I have been doing a few experiments, or tests of using a process of electrolysis to help remove rust from old parts. The basic process is this: Get some Arm and Hammer Super Washing soda, a plastic bucket, some old steel, or iron scrap, and a battery charger. You put about 2 or 4 tablespoons of the washing soda per gallon of water in the plastic bucket, and mix well. Put the scrap metal in the solution, connected to the positive lead of the battery charger. Connect the negitive lead of the battery charger on the part you want to derust, and put it into the solution without touching the scrap metal. You should see bubbles start rising off the part being derusted. Let the part sit for a while, maybe even a day or two, with the battery charger connected. When the process is done, the bubbles will slow down quite a bit, take the part out and then clean it. It will not be shiny and new, you still have to clean it, but it will clean a lot easier. The part will start rusting again if you do not get it dry. Do not let the part sit in the solution without the battery charger connected. If the current goes too high for the charger, pull part of the scrap metal out of the solution, or mix a weaker solution of washing soda and water.
So far I have used the process to clean the rust off a distributer/oil pump drive, so I could press the gear off, and use the shaft to pre oil an engine, and I also used the process to loosten a broken stud in stainless exhaust flange nut.
electrolytic rust removal
I too have a sandblaster, but a too small air compressor to run it with any kind of a useful duty cycle. Sandblasting also removes good metal. So does muratic (hydrocloric) acid. The box of "Arm and Hammer Super Washing Soda" was $2.39 at Fred Meyer, and everything else I had. The electrolytic method does not remove any good metal, as far as I have seen so far, and seems to only attack the rust. I plan on trying some brake drums next, and then a flywheel I have. I will take pictures of the brake drums, but I only have a film type camera, and there will be a delay while I get the pictures developed.
My compressor can keep up, but you're right.....I can chew up some good metal with the abrasive I use. I don't typically worry about it since I'm not blasting anything that thin or that soft. My abrasive leaves behind a really good "tooth" to paint on.
The muriatic acid pretty much stops at the good metal. My understanding is that it has to be left on the good metal for awhile before it will eat it. It's really only interested in the iron oxide. Same with the molasses, although....if I remember right, it uses a different chemical process.
The acid method is not a very safe method...the fumes are extremely bad. Molasses takes day/weeks. The electrolysis method seems like a really nice option! I'll have to try it, but I think I'll have to get a better batt charger first.
For some of the bigger items.....a childs wading pool should work. I read that somewhere.....sounded like a great idea. You could actually submerge a complete door in something that size.
I'd be lost without my digital camera!!! hhhmmmm....more likely I'd be broke from developing costs!
I guess I'll have to start reading up on this a bit
The muriatic acid pretty much stops at the good metal. My understanding is that it has to be left on the good metal for awhile before it will eat it. It's really only interested in the iron oxide. Same with the molasses, although....if I remember right, it uses a different chemical process.
The acid method is not a very safe method...the fumes are extremely bad. Molasses takes day/weeks. The electrolysis method seems like a really nice option! I'll have to try it, but I think I'll have to get a better batt charger first.
For some of the bigger items.....a childs wading pool should work. I read that somewhere.....sounded like a great idea. You could actually submerge a complete door in something that size.
I'd be lost without my digital camera!!! hhhmmmm....more likely I'd be broke from developing costs!
I guess I'll have to start reading up on this a bit
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Pac. coast Datsun
- Posts: 286
- Joined: Wed Dec 31, 1969 5:00 pm
Heres a link to a video showing this process...
http://www.youtube.com/watch?vKJeXwsl87us
if the link doesnt work let me know...
http://www.youtube.com/watch?vKJeXwsl87us
if the link doesnt work let me know...
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Pac. coast Datsun
- Posts: 286
- Joined: Wed Dec 31, 1969 5:00 pm
Ok i figured it wouldn twork. Go to www.youtube.com & do a search for.......
"rust removal video. The video i saw was from the TV show Trucks but theres a few there showing the same process.
"rust removal video. The video i saw was from the TV show Trucks but theres a few there showing the same process.
Umm...never mind on the pics The newest issue of Rod & Custom has a nice article on how to do it....w/pics
Awesome.....gives me an excuse to go buy a new charger!!
The article talks about not using this method(or acid dip) for parts like steering spindles due to the hydrogen embrittlement. Not sure if they're just trying to be extra careful or if it's really a concern.
The newest issue of Rod & Custom has a nice article on how to do it....w/pics Awesome.....gives me an excuse to go buy a new charger!!
The article talks about not using this method(or acid dip) for parts like steering spindles due to the hydrogen embrittlement. Not sure if they're just trying to be extra careful or if it's really a concern.
Only a concern with structural parts...and there is somewhat of a cure, but still better to avoid the high stress parts.
I'm just regurgitating what the article said. More research is still needed, but for something like a brake backing plate, spare tire/chain assembly....this would be awesome. On thin sheetmetal parts, this would be far better! .....Oooo....exhaust manifolds!!!
Anyway....it's the May issue....should be on the shelf soon, or even now.
I'm just regurgitating what the article said. More research is still needed, but for something like a brake backing plate, spare tire/chain assembly....this would be awesome. On thin sheetmetal parts, this would be far better! .....Oooo....exhaust manifolds!!!
Anyway....it's the May issue....should be on the shelf soon, or even now.
I did the process on a spare waterpump pully that was badly rusted, and It did remove the rust, but it was still pitted, and may not be useable. For the process to work, a good electrical contact is a must. I too saw the article in the program from the Rod and Custom show, but it mentioned useing stainless steel for the sacrificial anode. Another source said not to use stainless, it creates a chromium compound that is poisonous, I heard.
The bucket I do the process in, gets kind of murky and dirty as the process is going, but if I let the bucket sit a day or two after I am done, the rust settles out, I can pour off the washing soda solution, and have not much crud left over to put in the garbage.
I do have several old Datsun brake drums that are my next trial for the process, and also an L-16 flywheel. The flywheel might be held off until I learn more about hydrogen embrittlement.
The bucket I do the process in, gets kind of murky and dirty as the process is going, but if I let the bucket sit a day or two after I am done, the rust settles out, I can pour off the washing soda solution, and have not much crud left over to put in the garbage.
I do have several old Datsun brake drums that are my next trial for the process, and also an L-16 flywheel. The flywheel might be held off until I learn more about hydrogen embrittlement.
That's interesting about the chromium poison being given off. It's one of the things that makes up stainless steel, so I can see that happening, but I haven't seen/heard it mentioned anywhere. Maybe I'll just stick to the steel. It's cheaper and eaier to come up with. Heck....with the plasma cutter, I suppose I can turn almost anything into anodes. I've got some messed up diff housings.....I could cut strips out of them and use that.....they're 1/4" thick or so.
The one thing I like about the magazine article(not the program) was that they used multiple anodes around the bucket. Since it's line of sight, it just helps make it work more evenly.
I was trying to pull a brake drum off an axle today. I was thinking I could pull the entire assembly out of the housing and put it in a bucket and use this process to break the hold on it I'm gonna have to find a 15-20gal plastic wash tub or something
The one thing I like about the magazine article(not the program) was that they used multiple anodes around the bucket. Since it's line of sight, it just helps make it work more evenly.
I was trying to pull a brake drum off an axle today. I was thinking I could pull the entire assembly out of the housing and put it in a bucket and use this process to break the hold on it
I'm gonna have to find a 15-20gal plastic wash tub or something Scrap steel is much easier to obtain. If I had a bunch of scrap stainless, I would sell it. You can get the large Rubbermaid containers at Fred Meyer, in the housewares section, they make great containers for this. Fred Meyer also has the Arm and Hammer Super washing soda. Remember the process also gives off hydrogen and oxygen gas, do it in a ventilated area.