this to some water pump pulleys and both of them cracked at the mounting holes after install. I'm not sure if the cleaning caused it or if it was just a coincidence.

It looks like further reading is warranted:

http://myweb.tiscali.co.uk/andyspatch/embrittlement.htm

http://www.practicalmachinist.com/vb/showthread.php?p=879394

http://www.htpaa.org.au/article-electro.php

Quote:

Hydrogen Embrittlement of Steel - A Cautionary Note
Atoms of hydrogen absorbed by steel are known to enter the lattice of iron atoms and prevent the layers from sliding past each other easily. This causes the steel to become more brittle and liable to crack. The absorption of hydrogen by steel is a familiar problem in industry which arises during steel refining, heat treatment, acid pickling or electro-plating. It can also happen as a result of simple corrosion. The standard remedy is to bake the objects in ovens to drive out the absorbed hydrogen (200°C for four hours would be a typical regime in industry). The simple passage of time is also known to cause loss of hydrogen from steel. Hydrogen embrittlement may occur to some extent during electrolytic de-rusting. This may be a cause for concern with saws or other edge tools. It might be wise to wait a while before setting saw teeth after prolonged, electrolytic de-rusting. Alternatively, baking the tool in the oven for hour or so at about 150°C (300° F) should remove absorbed hydrogen. Note that this baking temperatures is low enough to leave the temper of most steels unaffected. Since hydrogen embrittlement is reversible, it should not cause too much anxiety. I believe that the advantages offered by electrolytic de-rusting justify wider experimentation by tool collectors. As more experience is gained clearer knowledge of its advantages and disadvantages will emerge.

Hmmm, seems to warrant a bit of caution. I've never run into the embrittlement problem but I am not exactly what you'd call "fast" when it comes to putting the parts back on. I usually de-rust one weekend and then re-install, paint, polish or whatever the following weekend. Living in AZ. and leaving the parts in the sun to dry (I've recorded concrete at the temp of 164 degrees in my workshop) all week probably allows the hydrogen atoms to escape.

I wouldn't think the electrolysys process would cause the hydrogen to enter the iron since it is breaking the bond formed between the hydrogen and oxygen atoms but stranger things have happened. A chemist/physicist I am not.

Useful caveat and I'll be sure to advise on it.

Here is another really nice pictorial. It even has samples of different methods. http://www.globalsoftware-inc.com/coolerman/fj40/rustremoval.htm

I do not, however, see enough discussions of hydrogen embrittlement. That is particularly important when processing leaf springs and steering linkage!!!