Lead Smears

[Delmonico]

Was just talking to a friend here at work about casting and I made a suggestion that I find out works well.  We all know not to open a mould to quick, but we all do it from time to time.  If you do, often you build up a lead smear on the sprue cutter and the top of the block.

If you do, just grab a carpenters pencil and "erase" with the pencil, the graphite won't hurt anything and you have no risk of damaging the mould like a razor blade that most use.

Don't know if I'm the only one ever figured it out, but I've never seen it mentioned anywhere before.

[Silver Creek Slim]

I'll have to try it. Thanks.

Slim

[Dick Dastardly]

Well, it's not truely pure graphite, but it works well.  So does the "spray" on mold release agents.  Don't go usin' 'em in an aluminum mold cavity cuz it causes problems, but the stuff works great on the backside of the sprue cutter plate.

Thanks for the carpenters pencil trick.  Yes, it works, but they are not all the same.  I'd give 'em a test and keep the good ones for just that purpose.

Here's a trick for smeared lead on the mold blocks or sprue cutter.  I use a hard maple scraper to remove the smeared casting metal.  From now on, I'm going to have a good graphite carpenters pencil handy also.  Sometimes I do hurry a bit. . . .

DD-DLoS

[Montana Slim]

Dick cautioned use on aluminum molds & I'll second that and emphasize: Graphite is highly corrosive on aluminum.
I recommend keeping it away from any steel parts that come into contact with an aluminum mold as well.
Personally, I'll stick to the razor blade & keep my band-aids handy.
Slim

[Delmonico]

I had never heard that graphite will cause corrosion in aluminum before.  Would never have even thought of it, but a check with Wikipedia came up with this.

The use of graphite is also limited by its tendency to facilitate pitting corrosion in some stainless steels, and to promote galvanic corrosion between dissimiilar metals. It is also corrosive to aluminium in presence of moisture. The US Air Force banned its use as a lubricant in aircraft and its use for automatic weapons is discouraged as well.  Even graphite pencil marks on aluminium parts may facilitate corrosion.


I never thought about the galvanic properties since it in is self is a very stable mineral. 

[Noz]

bullshop@wildak.net
These people make a sprue plate lube. Works wonderfully. No smears on mold or plate.

[Grizzle Bear]

How curious!  I have been using Rapine's Mould Prep, which is graphite in alcohol, for years on my aluminum moulds.  I have not noticed any problem.

Grizzle Bear

[Delmonico]

I'm guessing from the information I've found in a short amount of searching that it is more of a problem if the aluminmum is kept in a damp enviroment where it can draw moisture.  At this point I think the rust on the steel parts would also show up.  It is food for thought.

[sundance44`s]

I uasually just open my mold and dunk it into my melting pot .. it`ll remove any build up on the mold .. and let ya know if your melt is hot enough or not .A friend of mine heats his mold that way he puts it in the melt and if lead sticks to the mold .. his melt isn`t hot enough .I haven`t tried that but i do dunk mine to remove a problem i caused from opening the mold too fast. I uasually use a candle to soot up the inside of my mold and the spruce cutter too before i start casting also keeps lead from sticking so much even from the start when the mold isn`t quite hot enough yet .

[Delmonico]

Kitchen matches lit and let burn a few seconds will lessen the chance of putting a trace of wax on the mould.

[Noz]

I opended a new Lee mold Friday, lubed it with the Bull Plate Lube mentioned above. Ran around 400 round balls with no smearing and no galling. I was running the mold a max temp because I was in a hurry to get on to another project.

[Paladin UK]

Okay..

Ya got me a mite confoozed here pards.

Ya say that.....

Graphite is highly corrosive on aluminum.
I recommend keeping it away from any steel parts that come into contact with an aluminum mold as well.

Even graphite pencil marks on aluminium parts may facilitate corrosion.

And Midway is selling Frankford Arsenals.........

http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=763758

Which contains  Graphite, and its even gotta 5 star rating!!

Paladin (Whut Dunno what ta do  ) UK

[El Peludo]

  Veddy Inteddestink, dis tink about graphite and al-u-miniuminumum. 

I remember noticing, years ago, that writing the rack location and phase identification on the aluminum lugs on jumper sets, with a lead pencil, as we were making them up, became a permanent mark, and was completely readable years later; it actually etched into the aluminum surface, and was not effected by weather, or normal maintenance and cleaning of the connections.  The marks could be removed, however, by a few strokes of a file or stainless steel wire brush, or the vigorous application of a coarse "ScotchBrite" pad.

A bit of real life verification of the idea.

[Delmonico]

Is there a metalugist in the house?

[Howdy Doody]

Every mold I have and that would be 6 of them is a Lee. Every one of them got the sprue plate screw pasted with Never Sieze and the pins too. Each one got a coating of the Midway release spray and I have only had to re do them a couple times for good release. I live in a real dry climate and that might be a difference. I have no rust on the steel plates or corrosion in the molds. It seems there are variables to about everything us BP shooters do, which is fine. What works for one, seems to not work for the next guy. At least we are all trying different things and that sure beats shooting smokeless factory ammo, huh?

[Paladin UK]

Fer HD........

Yehawwwwwwwww

With ya .............ALL THE WAY on that pard

Paladin (Whut kin feel the lurv ) UK

[Mason Stillwell]

Pards I cast just a few boolits.

I keep a stick of Lee's Alox lube on my bench. Every once and a while while casting I take just  a very small dap of it and apply to the underside of the sprew cutter and pivot bolt.

WOW things run nice for a LONG Time after that.

This works for me your milage might very

Mason