how do you remove rust from bullet molds

[rojo]

hi guys , i am sure many of you have run into this problem and have a few tricks, how do you remove rust from bullet molds ??
in the cavitys and on the flat of the molds that seal when held together , please post, many thanks, rojo

[nhrifle]

Some folks here use a rust dissolver they get at the auto parts store. I just spray them with penetrating oil and scrub with a brass brush then clean with carburetor cleaner.

[Ed_Shot]

Had good luck cleaning a really rusty Lyman mold as you describe with Klean Strip Phosporic Prep & Etch from Home Depot. It will also remove the bluing. Quickly turned it from unusable to totally servicable. I store my steel molds with a coat of penetrating oil and clean with a spray of the blue can break cleaner from W-mart before each use.

[fryboy]

soaking in vinegar also removes rust ( works great for cast iron frying pans ) never had to use it on a mold tho , be aware it takes a lil time , also in part some of it depends upon the amount and depth of rust , pits in any shape and form are problematic at best and if using the steel wool and oil metod one would need to make sure that there is no oil left in the pits

[turmech]

For the one mold I had which came to me already somewhat rusty, I used a small brass wire brush with kroil. I cleaned with the brush fairly aggressively (use your own judgment). Once I finished with the brush I casted several bullets and marked which cavity they came from. I drilled the base and screwed in a self tapping sheet metal screw. I then applied valve lapping compound to the bullets and spun them in the cavities with the mold closed on low speed in the drill.

This is what worked for me, but I could have damaged the mold. My thought was it was no good in its previous condition and in the worst case it would have continued to be no good. The mold now is a pleasure to cast with and in fact is one of best casting molds I have. It was a Lyman 429421.

[Iron Mike Golf]

Evapo-Rust (Harbor Freight and Auto Zone). It removes only oxides. Acids (vinegar, etchers, naval jelly) remove the oxides and the underlying good steel, too.

Any of these remove the blue. A few sessions of casting will restore the "fire blue" to the mold.

[Sgt Petro]

+1 on the Evapo-Rust

[montana_charlie]

Naval Jelly

[Calamity Jake]

+1 on the Evapo-Rust

Hands down

[jameslovesjammie]

It depends on how heavily it is rusted. For really light rust, I've used a pencil eraser or the oil and brush method.

I did have one mould rust VERY badly and I made this thread on using Evaporust to remove the rust. Very good results.

http://castboolits.gunloads.com/showthread.php?124756-Evapo-Rust-Experience-(Pic-Heavy)

[SSGOldfart]

Hands down
Another Eavpo-rust Fan great stuff

[nhrifle]

I think my car needs Evapo-Rust.....

[Sekatoa]

I tried evapo rust as well, and I love the stuff! The best, and safest rust reinvented I've ever used.

[tygar]

Again, depends on amount. Light rust, penetrating oil & brass or stiff nylon brush or 600 steel wool.

Heavy, rust remover (pick your poison) & brass brush then on to fine steel wool.

For the cavities, steel wool & rust remover on a bore brush spun by hand. This will clean out any burrs on a new mold also.

[zuke]

7 hour's per side in stainless steel tumbling media

http://i807.photobucket.com/albums/yy356/zuke_bucket/DSCF2697_zps11f9a29d.jpg

http://i807.photobucket.com/albums/yy356/zuke_bucket/DSCF2696_zps3a3e643e.jpg

[Sekatoa]

[QUOTE=zuke;2765226]7 hour's per side in stainless steel tumbling media

I'm glad someone else tried this and posted the results. I considered it, but also was concerned the peening action of the pins might damage the cavities. The mold you tried it on was a great sample, and looks like it had nothing to lose by trying it.

Now the remaining rust in lube grooves would clean up great with evapo rust. Or, for another experiment....stainless steel tumble with evapo rust in place of the water! I might try that myself, first with a rusty bolt or some or scrap.

[Lead]

Some folks here use a rust dissolver they get at the auto parts store. I just spray them with penetrating oil and scrub with a brass brush then clean with carburetor cleaner.

I do the same keep oil on them while in box but sometimes it's awhile before use so the oil depletes an I hit them with oil an lightly brush with brass brush an hit them with sloriellys brake cleaner.

[zuke]

[QUOTE=zuke;2765226]7 hour's per side in stainless steel tumbling media

I'm glad someone else tried this and posted the results. I considered it, but also was concerned the peening action of the pins might damage the cavities. The mold you tried it on was a great sample, and looks like it had nothing to lose by trying it.

Now the remaining rust in lube grooves would clean up great with evapo rust. Or, for another experiment....stainless steel tumble with evapo rust in place of the water! I might try that myself, first with a rusty bolt or some or scrap.

That mold was in the garbage when I went to a friend's place. I asked for it and he laughed about it. When it was all tumbled he wanted it back.
Never thought of evaporust.And I don't know where to get it around here.

[Le Loup Solitaire]

I have used Evapo-rust on a number of vintage tools that I restored. Good reports are around by folks who have used it on bullet molds. It does an impeccable job on getting the rust off and does not change the appearance of the metal in any way. Finding it used to be a problem, but now it is readily available. Harbor Freight stocks it as well as major auto parts stores. Not particularly cheap, but what is any more? It can be reused several times or more so you don't toss it when done. Does not take away pitting. Some advice on the use of vinegar. I have used it a lot to de-rust cast iron cookware. it works, but you have to watch the time factor. Vinegar has acetic acid in it and that gets rid of rust, but it goes after good metal a the same time and too long in the bath can/will ruin the item. LLS

[Savage99]

rojo
I made a mistake and left 3 molds under my outside casting bench. Rust city. I read a lot of postings, but didn't have any evapo-rust. I thought I would try CLR (Calcium, Lime, RUST), it's what I had. They appeared beyond repair. Anyway, I left the molds in the CLR over night. WOW they turned out pretty. I tumbled them in my Tumbler with SS pins for about 45 minutes, I rinsed them in clean water and used a cotton swab to wipe down the innards. I used a torch to quickly dry them. I then used 600 grit sandpaper, with water, to finish up the two facing plates. Held them up to the sun, nothing but vent lines and darkness. It was a little time consuming cleaning things up but it appears to have worked and the only thing left is to cast some bullets and see how they come out. I will try the Evapo-rust, but the CLR is what I had.

[ohland]

clean with carburetor cleaner.

Er, I'm not good on carb cleaner. From personal experience, it seems to get into the pores (not sure how else to explain it) and when I try to smoke the blocks prior to use, there is a sort of oily deposit left over, not a dry soot. When you try to cast, it does not burn out worth a darn.

RCBS recommends denatured alcohol. I use it with one of those M16 style nylon brushes. I can swirl the small bristles in the cavity grooves so any deposits in the Lub grooves comes out.

Evapo-Rust, +1. Non Toxic, you can pour the exhausted solution down the drain.

http://www.evapo-rust.com/info/evaporust_COMPARISON.pdf
http://www.evapo-rust.com/product-info/faqs/
http://www.evapo-rust.com/buy/retail/
Evapo-Rust® is offered in quart, gallon, 3.5 gallon, 5 gallon, or 55 gallon sizes.

[bobthenailer]

A+ for Evapo-Rust