Reconditioning and rust

[ozzie34231]

I see pictures of very badly rusted machines that get reconditioned to beautiful, new looking machines.
What are the ways re conditioners deal with rust?

Ozzie

[RICHARD ZASTROW]

Ozzie, There are many ways to remove rust. I like rubber gloves, steel wool, deisel fuel, automatic transmission fluid and elbow grease. There are commercial preparations as well. Of those, I like Kroil. I'm sure someone will suggest water displacement 40th attempt AKA WD-40. lol

After removing the rust, there is usually some/much additional effort in correcting surface damage and geometry correction.

Dick Z

[ozzie34231]

Thanks Dick,
Do I read you second paragraph to say that a new looking machine that was fairly rusted has had the ways re machined or scraped?
I've removed rust but never get anything like shiny new metal.

Ozzie

[NC Cams]

We've picked parts in muriatic acid - right from the jug - as in the type you etch floors wtih and it TOTALLY removes rust from sound steel. It does not seem to hurt the good, sound metal if you watch what's going on. The steel has a matte finish after etching and can be buffed to a luster. Any pitting from the rust will remain forever as oxidation ha taken its toll - the acid TOTALLY removes oxidation/rust however and other stuff you don't need or want.

We've picked cast iron and, depending on the alloy, it cleans it nicely. Some alloys, however, the acid attacks with wild abandon. Hardened alloy steels are sometimes left OK and sometimes ATTACKED - It varies. Try test parts that are not particularly precious if you're unsure. Forget aluminum or any zinc plated parts as the reactions are not pleasant.

You can "soften" the action of the acid by simply adding distilled water. The acid can be used over and over and it is not particularly expensive. use, nutralize (backing soda and wter) and dispose of properly as, after all, it is a hydrocchloric acid based chemical!!.

[RICHARD ZASTROW]

Ozzie, As usual, NC is also correct. I don't like the acid thing because it stinks and I can't stand the smell. lol I thought your question involved severely rusted components. That usually includes pitting which on machine ways is not welcomed. The pitting can be removed by filling (I don't usually recommend that) or resurfacing by grinding, scraping or? as you noted. I've seen ways that look fine after NC's acid cleaning and then polished by stoning etc. However, you should still check the geometry after polishing to be sure it still has the capability to hold the tolerances you require.

There's some fine looking polished junk on e-bay every now and then, buyer beware and all that.

Dick Z

[ironDigit]

if its real precious electrolysis seems te best in MHO.

or anything acid from coca-cola to hydrocloric chemicals ,and some rubbing is almost always involved.steel wool and scotch-britepads seem to bust-rust as well as leaving a nice finish.after using acids on your projects always neutralize with baking soda or the rust might be back faster then you can rub.

trow some searches for electrolysis and you'll find better then i can explain in no time.

good luck.

[martinw]

Dear Ozzie,

Try this...
http://www.cnczone.com/forums/showth...highlight=rust

Post two has a link to electrolysis details..

Best wishes

Martin