How to remove rust chemically?

[J Miller]

I am slowly disassembling a very badly rusted Singer Mdl 99K machine. I do not know how it came to be so rusted but it was seized up tight. I have it freed up somewhat but I will have to totally strip it down to it's last part to totally clean the rust out of it.

Some of the plated parts are coming clean with a fine wire brush on my Dremel tool then Mothers Mag & Aluminum polish.
However some of the non plated parts are being stubborn.

For instance I've gotten the bobbin carrier clean enough that it will function but it is still rusty. I need to strip the rust all the way off chemically. There are just way to many curves shapes and groves to be able to do it with a wire brush.

What do I use for this? I've tried several things including:
Liquid Wrench rust remover and penetrant,
Hoppe's #9
Full Strength Simple Green
White Vinegar

They all do a little, but not what I need.

Any ideas?

Joe

[Blaine]

Some stuff called Naval Jelly...it is strong, though. It will burn your skin and maybe go farther than you want. At least that's how I remember it from years ago.

http://www.lowes.com/pd_117792-133-01-8 ... Id=3009567

[foxtrapper]

Should work- http://www.thecarycompany.com/container ... NAodE3uPnA

[Bruce Scott]

Joe, Have you considered this method:
http://schoepp.hylands.net/electrolyticrust.html

For more sites:
http://www.google.com.au/#sclient=psy-a ... 9g-v1&aql=&

[gcs]

The vinegar should work over time, but you can really de-rust something fast with acid, muriatic or sulphuric acid can be bought in any box store.
Just watch it closely and neutralize with baking soda when your done. Shouldn't hurt the steel parts but any plating may not fare so well.

[J Miller]

Blaine,

Duh ..... I had some of that out in the garage. Forgot all about it.
Will give it a try.

Bruce,
No, never consider it. I'll check it out.

foxtrapper,

Will try that if the Navel Jelly doesn't do it.

Joe

[mad mucus]

Years ago I bought some stuff in a small spray bottle from an auto accessories shop(forget what it was called) that was IIRC a clear acid spray that dissolved surface rust and rinsed off with water, prior to painting.

[Scott Young]

I would use a molasses bath. If you search the net you will find how it works.

http://www.jalopyjournal.com/forum/show ... p?t=557996

here is one link

[MacEntyre]

lemon juice, followed by water, then alcohol.

[GonnePhishin]

I frequently watch the show "American Restoration" in which the owner of the company [name is Ron Dale?] will restore anything a customer will bring into his shop. I think he's somewhere is Kalifornia.
But my point is they will take everything apart and will sandblast the parts where they can to get all of the rest off before replating or painting. Have you considered sandblasting?

[Cliff]

Phosphroic (sp?) acid. Will remove rust without hurting good metal. Method used by professional painters of metal. Does leave a slightly etched surface. Check at a paint store. This is the same stuff used in very small amounts in Coca Cola. Naval Jelly is also worth a look. I think it might depend on how much surface you want to remove the rust from. Just a thought. Another method used by museums in salvaging metal is to use steam, turpentine and if possible a vacum cabinet to pull oxygen out of the rust, I believe the steam opens the pores and allows the turpentine to pentatrate. They do use this on some historically significant firearms as well. Enjoy.

[MacEntyre]

phosphoric acid is good... perhaps hard to find.

You can get Oxalic Acid in fiberglass cleaner or toilet bowl cleaner... it's a weak acid, but stronger than lemon juice.

Be sure to have on hand some water to flush the acid, and alcohol to flush the water.

[J Miller]

Lots of cool suggestions. A sewing machine is, older ones anyway, cast iron for the most part with some finely machined parts. The cast iron parts are OK for the most part. It's just the finely machined parts that are rusted. I got the one that started this thread, the bobbin carrier, cleaned up by soaking it in Navel Jelly, then rinsing it, and then using the fine brush on the Dremel to finish getting most of the rust off. A little more soaking in Hoppe's and I got the two microscopic screws out of the tension spring. So, it's coming along.
Thanks for all the suggestions. I'm going to make a list of them for future projects.

Joe

[Scott Young]

Phosphoric acid doesn't remove rust it convert it to a different stack pound. It doesn't take you back to raw metal like the molasses does. I use a lot of phos. I prefer Ospho if you are are going the phos route.

[Old Time Hunter]

Joe,

Try this stuff, works well on antiques as it does not damage the metal under the rust.

http://www.bluewonder.us/RustRemovalwit ... eaner.html

[mikld]

lemon juice, followed by water, then alcohol.

Then add some sugar and you got a gimlet...

[kragluver]

+1 on the muratic acid. I found that it works great for quickly removing old bluing and any rust. I've polished and reblued several old rifles and muratic acid is the fastest thing I have found for removing old finish and surface rust. As others stated above be sure and neutralize the acid after dipping or wiping down the part. Muratic acid is available in almost any hardware store. We always have quite a bit on hand as we use it to keep the ph in our pool at the correct level.

[J Miller]

Well,

I have the machine apart pretty much as far as I'm going to take it now.
I ended up using Navel Jelly on the one part then went back to vinegar.

Here is what I found out.
The last time I used white vinegar to remove rust I put the rusted part in an aluminum tray and it took off. It was bubbling like crazy after a while.
This time I put the rusted parts in a plastic tray and then the vinegar and nothing happened.
A couple nights ago I went back to the aluminum tray and it worked again. I'm guessing the aluminum does something that promotes the chemical action.
I also tried an aluminum cat food can and got no results. It is coated inside with something and no reaction.

O.T.H.,
I'll check the Blue Wonder out.


Joe

[jhrosier]

For what it's worth, naval jelly is mostly phosphoric acid (65-70%).
http://www.google.com/url?sa=t&rct=j&q= ... E5haA6dz8g

Jack

[J Miller]

Well, that explains why it smells so bad.

Joe

[olyinaz]

I'm really surprised someone didn't mention Evapo-Rust. It's amazing stuff. Usually available at auto parts stores:

http://www.harborfreight.com/1-gallon-e ... 96431.html

Here's the label, give it a read:

http://www.evaporust.com/Images/DERlabel.jpg

Oly

[J Miller]

Oly,

That looks like something I'm going to try. I still have some rusted parts to clean.

Thanks.

Joe

[1894cfan]

IF you feel like trying something else.....
I had gotten an AGI instruction tape on the Winchester 94, and in it the instructor used Simple Green to clean and de-grease the parts, also said it would work on rust. Anyway, I had gotten some and used it on my Dad's '77 94 trigger/hammer strut leaf spring that was getting a bit rusty, and after a bit of soaking and brushing cleaned it up pretty good, and what the brushing didn't get off the Dremel with a wire wheel did. HTH

BTW, I FINALLY got around to doing something about the '41 94 extractor spring that I had posted about some time back! Got it taken down enough to get the bolt out and removed the extractor and stoned the burrs off and beveled it a bit to make it ride over the case rim easier, I had noticed that it was scratching the rim a bit, too (there was a bunch of brass shavings under the extractor and into the channel). The Win 94 sure is easy to work on, once you know how! Now the next step is take it to the range to give it a bit of a work out.

[J Miller]

One of the things I tried was Simple Green. I guess the rust on this machine was too much for that. It cleaned the parts, but didn't do much for getting rid of the rust.

Sewing machines are kinda like 94 Winchesters. The look more complicated than they are. Well, the older straight stitch ones are anyway.

Glad you found the burrs and roughness and got rid of it.

Joe

[93marshooter]

Soak parts in vinegar over night, wash clean.

[J Miller]

93marshooter,

That's what I did with the last batch of parts. Seemed to work better than letting them soak for longer.

Joe

[Blaine]

I remember from a Pawn Stars show that they would sandblast with walnut shells if it was really delicate and easily damaged...

[J Miller]

Sounds good. You got an extra blaster I could borrow?

Joe

[Blaine]

Sounds good. You got an extra blaster I could borrow?

Joe

Load some walnut shells up in a shotgun shell....

[J Miller]

Sounds good. You got an extra blaster I could borrow?

Joe

Load some walnut shells up in a shotgun shell....

Ooooo that would be fun .... but .... I don't have a shotgun

Joe