lubing molds

[ghostrider]

The instructions with the Lee bullet molds indicate the molds must be lubed and smoked.

Searching the internet (cause its all true on the internet) shows views at both extremes
(paraphrased):

" I've been casting for 30yrs and never lube or smoke my molds - as long as they are
clean, bullets drop right out"

"I use (stick lube/WD-40/Franford spray lube/automotive spray silicon/etc) to lube my molds"

etc, etc.

what are the opinions of the casters here?
thanks.

[SeaHawk]

Lee Precision has a video on preparation and care of their aluminum molds .

http://leeprecision.net/HelpVideos/Mold ... moking.wmv


I use just a touch of stick lube on the guide pins and sprue plate hinge for my cast iron mold as well.

[MoJo]

Well in my misspent youth I tried silicone spray on a mold - - - Those were some ugly bullets I thought that stuff would never come off. I have learned since to clean my mold with some kind of degreasing agent. I smoke or spray my mold cavities with Frankfort drop out. I only lube the hinge of the handles.

[Jumping Frog]

I've smoked my Lee 6-bangers in the past. The next time I am going to try Kroil. Castboolits has a sticky on Kroil: http://castboolits.gunloads.com/showthread.php?t=61126" onclick="window.open(this.href);return false;

It seems like all the feedback I've read on the Frankfort Arsenal stuff has been negative. Never tried it.

[MoJo]

I dug around in the shop and found an old spray can of Kroil. I treated a Lee mold and a Lyman mold after a few wrinkly bullets to heat the mold and a few more to get the excess Kroil out the molds were dropping bullets that were bright, shiny, and wrinkle free. I'm going to experiment more with Kroil and bullet casting.

[SeaHawk]

Copied from Lyman Owners Guide.

1. Bullet Moulds and Their Care

• Your bullet mould is a piece of precision equipment
  which, with care and common sense, can easily last
  a lifetime. Before using a new mould, it must be
  cleaned with a suitable solvent, such as alcohol or an
  aerosol degreaser, to remove the protective film of
  oil. Never cast bullets with oil still in the mould as
  the oil will vaporize and leave an undesirable baked
  on residue. - - - This oil must be removed each
  time before casting.

For a complete copy of the Owners Guide:
.

[Jumping Frog]

Copied from Lyman Owners Guide.

I think the people on the Castboolits forum know more about casting than the people at Lyman.

[ghostrider]

I'm going to experiment more with Kroil and bullet casting.

me too.


I tried it on one mold and it seemed to work ok.

[Gyrogearhead]

Maybe I'm just incredibly lucky but I've never had to "lube" or "smoke" the cavities in my Lee 6-banger in 45ACP. When I first got it I did thoroughly clean it and smoke the cavities and after the first 150 or so bullets went back in the melting pot for too many defects I did as my friend recommended and boilled the mould in a cook pot with a little dish washing detergent. After that I've never had a problem with the cavities filling out or the bullets sticking. Yes I do have to rap the mould "knuckle" once in awhile to get the last one to fall out but that doesn't seem to me to be a big problem. Am I the only one who doesn't lube the mould?

Curious,
Gerry

[SeaHawk]

According to all mold manufacturers the lube is to be applied only to the guide pins/V-bars and sprue plate hinge to prevent wear. If a mold is used with these areas dry excessive wear will result and the mold halves will not be in proper alignment. That will result in bullets which are out of round. Mold manufacturers do not recommend applying lube to the cavity.

Before you start a casting session, with the mold blocks cold, hold a mold half in each hand pressing them together in normal mating position then try to rotate each half back and forth in a different direction. You should not see any movement of the mold halves in relation to the other. If you see the blocks move that is the result of guide pin wear.

You can also use a micrometer to check the bullet after it is cast. Check just off each side of the seam to see if you get the same reading on both sides. All my molds new from the factory had no more that .001 offset.

Also, smoking a mold is a temporary thermal barrier which speeds up the initial casting process while an oxide layer is being deposited on the cavity from the bullet alloy . Once the alloy oxide layer is sufficiently thick to reduce wrinkling additional smoking is not necessary.

[ghostrider]

I tried a high-temp graphite aerosol lube from Home Depot and it works great.