Cleaning moulds

[Ben]

I'm certain that all of us have a " proven technique " that we have adopted and use whenever we get a new mould.

I'll take a cold mold that has traces of oils and / or grease in the cavities, I'll remove the sprue plate and spray the cavities , and the sprue plate with Brake Cleaner. As Jim has pointed out don't do this on an Alum. mould when it is hot ! Sometimes I even use a soft nylon brush to move the Brake Cleaner around in the cavities.

I will often times give a mould 3 treatments with the Brake Cleaner. Then I'll blow it out with 100 psi air. Get a good grip on that mould halve when you hit it with the compressed air.
Precision moulds and concrete floors don't get along with each other very well.

Then I'll set the re-assembled mould and handles on the edge of the pot for about 5 minutes to help bring the mould's temp up to where I can cast with it and KNOW that there isn't a trace of any liquids on the inside of the mould. We don't want a visit from the Tinsel Fairy !

As soon as the mould is hot enough to cast with, I'll begin to cast 15 or so bullets from each cavity. If I'm still getting wrinkles and I think the mould is up to temp., I'll take a convention cotton Q Tip and soak one end in plain water. Then I'll move the Q tip round and round in the cavity. Steam will come out of the mold cavity. Kinda like steam cleaning an engine.

I do not use anything on the Q tip except plain water. I may dip the Q tip into water 4 or 5 times with this method. Then blow out the mould with compressed air again.

Then I'll set the mold back on the edge of the pot to bring it back up to proper temp.
I'll try it again. Eventually using this method , you'll have the mould totally cleaned of all oils, waxes, and petroleum compounds.

It works well for me, try it !

Ben

 

[Ben]

Whether or not you choose to use a butane lighter to put a thin film of carbon ( soot ) into the mold cavity after it is clean is up to you.

Many casters do it, -------Many wouldn't think of doing it.

Ben

 

[S Mac]

All I can add to your technique is that many times I will use the Q tip with the brake clean in the cavities.

 

[Brad]

I usually scrub them with warm water and dish soap. If we have some on hand Comet does an excellent job.
The last Lee mould I used I didn't even bother to clean. Got it hot and started casting. Took a few pours before bullets came out with no wrinkles but it certainly was a fast and easy method.

I do find that NOE moulds, and some Lee moulds, need a few heat cycles to get going right. It is almost like the heat draws more oil from the metal. Must be an Al mould thing.

I do know a guy who used 2 stroke oil to keep moulds from rusting. He just got the mould hot and the oil burned off the next casting session. I never tried it but it certainly sounds like a viable option for iron moulds in rust prone regions.

 

[Ben]

Yes, Brad......I've also noticed that NOE and Lee aluminum moulds will require 2 or more heat cycles.

Seems the heat draws the cutting fluids out of the pores of the aluminum. When that happens, you're back to wrinkled bullets again.

Ben

 

[Ben]

All I can add to your technique is that many times I will use the Q tip with the brake clean in the cavities.

Yes, you're right, so have I.
It works.

Ben

 

[35 shooter]

I also use the brake cleaner (non chlorine) type to clean new and old moulds.
I let it run off on it's own for a moment and wipe the whole thing down with a clean dry piece of old t shirt.

After pre heating the mould and sprue plate it's good to go right off the bat, or at least within 10 to 15 casts...depending on how well i do the pre heat thing.

I also spray the moulds with wd40 to protect sprue plates and screws after use from rust. The next casting session they get the brake cleaner treatment again. Only takes a moment while the lead is melting.

 

[Ben]

Buddy,

Success is obviously the goal.

Some will reach that goal with your technique, some with mine, some with hot soapy water, some with 5 or more other techniques.

As is often times the case, there is more than one way to do this.

 

[Brad]

Buddy,

Success is obviously the goal.

Some will reach that goal with your technique, some with mine, some with hot soapy water, some with 5 or more other techniques.

As is often times the case, there is more than one way to do this.

Truer words will never be spoken. Do what works for YOU. There often is not a single "right" answer.

 

[35 shooter]

Buddy,

Success is obviously the goal.

Some will reach that goal with your technique, some with mine, some with hot soapy water, some with 5 or more other techniques.

As is often times the case, there is more than one way to do this.

Lol i was actually just agreeing about the brake cleaner....works great at cleaning oils and whatever off the moulds.... really helps keep them looking like new!

 

[Ben]

I understand what you're saying Buddy.

The point I wanted to make ( particularly for those that are new to casting ) is that there are many methods that will get a mould clean and able to cast good bullets. No one method or technique is magic.

If a caster's mould cleaning method yields cast bullets with good fill out, and no wrinkles, his method of cleaning his moulds must be a good one.

Ben

 

[62chevy]

Well said Ben as my method of a tooth brush dish soap and tooth paste works just fine for me.

 

[Dale53]

Ben;
I have no quarrel with your method.

Mine is a bit simpler - I use a toothbrush with Dawn Dishwashing Liquid (the brand MAY be important due to residuals after cleaning) and hot tap water. I scrub vigorously, but carefully, then rinse THOROUGHLY with hot tap water. Leave the molds open to air dry, then immediately go to the casting barn and pre-heat with a metal surface hotplate while my casting metal is coming up to heat (about 30 minutes). Over the years I have never had a failure with this method and it is safe to use. Some solvents can damage aluminum and I sure don't want to take a chance on damaging a fine Mihec or NOE mold.

If you and I are lucky, we'll get to exercise our respective cleaning methods on a new NOE mold shortly, huh?!

FWIW
Dale53

 

[Ben]

I can't wait.
I've got a hungry T/C that is waiting.

Ben

 

[Missionary]

Greetings
Another Dawn and hot water mold cleaner here. All my molds get motor oiled and wrapped in plastic bag or wax paper after use and waiting for my return to casting at that location whether east ILLinois or here in Peru. Dawn seems to work well. I do the same with new NOE or Lee aluminum. But it is interesting reading other methods. That is what lead my to Dawn years ago. Just read today there is a Dawn Ulta.
Mike in Peru

 

[Rally Hess]

I've always cleaned new moulds with alcohol and a toothbrush. I believe either Lyman or RCBS used to recomend it in their directions. Now I use palmolive and hot water. Dawn is the only thing I've ever found that I am allergic to. Makes my hands turn red as soon as I use the stuff.
Evidently Dawn has changed their formula in the last ten years or so. A taxidermist buddy of mine uses Dawn to degrease the skins of trout he is going to mount. He had a bottle of the stuff in his shop that he'd been using for a long time. It ran out and he replaced it with a new bottle. Used the new stuff on a customers trout and it melted the skin!He said there was just a layer of scales left in the bottom of the container. It was an exceptional trout and took him a year and a half to find a replacement.

 

[James W. Miner]

WD-40 is the worst stuff ever but now and then I use for a lube when I cut a mold. Dish soap and hot water is enough to get the first casts perfect. It really is all you need.

 

[Elkins45]

I have become a recent fan of Dawn and hot water for aluminum molds, followed by taking a propane torch on low and heating each cavity for a few seconds.

 

[62chevy]

I have become a recent fan of Dawn and hot water for aluminum molds, followed by taking a propane torch on low and heating each cavity for a few seconds.

I like the torch way of heating when my hot plate is being use for casting.

 

[Missionary]

Greetings
Those propane torches are a big help getting 6 cav molds up and running. The 2 cav molds get placed on the pot rim before entering the rotation but those 6 cavity beasts are a whole new adventure. Especially the tiny little 60 grainers. Been thinking about removing as much bottom mold metal as possible.
Mike in Peru