How to clean contamination from mold?

I have a Lee 6 cavity 105 gr SWC mold. I now get a wrinkles on the bullets from a couple of the cavities.
The wrinkles are around the part line.
My lead temperature is 750F (PID controlled), I run my mold around 380-390F Start to frost at 390. About 400 the whole bullet is frosty.
The alloy is 92-6-2 "hard ball". I use two stroke oil very sparingly for the lubrication.
This mold has dropped good bullets before. I have stripped the mold and cleaned with both brake and carby cleaner. Even tried it when it is hot.
I have check the mold parting faces to make sure there is no blockages in the vent lines. I run moderate flow rate from a Lee 4-20 bottom port pot.

Any suggestions for cleaning the cavities or what else could be causing the wrinkles?

Thanks

Carb cleaner leaves a residue. Brake cleaner does not. Most suggest heating up the mold and letting it cool down several times to help off gas any oil contamination. Some suggest hot water, dawn dish soap and a tooth brush to scrub the surfaces.

Not sure why you are filling the mold slowly. Let it flow freely or you will end up with bullets that have wrinkles. Why do you feel that frosty bullets are not desirable? They are well filled out, with sharp edges and no wrinkles and that is what you are seeking. After the mold is well broken in, you can dabble with the fill rate and how pretty they are. GO have some fun and shoot those frosty bullets. Dusty

Since it has cast good bullets in the past something has changed. I would clean several times scrubbing with a soft tooth brush. 1st time with break cleaner, 2nd tie lauquer thinner and last time with Dawn dish soap really working up a lather and rinsing well with hot tap water. This should remove any contaminants from the blocks. Next look over with a magnifying glass at the cavities ( discoloration or splotches may mean something has penetrated the surface) and then the vent lines for plugs and or dings. If any remove with a light touch and scribe awl ice pick or bamboo skewer

If it's oil (what else could it be?) I would just thoroughly clean with Hot water, dish soap and toothbrush...repeat of necessary.

Acetone leaves no residue.

I once had a similar problem, and it was with one of my favorite, flawless, many times previously used (by me) moulds! Just as I was about to do some major hair-pulling ;) -- a casting friend stopped by and suggested it might be my melt. Huh? It had never crossed my mind, and albeit the product is not my #1 favourite (it removes tin, so I am told), I stirred in some of Brownell's MarVeLux. OMG -- the bullets immediately started dropping wrinkle free. The chemistry, physics, etc. -- I do NOT know. And, I suspect there's a one in a zillion chance that the Marv-fluxing was coincidental to the zillionth mould cleaning... but, I doubt it. If it was me -- based on this experience -- perhaps you can try another mould to see if that will drop good bullets; or, as I did, flux with MarVeLux. Hey -- after all the cleaning you've done to the mould -- it surely may be worth the try. (I generally flux exclusively with pine saw-dust and a bit of red Gouda-cheese wrapping wax).
Best wishes!
geo

I've been known to hit the mold with spray Kroil Oil. That oil doesn't seem to bother the bullet making ability of the mold once it's back to temp.

my PID is at 710° so we're close on temps

I know for a fact slow pours will give me wrinkled bullets.

If you are having problems with mold overheating consider running two at a time. do have to be the same calibers

I will give these a try this weekend.
It is only a couple of the cavities out of the 6. The rest mold OK.
I know one is the second from the front and have tried cleaning it when the mold is ho t or cold and don't seam to fix it.

I use brake cleaner or sometimes acetone. If it's just a wrinkle and you don't see anything in the cavity, a quick blast should do.

If it is just one or two cavities, and you have thoroughly cleaned the mold, I would strongly suggest you check the vent lines on the offending cavities. If they are open, the simply cast as fast as you can. They may not be shiney, but a light frosting on a well filled boolit does no harm, and a wrinkle, unless it affects the base, is more likely to be of cosmetic rather than practical significance.
ON the other hand, if the vent lines are blocked or shallow (LEE, I'm looking at you), you will need to take a scribe or awl and lightly trace the vent lines to assure the trapped air can be pushed out.

George (post #6) might be on to something with the flux. It's been my experience that one flux doesn't do it all.
I use a combination during a casting session. Marvelux, wood shavings from pencil sharpener and Beeswax .
The three fluxes do a much better job than just using one of them.
As bad as people put down Marvelux...it's manufactured for fluxing lead alloy...and it works. Used in combination with wood shavings and beeswax that's about as fluxed as it gets.
Gary

You might try cleaning it with denatured alcohol if you happen to have some on hand.

When I have a problem mold, that's not a simple bullet release from cavity problem.
I go back to the beginning and disassemble the mold and boil it in DAWN. Rinse in boiling water x 2. Scrub with Acetone & CLEAN, NEW toothbrush. Then brake Cleaner with another NEW toothbrush. Then the HEAT/COOLDOWN Seasoning x 4.
This usually solves unseen problems.

Bar Tenders Helper and a tooth brush will clean and polish the mold cavity.
Was first with soap and tooth brush and then use the Bar Tenders Helper to clean a mold.

If the problem is contamination a good scrub with dawn then a soak in acetone will remove any oil residue. Almost all the spray cleaners are acetone.
If the vent lines have a lead build up or at the edge of the cavity, its likely you will just end up scaring the mold by scraping. I would use a 1/1 mix of white vinegar and hydrogen peroxide wetting the surface with a Q-tip and rubbing with pencil eraser dipped in the solution. Not the fastest process, but the mix will dissolve lead. Coating the cavity by rubbing with the pencil lead may also help with the fill out and release.

Lighter fluid with a toothbrush works for me cold. If I get some contamination with it hot, lighter fluid when hot works, but it'll melt a toothbrush.... That was a pain to clean. I am always thinking about the lighter fluid bursting into flames, but it never has, and evaporates almost instantly.