Electrolytic rust removal

[NickWheeler]

As I mentioned in another thread, I recently bought two milling machines and a lathe with a whole load of tooling. I had planned on keeping the stuff in storage until I move to a larger shop (buy it when it's available and you have the cash... 'ya know ).....

Well, it didn't work. The storage was NOT weatherproof at all, and EVERYTHING got rusty. I put everything on hold, got the machines in the shop and cleaned/waxed/oiled....

I really didn't want to tackle the tooling, but if you don't stop something that's rusting here in Washington state.... pretty soon it's junk.

I've mentioned electrolytic rust removal here in the past. Normally I use a 25 gallon plastic container, but I'm doing small parts so a crappy little 2.5 gallon bucket works fine.

The bare bones is a battery charger set on full power with the positive lead hooked up to a "sacrificial part." I use stainless, so I just wipe it down afterward. If you use carbon steel, it will turn to crud. You connect the negative to your part. There is baking soda in the water (about 3 or 4 TBS in this little bucket).

The rust comes off the part you don't want rusty, and is redeposited on the sacrificial piece.

For some things, it's easier to just oil/wire-brush... But for parts that are hard to get into, or where you really want the rust off down to clean metal withOUT doing any stock removal on the part.... this is the way to go. Unless you had severe pitting, your part will come out unscathed other than some discoloration.

I wipe it down with a rag and then either Scotchbrite it, or use the wire wheel on the Burr King. The wire wheel is more better

Here's the set-up-

You can see the bubble action going on. That's an NMTB 50 spindle for a Cincinnati mill. Obviously it could have used a larger tub

The trusty wire wheel

I didn't think to take a before pic, but this R8 collet DID look just like that horizontal spindle that's in the bucket.

 

[Plain ol Bill]

Rust is insidious as you know Nick. Yeah, clean everything up and apply some good rust preventive to it. It has been my experience that once rust starts on an item it will come back easier after that also. Storage has to be dry and if on concrete it needs a vapor barrier underneath.

 

[JasonSCarter]

Thats a really cool process! Buuuuuttttttttt........Dont do to much of that in an enclosed space Nick. All those lil bubbles are HHO (brown's gas) litterally 2 hydrogen's and an oxygen. Im sure you can see how dangerous that can get...

Jason

 

[David Loukides]

Man I was really excited until I Saw the Hindenburg!!!!

 

[fast14riot]

this is a great mini tutorial. This process is also very handy for rusted bearing surfaces where you don't want to scratch the polished surface. It also does not etch unrusted surfaces. I used it on the crank and connecting rods from the engine I posted on the what's on your bench thread. came out excellent.


-Xander

 

[Salem Straub]

Don't you think it would be much quicker, easier, and less dangerous just to let me haul that rusty ol' stuff away?

 

[Mike Quesenberry]

I learned about this electrolytic rust removal a couple years ago and love it. I cleaned my anvil, swedge block and a whole mess of blacksmithing tools I got at a garage sale. I used multiple pieces of rebar clamped to the sides of a plastic container instead of stainless.

Does the stainless do a better job of pulling off rust?

Jason good heads up on the HHO, I remember reading it had to be done outside from the gases given off. Big BOOM bad!

 

[chris609]

Fantastic! Cant wait to try this I have lots of tooling to a lathe Im restoring. Thanks for the tutorial

 

[NickWheeler]

I know it's completely counter intuitive to take a battery charger, hook both leads up to steel, submerge them in water and turn it on!!!!

But it really works well and is safe. I've been using this method for like 4 or 5 years now with great results. The one thing you do NOT want to do is touch the two steel parts to each other or they WILL arc and your heart will skip a beat or 6 Ask me how I know... I'm very careful about it... but Shadow didn't know. :foot:

Here's a pic that will help show how great this process really is. You saw how crappy the Cincinnati horizontal spindle looked in the first and second pic. In case you missed it, here's part of it that has not been in the bucket/wire wheeled yet.

And here's the end that was in the bucket in picture #1 and 2 in this thread AFTER it was wiped off and wire wheeled real quick.

I chose to showcase tapered tooling because it's a prime example of something that CANNOT have a crusty, bumpy surface.... nor can you just grind the crust off and still have a proper fitting taper.

I agree with my buddy Bill that once something has rusted, it seems like the door is open for the rust to come back all the easier. Maybe that's not true, but it sure seems like it. With this process you remove ALL the rust and it seems much easier to keep it away. My hang-up with just using the old WD-40 and wire brush trick, is you get the high spots but there's almost always still rust in the low spots. For something like an anvil.... who cares!?!?! (oh wait... guys like me and Mike Quesenberry! LMAO!!!) But for things like a precision tool.... I know most folks DO care.


Many of the folks that use this a lot do things like antique tool restoration and will recommend you follow the dip with gray or white Scotchbrite as that won't scratch the surface and often won't even disrupt existing bluing..... We've all watched enough shows like Antique Road show and American Pickers to know that collectors like "ORIGINAL PATINA" but don't like rust... and this method really works for that.


For stuff like what I'm doing.... the coarse maroon Scotchbrite or the wire wheel work just dandy... but WILL remove old bluing.

Another BTW--- Supposedly "baking wash" works better than baking soda.... But I always have baking soda in the shop and I know it works well for me. I suppose one of these days I'll be in the store with $4 and remember to try the "baking wash."

Hope this helps some of you guys to try something new2u!

 

[NickWheeler]

Forgot something else... you guys are right about doing this in a well ventilated area. It doesn't really look like it in my photos... but I'm doing this in the opening of the big garage door.

Thanks for pointing that out!!! :thumbup:

Mike, the ss sacrificial piece doesn't work better than carbon, it just allows me to wipe it down every once in a while and keep using the same piece of metal.

 

[fast14riot]

yeah ill second it that sodium carbonate works better than sodium bicarbonate. Woodworking or well stocked paint stores would have it as well but called "whiting" its used for pulling oils out of wood.


-Xander