PDA

View Full Version : Rusty Kant Twist clamps



Glug
08-14-2016, 11:07 AM
I picked up four of them at a moving sale, for $10 (I probably could and should have gotten them for five, but I wasn't going to try and lowball a WWII Veteran).

They're older Enco's and kinda rusty. The rust won't impact their function but I hate rust. I'd guess they were zinc plated originally, or similar. I don't want to spend any time on this (why did I buy these again?). If they were C-clamps I could give them a quick going over on the wire wheel, but that would not work for the inner surfaces.

I suppose the least effort cleanup would be electrolysis. I haven't tried it before and this might be a perfect project to give it a try. I've heard stuff rusts really quick after removal, so what then? Hmm. Sounds like I should just oil them and put them in the 'useful rusty old tools' tote.

On another note, I just won a nice vibratory polisher at auction. Haven't picked it up yet. It might be just the thing for the smaller stuff that would fit in it - assuming the media doesn't beat up the threads.

Rosco-P
08-14-2016, 11:30 AM
Dry them in an oven after derusting, 250-350 degrees F, followed by a wipedown with phosphoric acid.

MichaelP
08-14-2016, 11:48 AM
An overnight soak in Evaporust will do the job.


P.S. Evaporust destroys surface blackening and may affect the remaining zinc plating, but since you're ready to remove it mechanically anyway, I see no problem.

Glug
08-14-2016, 01:44 PM
An overnight soak in Evaporust will do the job.


You're right. I don't know why I'd dismissed that earlier. Then, what to cover them with that won't just scratch off from rubbing in a drawer?

MichaelP
08-14-2016, 02:18 PM
If the humidity on your shop is under control (no rusting of other tools), there is no need to do anything additional. However, a touch of oil wouldn't hurt anyway.

If you want to be really fancy, you can parkerize the clamps: http://bbs.homeshopmachinist.net/threads/39446-Let-s-Parkerize-Something!

ed_h
08-15-2016, 10:22 AM
Evaporust won't hurt any remaining zinc plating. It's also superior to electrolysis for this kind of part.

Ed

lakeside53
08-15-2016, 10:49 AM
Yes, stay away from acids to conserve whatever zinc you have left. After Evaporust and wash/dry, spray with CRC 3-36. Dries well, not sticky, protects well. I squirt it on most of my stuff once a year.

studentjim
08-21-2016, 06:12 PM
I use cleaning vinegar on all rusty items. Cover the items with vinegar and let sit over night or longer if needed. Much cheaper than Evaporust, non toxic and can be used over again. Wash off with water, blow dry and spray with WD40.

jbacc
08-21-2016, 07:07 PM
I use cleaning vinegar on all rusty items. Cover the items with vinegar and let sit over night or longer if needed. Much cheaper than Evaporust, non toxic and can be used over again. Wash off with water, blow dry and spray with WD40.

I do the same, white vinegar...Works great.

Forrest Addy
08-21-2016, 07:19 PM
Yeah. Evaporust. I haven't used it yet but the videoed experiences of other have brought me around. Expensive though. The active ingredient is reputed to be a fairly common chemical, EDTA. You do have to help it along with some in-process scrubbing

https://en.wikipedia.org/wiki/Ethylenediaminetetraacetic_acid

which you can buy in quantity on line. This is unconfirmed info. Experiment on samples before you commit to irreplaceable parts.

Electrolysis is fine but it works kinda "line of sight" from the anode. It doesn't reach around corners to get the inner surfaces you mention whereas a soak in a chelate will..

ed_h
08-21-2016, 07:39 PM
Evaporust is widely rumored to be based on EDTA, but I haven't seen good proof of it. It is certainly a chelate, and EDTA would be a prime candidate. The company claims that there are other ingredients to extend the life of the chelate by relieving it of the iron it grabbed from the rust.

Evaporust is very effective, but, as others have said, it isn't cheap. On the other hand, if you need to preserve zinc or other plating, it may still be the best option. Acid based treatments, including vinegar, will attack zinc.

Among common acids, I'm not sure vinegar would be the cheapest. Typical off-the-shelf phosphoric acid products are at least four or five times the concentration of off the shelf vinegar, and phosphoric is a stronger acid in the first place, so diluted to comparable effectiveness, I'd bet that phosphoric is probably cheaper.

Ed

Paul Alciatore
08-21-2016, 10:41 PM
I haven't used Evaporust, but both vinegar and naval jelly are acidic. Vinegar is not as strong as naval jelly and will take longer to remove both the rust and the remaining zinc so it can be easier to control. On the other hand, naval jelly can be applied only to the areas with the rust. You can file that in the "for what it is worth" category.

After removing the rust, you can clean them with WD-40 but I would use something better than that for preventing future rust.