Care and Storage of Steel Molds

[LenH]

I bought a couple of Lyman molds from an ole timer that was selling everything. The molds were in the original box and were wrapped with VCI paper
and the mold was packed in gun grease. A couple of shots of break cleaner and they came clean. I usually shoot them with a bit of gun oil and wrap in
the paper that came with it.

[Taterhead]

While still warm, I use a light coat of Ballistol. Then a quick hit of dish soap and hot water before casting. I live in dry SW Idaho so we are not prone to get rust.

[curioushooter]

Using a detergent in hot water to clean oily residue is highly inferior to a non-polar solvent. Hot water and detergent work for water-soluble (polar) black powder fouling, but they do very little to remove non-polar oils and greases.

I would add that denatured alcohol is a inferior solvent for removal of oil/greases.To begin with unless you are using laboratory grade absolute isopropyl alcohol (propanol), it is going to contain at least 5% water. Water does not evaporate quickly from a room temp mold, or even a mold hot to touch. The highly volatile non-polar water free solvents found in rattle-can brake cleaner are the cheapest and best way to de-grease a mold by far. Sometimes you can get these for $2 a can at Rural King when they go on sale. They will destroy your skin, though. And they will penetrate all but chemical resistant gloves (they go right through latex and eventually even nitrite). If you want to use brake cleaner safely/healthfully, use it outside so the wind will blow the vapor away from you (and anything with paint on it like your house, garage door, or car!) and hold the mold with a pair of metal pliers or wooden clamp (any plastic will be dissolved).

It is just better to clean molds ONCE and put them away clean wrapped in VCI paper and placed in a bag/box. It's cheaper, faster, and you get less fume exposure.

[curioushooter]

VCI impregnated bag stuck into a mylar moisture proof bag, stuck in a GI Ammo can with oxygen absorber and desiccant. Why take a chance?

Oxygen absorber? You mean a bag of iron powder and salt? I think that is a poor idea. Nearly all salts are absorb moisture from the atmosphere. Unless the container is air tight (and nothing short of a positive pressure vessel really is) you will be attracting moisture to the vicinity of your precious iron molds. Same goes for desiccants (silica gel). All they do is attract and absorb moisture to themselves. Your system will still work, but it is because of the VCI bag (which cost about 100x more than VCI paper). The mylar and ammo can are probably helping. And the O2 absorber and desiccant are unnecessary and probably counterproductive.

If you really want something beyond the belt (VCI paper) and suspenders (mostly air tight plastic bag which functions more to preserve the VCI paper than anything else) then put a heater (like a gun-safe heater) inside a metal box or plastic box with the molds. This will create a positive pressure vessel by warming the air (which expands) inside the box and drive out moisture. Any reasonably tight but non-sealed container (like a metal tool box) will work. A simple metal tool box with a heater would probably work better than any sealed container (like a gasketed ammo can), which will not allow residual moisture to exit.

It is also worth noting that older VCI chemicals are carcinogenic and the modern ones may someday prove to be. It is best to keep this stuff out of your house and especially your kitchen. Don't put a mold wrapped in VCI in your lunchbox, either.

[Dragonheart]

Since I live in the Gulf Coast one thing is a given and that is if it can rust or corrode if left unprotected, it will! So the very best way to keep that from happening is by not allowing the metal to come in contact with air & moisture.
To do this I use gear oil as a coating for my molds. I then wrap them in heavy plastic to keep any sharp edges from cutting the bag, then seal the mold in a vacuum bag. If I want to go a step further I can throw in an oxygen absorber into the bag just before it seals. Sealed this way the molds are completely safe from air/water pretty much indefinitely.

[Static line]

I store my few molds,dry, in my gun safe with the Golden Rod.

[georgerkahn]

Residing in an area which ranges annually from thirty below, to more than 100 degrees above zero, my hunch is the major foe to anything which may rust is condensation -- temp changes being a major cause. On a good many days I've opened the door to my (in garage) shop to actually see condensate on drill press, tables saws, and other tool tables, requiring paper towel drying! I have quite a few steel moulds -- many in my possession for more than fifty years -- and I make sure they're as dry as possible before I put them in Plano 3700 series deep prolatch stowaway, model # 2-3730-05 boxes, which are 14: L x 9.13"W x 3.25" deep. Each has four compartments, which are almost perfect for storing a mould with handles attached in each. I cellophane tape the mould's descript on a piece of paper at each end, and add a teaspoon full or so of Uncle Ben's Long Grain Converted Rice to each.
I have little to no problem finding the mould I wish to use; the Plano box attenuates any condensate-forming temp changes, with the dry rice further prohibiting its formation. It's been probably forty years since I left bullets in the cavities, albeit I generally leave one of my castings in the compartment with the mould, for my later determination if "this mould I really should use?".
What I do.....
geo

[Outpost75]

I coat iron molds with either plain mineral oil USP from the drug store, or Kroil.

Pre-heat the molds on a hotplate before casting and the oil sublimes off so you get good bullets right away.