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digdug18
digdug18 HalfDork
7/27/10 1:48 p.m.

I have many bolts and other small parts that I need to remove rust from, but do not have access to a sandblaster. Is there another way to do so?

Andrew

Grtechguy
Grtechguy SuperDork
7/27/10 1:51 p.m.

Electrolysis, Ultrasonic cleaner, some have said vinegar

http://www.stovebolt.com/techtips/rust/electrolytic_derusting.htm

http://www.wisegeek.com/what-is-a-rust-remover.htm

foxtrapper
foxtrapper SuperDork
7/27/10 1:53 p.m.

For small stuff, I much prefer vinegar. Just dump the parts in a plastic buck filled with it, and in a few days, they are rust free. Rinse in water and you're done.

Woody
Woody GRM+ Memberand SuperDork
7/27/10 2:10 p.m.
Grtechguy wrote: Electrolysis http://www.stovebolt.com/techtips/rust/electrolytic_derusting.htm

Photobucket

x2.

ditchdigger
ditchdigger HalfDork
7/27/10 2:16 p.m.

http://www.evaporust.com/

Even avaliable at Harbor Freight

jhaas
jhaas Reader
7/27/10 2:17 p.m.

muratic acid

4cylndrfury
4cylndrfury SuperDork
7/27/10 3:03 p.m.

CLR

ClemSparks
ClemSparks SuperDork
7/27/10 3:50 p.m.

I always thought a rock tumbler would be fun for this (except you could go too far easily).

I've used vinegar and a toothbrush with much success...

Clem

wbjones
wbjones Dork
7/27/10 7:02 p.m.

from GRM tech tips (thanks to JB)

http://grassrootsmotorsports.com/tech-tips/55/

EvanB
EvanB GRM+ Memberand Dork
7/27/10 7:05 p.m.

I've heard molasses works well. You just have to buy powdered molasses at a farm store and mix it with water, then soak the parts in it for a week or two.

mw
mw HalfDork
7/27/10 7:06 p.m.

acid (not lsd)

jimbbski
jimbbski Reader
7/27/10 7:59 p.m.

Concrete cleaner/etcher. It's not muratic acid but phosphorus acid you want. It removes rust but is not as agressive. You can mix it at a 4:1 ratio with water and reuse it many times. I keep a 5 gal. jug of it around, 1 gal acid plus 4 gallons water. I also use it to clean the wheels on my car. The front wheels build up brake dust from the pads & rotors that will leave rust stains on the paint. Spray on some of this acid mixture, wait a few minutes, brush, rinse and the wheels are clean! It doesn't harm the paint as it will dry up before it can effect it.

digdug18
digdug18 HalfDork
7/27/10 9:06 p.m.

I'm gonna try the Electrolytic derusting, and see how things go. The link provided says I need a electrode the size of the container, would 304 stainless steel work?

Would THIS work for the battery charger? I need one anyway. I guess I would set it for 12 volts, but how many amps, I guess that the 55 amps would be rather overkill, and either the 10 or 2 amps would work. I'll let you know how I do and how many times I shock myself.

Suggestions on what to recoat screws/bolts with so as to not clog the threads.

Andrew

digdug18
digdug18 HalfDork
7/27/10 9:44 p.m.

nevermind about the stainless steel electrode, I found that it can cause cancer, I'll stick with rebar.

M2Pilot
M2Pilot Reader
7/27/10 10:42 p.m.
EvanB wrote: I've heard molasses works well. You just have to buy powdered molasses at a farm store and mix it with water, then soak the parts in it for a week or two. Molasses works OK. If you don't have too much to derust,just buy a jar of molasses at the grocery store & use it. Last time I checked the price of powdered molasses at a friend's mill the smallest size he had was around $30. It may be less at a farm store.
Woody
Woody GRM+ Memberand SuperDork
7/28/10 12:04 a.m.

Scroll back up and look at my bucket. I use two pieces of sheet metal. They are bent to cover the bottom as well.

That charger would be fine. I went to Sears and just bought the cheapest, small old school charger that they sold (non-Craftsman). I think I paid about $14. You don't need high amperage. I set mine on 12V, 2 amp.

Pick up a box of Washing Soda from the grocery store to make the electrolyte mix. I use about 2 cups per bucket of water.

I've read that neither increasing the amperage, nor the concentration of the electrolyte makes the process faster. What is significant, though is the surface area of the sacrificial metal. The rust travels in a straight line from the part to the metal. You can use rebar (it's easy), but you really want more surface area for the rusty part to "see".

You do need to keep the part from contacting the metal, though.

lewbud
lewbud Reader
7/28/10 12:31 a.m.

The wirewheel attachment on the bench grinder and a pair of pliers to protect the fingers. Good on surface rust, if pitted see some of the above.

44Dwarf
44Dwarf HalfDork
7/28/10 6:17 a.m.

I've been useing electrolosis myself.

ttp://antique-engines.com/electrol.asp

Works great. I did try a mesh for the anodes hopeing that the increased area would help and the fact i had it laying around. It was used up fast. Now i use a 35 gal TUB from the $ store as my tank and three sections of scrap U chanel that the long one lays on the bottom and the two shorter one just rest on the sides. Works great.

I've seen pictures of a trailer frame in a plywood and plastic swiming pool with an arc welder for power. Man that must have been fun to clean afterward.

Grtechguy
Grtechguy SuperDork
7/28/10 6:18 a.m.

Woody, 2 questions

  1. what gauge is the sheetmetal you used?

  2. Can we see a pic with out water in the bucket?

Ian F
Ian F Dork
7/28/10 6:47 a.m.
ditchdigger wrote: http://www.evaporust.com/ Even avaliable at Harbor Freight

This is what I've been using. Before finding/trying this, I used the wire-wheel method. Evaporust works better if you can wait overnight. I might try vinegar as well... since that's obviously much cheaper. I might even do a side-by-side comparison the next time I have a pile of rusty bolts to clean.

foxtrapper
foxtrapper SuperDork
7/28/10 7:08 a.m.

Electrolysis works well on many things, but not a bucket of nuts and bolts and sundry little stuff. The conductivity ain't worth a shucks on a pile of them. Use a piece of sheetmetal instead of rebar. Size matters, and it goes much faster with the larger surface area of that piece of sheetmetal.

Molasses cleaning stinks. I mean really stinks. For it's the rotting process that makes it work. And when your hand goes into the mess, your hand will stink for days. The stuff you buy at the feed store has lots of finely powdered solids. If you don't filter it first, your parts are laying in a goop that slows down the process.

Instead of a rock tumbler, use the shell cleaner from your gun reloading bench.

Woody
Woody GRM+ Memberand SuperDork
7/28/10 8:31 a.m.

The gage of the metal isn't really important to the rust removal process. Thicker metal would, of course, last longer, but I've been using this sacrificial anode for several years. I just bought two small pieces (non- Galvanized) from Home Depot for a few bucks. They will look like this after the first time you use it. Between uses, I scrape off the big flakes of rust, usually while the plates are still wet.

Eventually, I may take it apart and toss the plates in the sandblaster for a few minutes, just to see if it makes a difference.

Note that the two plates are wired together. That way, I just need to attach the positive cable to the one lug and both plates are charged. I hang pieces from a stick across the top of the bucket so that they don't contact the plates. The same concept would work on a larger scale with a trash can or a plastic kid's pool. Keep the kids out, unless they're rusty. Or Rusty.

I love using this, especially on parts that are either too delicate for sandblasting or if you are afraid of a few grains of sand getting left behind. You can also do pieces with frozen bolts and they will usually release easily after they come out. I've even attached the negative cable to a wire flour sifter and done bolts this way.

When the parts come out, rinse them off with clean water to neutralize the electrolyte solution (base) and then hit them lightly with a wire brush. They come out with a black powdery residue on them that comes right off with the brush.

The bubbles that you see in the last photo are hydrogen gas being liberated in the process, so I always do this outside. You will see them as soon as you turn on the charger. I've heard that you can light them off, though I've never tried.

Photobucket

Photobucket

Photobucket

digdug18
digdug18 HalfDork
7/28/10 11:36 a.m.

nice writeup, i appreciate it, I'll be trying this in the next couple of days. I've got lots of rusty parts that i need to cleanup.

What can I coat the screws with then to protect them from rust? I'd prefer not to use paint, as it will clog the threads.

Woody
Woody GRM+ Memberand SuperDork
7/28/10 11:52 a.m.

Just use antiseize.

digdug18
digdug18 HalfDork
7/28/10 10:40 p.m.

I guess, I'll look into a zinc coating as well, I'm looking for something that will stand up a lot better then just anti-seize.

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