Mew mold preparation question

[Mmacro]

I have two new, multiple-cavity molds, a Lee and MP mold. The Lee is aluminum and the MP is brass.

I’ve ready many like to clean the molds with white gas (Coleman fuel) or mineral spirits... or boil with dish soap, which leaves some kind of protective coating/oxide on the molds.

If going the boiling route do you put the whole thing in the pot? Or do you take the spruce plate, screws, etc. off till you get it down to just the mold (or as close as you can if there are press-fit parts)?

[Mk42gunner]

My latest Lee six cavity, I just sprayed it down with brake cleaner and wiped it with paper towels a couple of times; then lubed the alignment pins, sprue plate contact points and the side of the block the cam presses on with aluminum anti seize compound.

Over the course of a few days I then cast a bit over 1,200 wadcutters for my .38 Specials.

A brass mold I would heat cycle three or four times before casting with, just to get a bit of patina so lead won't stick as easily.

Robert

[Buckshot]

I do as Mk42gunner. Inexpensive carb / brake cleaner. Double check for brass/copper thread protectors on the sprueplate pivot bolt keeper setscrew, and provide same if missing.

Buckshot

[GregLaROCHE]

I’ve seen a lot of different methods for prepping a mould discussed here. I wash mine with brake cleaner followed by hot water and dish detergent. Some times they just need to be used a little to get broken in. Brass could be different. I only have steel and aluminum moulds. When done casting, I spray mine down with Ballistol and then use the same procedure when taking them out of storage.

[RockRat64]

Following Full Lead Tacos method I wash them in hot soapy water and heat cycle 4 times on a hot plate. Getting the mold up to 400° per NOE instructions.

[Burnt Fingers]

Following Full Lead Tacos method I wash them in hot soapy water and heat cycle 4 times on a hot plate. Getting the mold up to 400° per NOE instructions.

Same here. Hot soapy water, then four heat cycles in the oven.

[rintinglen]

I boil them in soapy water, completely immersing them and making sure they stay immersed. Steel or iron will rust at the water line. Then I dry them with a hair dryer. Brass molds then get heat cycled 3-4 times. Lee molds in particular seem to benefit from boiling to remove the cutting oil from the cavities.

[mdi]

I'm a K.I.S.S. kinda guy and I use non chlorinated brake clean most often. I tried mineral spirits but it seemed to leave a tiny but of residue, and acetone or brake clean leaves nothing, just bare metal. I haven't heard of boiling in soapy water leaving a "protective coating" and I don't want anything in my new molds. I clean very well and "season" on my hot plate. I'll lightly lube the pivot points on my mold and heat it to very hot, a bit over casting temp. for a few minutes and allow to cool. Repeat this cycle 4-5 time and start casting. Many/most time I'll get good bullets right from the start, but sometimes it'll take 10 to 15 pours to get 95%-100% keepers.

[Winger Ed.]

I store my iron molds in oil.
I'll wash them in gasoline, then clean/rinse them with carb. cleaner, keep a little 2 stroke oil handy for the sprue plate and get right to it.
I do the same thing with a new one.

Like Grandma's old cast iron frying pan, they get better & better with use.

[farmbif]

my most recent mp molds had very hard to remove cutting fluid residue and I had to clean it by scrubbing with old tee shirt soaked in 90%alchohol

[Petander]

my most recent mp molds had very hard to remove cutting fluid residue and I had to clean it by scrubbing with old tee shirt soaked in 90%alchohol

Brakekleen and dishwash works for me with all molds.

Then four heat cycles and cast perfect.


Yes it takes some patience to cycle them. The other option is sticking bullets, smearing sprue plate etc.