Rust on moulds

[sniper]

I have the chance to buy a mould which has light surface rust. Is there any satisfactory way of restoring the mould so it will give good future service? Thanks.

[Mk42gunner]

I have used a pencil eraser to clean very light rust from mold cavities; seemed to work okay.

Robert

[HeavyMetal]

I used to have a couple of typewriter erasers, the kind that had the little brush on the end, these had just a bit of abrasive in them and worked awesome for just that purpose.

With the advent of computers I haven't seen one of these in years and recently stopped into a Staples and asked if they had any. Gal behind the counter says she remembers them but no one carry's anything like that any more why don't I just buy a computer?

[imashooter2]

Electrolytic rust removal:

http://www3.telus.net/public/aschoepp/electrolyticrust.html

[MT Gianni]

A #2 pencil is your best friend. Sharpen it and go over every bit of the mold, exterior and interior. Thank You, Felix for this information. [it helps to say Thanks, Felix several times while doing this]. When it is completely graphited, dull the pencil point or break it off and use the wood to rub in the rusted areas. Then use the eraser over the mold again. Take before pictures so you can see where the rust was and how bad it was. Gianni

[mooman76]

It wouldn't be a 44 cal. mould would it?

[sniper]

It wouldn't be a 44 cal. mould would it?

Nope.

I have an electronic contact cleaner pen, made of glass fiber. I use it to remove oxidation from my camera battery terminals. Do you suppose that would work, if used gently?

I am hesitant even to think about a bronze brush, a'la Dremel tool at low rpm, though.

If there is pitting, how is too much. and how does that affect bullet quality and accuracy?

Actually, the typewriter eraser or pencil/standard eraser sounds like the gentlest solution.

Thanks again, everyone. :)

[Dale53]

You want to be quite careful using the "ink eraser" on an aluminum mould. Aluminum does not rust but under certain conditions, it CAN corrode. Ink erasers are too aggressive for aluminum.

Dale53

[EDK]

I'd try an oily soft rag at first, then clean it well and see how well the boolits are cast.

Next step would be to lap the cavity with the mildest abrasive I could find and then check it out.

So far, so good. I've never had one that wouldn't clean up with a little lapping.

Good luck,

:cbpour::redneck:

[Ricochet]

Boiling rusty steel, then rubbing it down with fine steel wool, often works well. If you're lucky, you'll get a nice rust blue finish.

[Slowpoke]

http://www.faber-castell.us/docs/index_ebene3.asp?id=21368&domid=1010&sp=E&addlas
tid=&m1=14785&m2=14794&m3=14804&m4=17330&m5=21368

[testhop]

has any body tired the naval jelly rust remover
i usley use the pencil eraserbut was told the naval jelly works

[waksupi]

If you guys will just try the electolysis method once, you won't mess with any other method. It is just plain easy, and effective, and will not harm a mold, as some other methods can.

[Molly]

Boiling rusty steel, then rubbing it down with fine steel wool, often works well. If you're lucky, you'll get a nice rust blue finish.

Ricochet,

A nice touch on that is to rub the rusted areas with a penny or a split neck case (copper / brass won't scratch steel) to get off any really bad rusting. Then go over it _vigorously_ with some '0000' steel wool. This won't scratch anything either. THEN boil it in some detergent / water. This will remove any traces of salts, acids, etc that might have promoted the rusting in the first place.

When the mold is removed from the boiling pot, be SURE to rinse in HOT water to get rid of the detergent, and blot it dry with a clean cotton rag immediately! The metal will be so clean that it can re-rust in a hurry if you don't. This is also a good way to get any storage oils off the mold so you can start casting quickly and easily.

Molly

[Firebird]

I have an electronic contact cleaner pen, made of glass fiber. I use it to remove oxidation from my camera battery terminals. Do you suppose that would work, if used gently?

I wouldn't, glass is actually harder than steel and you will put a bunch of fine scratches into your mold, probably causing the bullets to stick instead of releasing.

[Brownie]

to remove light surface rust from the cavities of a mold I put some light oil on them clean the rust off with some fine steel wool. this works well and does not scratch the mold.

[fecmech]

If you guys will just try the electolysis method once, you won't mess with any other method. It is just plain easy, and effective, and will not harm a mold, as some other methods can.

Amen! You put me on to that a few years ago with a rusted 4 cav Saeco. It worked great, no muss no fuss.

[warf73]

If you guys will just try the electolysis method once, you won't mess with any other method. It is just plain easy, and effective, and will not harm a mold, as some other methods can.

This is the best way to clean any rusty molds or other items (cleaned a 1908 45 with it was amazed how nice it looked after) that you wish to refurbish.

On a really rusty item leave it in the bucket for a few hours.

If you try the electrolysis, best place to get soda ash is at the local pool and spa dealer a small container will cost under $10 and will make probly to close to 100 gallons of solution. I can walk you threw the process of making it if you like. Made mine cheap as possible all parts for it cost me under $20.00 minus the charger of course.

Warf

[Molly]

This is the best way to clean any rusty molds or other items (cleaned a 1908 45 with it was amazed how nice it looked after) that you wish to refurbish.
On a really rusty item leave it in the bucket for a few hours.
If you try the electrolysis, best place to get soda ash is at the local pool and spa dealer a small container will cost under $10 and will make probly to close to 100 gallons of solution. I can walk you threw the process of making it if you like. Made mine cheap as possible all parts for it cost me under $20.00 minus the charger of course.Warf

Yes, I'd like to see it. Can you give us a walk-through of your entire process, along with suggestions of what you consider a good charger.

Thanks,
Molly

[Lloyd Smale]

I allways soaked them for about a week in kroil and then took a brass brush to them. but im interested in the modern way too!!

[imashooter2]

Yes, I'd like to see it. Can you give us a walk-through of your entire process, along with suggestions of what you consider a good charger.

Thanks,
Molly

The quick and easy set up I use:

http://home.comcast.net/~imashooter2/pictures/ERR-out.jpg

http://home.comcast.net/~imashooter2/pictures/ERR-in.jpg

The trickle charger shown works over 24 - 48 hours. A 10 amp charger, overnight. The higher the amperage on the charger the faster it works, but the wires will need to be larger and the solution boils off so needs to be watched. Use a big enough container.

[No_1]

Tidy Cat container. Must be Carpetman Ray influenced......

All joking aside, nice looking setup. Cheap and easy to make with items must of us have around the house. What did you use for solution and what was the formula? Thanks for sharing.

Robert

[Molly]

The quick and easy set up I use:

The trickle charger shown works over 24 - 48 hours. A 10 amp charger, overnight. The higher the amperage on the charger the faster it works, but the wires will need to be larger and the solution boils off so needs to be watched. Use a big enough container.

Now that's MY kinda technology. I assume that's an automotive battery trickle charger ...

What's the solution, and what's the concentration? How do you degrease first, or isn't that necessary?
Molly

[imashooter2]

Now that's MY kinda technology. I assume that's an automotive battery trickle charger ...

What's the solution, and what's the concentration? How do you degrease first, or isn't that necessary?
Molly

Yes, an old 6V/12V motorcycle charger I had laying around. I use that one on 6V because the internal circuit protection keeps cycling if I turn it to 12V. I also have a 2/10 amp 12V Craftsman charger that I got 30 some years ago that will run continuously on 10 amp but I usually turn it down to 2 amps when I need to leave for work or go to bed. I've boiled off the solution before running it overnight on 10 amps.

The official formula for the solution is in the first link I posted on the previous page. Baking soda works, but washing soda works faster. No idea why. In practice, I use the very scientific "stir some in until it doesn't dissolve any more" method. Undissolved powder on the bottom of the bucket doesn't hurt anything.

I degrease by boiling in soapy water, same as I do for all new to me molds. I don't know if that's a necessary step as the alkaline solution might just cut through any grease, but it can't hurt.

[Newtire]

I agree that this method works the best but I have had results in much less time than overnight myself. I use the same trickle charger 1-2 amp set on 6 Volts (12 Volts works too with mine). I bought the charger in 1973 to keep my old Norton battery charged.

Thanks for the great pictures & I like the nice bent piece of metal & wood support hanger you thought up to keep the charger terminals out of the solution.

[imashooter2]

I agree that this method works the best but I have had results in much less time than overnight myself. I use the same trickle charger 1-2 amp set on 6 Volts (12 Volts works too with mine). I bought the charger in 1973 to keep my old Norton battery charged.

Thanks for the great pictures & I like the nice bent piece of metal & wood support hanger you thought up to keep the charger terminals out of the solution.

I agree that lightly rusted items like molds will generally clean pretty quickly. Heavily rusted items can take considerably longer. Since you can't damage your part by leaving it in too long, I generally do just that and make sure all trace of the rust is gone, gone, gone. I have to sleep anyway and may as well let the device work while I do.

You can't see it in the picture, but the steel strap is bent into a U with the back leg blocked off by the paint stirrer stick. It's sticking up 3 or 4 inches. That gives the part better exposure.

[DLCTEX]

+1 on oil and 0000 steel wool. DALE

[Newtire]

Very nice,

I was thinking I'll have to get a long plant box made out of plastic or something similar & de-rust a Colt Lightning Action & barrel I have.

Many thanks for the great ideas

[imashooter2]

Very nice,

I was thinking I'll have to get a long plant box made out of plastic or something similar & de-rust a Colt Lightning Action & barrel I have.

Many thanks for the great ideas

Plastic rain gutter, glue the caps on and use several strips of steel strap along the length connected by wire for your anodes.

[Ricochet]

Ricochet,

A nice touch on that is to rub the rusted areas with a penny or a split neck case (copper / brass won't scratch steel) to get off any really bad rusting. Then go over it _vigorously_ with some '0000' steel wool. This won't scratch anything either. THEN boil it in some detergent / water. This will remove any traces of salts, acids, etc that might have promoted the rusting in the first place.

When the mold is removed from the boiling pot, be SURE to rinse in HOT water to get rid of the detergent, and blot it dry with a clean cotton rag immediately! The metal will be so clean that it can re-rust in a hurry if you don't. This is also a good way to get any storage oils off the mold so you can start casting quickly and easily.

Molly
Thanks, Molly! The copper/brass scraper is a good idea.

[warf73]

Yes, I'd like to see it. Can you give us a walk-through of your entire process, along with suggestions of what you consider a good charger.

Thanks,
Molly

If you don't mind waiting till the weekend I'll give you a complet run down of items and pics as I construct one for you to see.
I'll take alot of pics to make it ease.


Warf

[warf73]

imashooter2

Nice set up does it get the rust off 360* around the mold or do you have to move the mold?
My set up is 360* is why I ask.

Warf

[imashooter2]

imashooter2

Nice set up does it get the rust off 360* around the mold or do you have to move the mold?
My set up is 360* is why I ask.

Warf

I've read on the various how to sites that the action is only line of sight to the anode, but I've never seen that to be true. Perhaps because I'm using a lower amperage over more time? A stronger solution? Whatever, it cleans 360 degrees for me. I did make an anode out of an old cookie tin once. I figure that for serious exposure to the part, but it made no difference in result I could see.

The pics I show were of an expedient set up made quickly with stuff I had laying around. I did try to maximize anode exposure with what I had because that was what the instructions I'd read say to do.

I'm looking forward to the pictures of your setup.

[qajaq59]

Electrolytic rust removal:

http://www3.telus.net/public/aschoepp/electrolyticrust.html

Sometimes that search function is REAL handy. Now I can apparently clean some surface rust off my old molds without ruining them. I'll give it a try tomorrow.

Thank You imashooter2. I owe ya one.

[Will]

Navaljelly works and is simple to use. It will remove the blue also. I used it on one and it worked fine.