silicone mold release, any one tried it?

[Indiana shooter]

I am restricted from saying what and how we produce our products at work but I can say we use a lot of silicone mold release spray. I talked with the boss the other day and he told me that he would give me a can for cost. ($3.50) I am tempted to try it out as a mold lube as well as a mold release. I was wondering if anyone else has used this type of stuff before? If so how'd it turn out?

[Yodogsandman]

I've seen the results, burnt deposits that just won't come off, ruining the mold. If you think you need a release agent, your mold needs polishing or other work.

[Indiana shooter]

Thanks, I was afraid that the mold temp was well above the working temp of the spray. I was just kinda curious if it would work. I don't think I have an issue with the mold releasing the boolits, one cavity falls out when I open the mold and the other requires a tap on the handle? I do have to re-smokke the mold every 80 or so boolits to keep it that way. I did try to use some polishing compound on a cotton rag but it didn't seem to make a difference.

[captaint]

Indiana - try a popsicle stick (or other softer wood object) and a magnifying glass and look at the edges of the cavities. I just rub them with the stick and look to make sure the burr is gone. It has helped many times.

[stubert]

I use dielectric silicone grease to lube my molds. seems to work good.

[MBTcustom]

First of all, bullets do not adhere to the mold blocks at all. If the bullets are sticking in the blocks it's a mechanical thing only, and while it doesn't take much to hold the bullet in the blocks, it also takes at least .002 otherwise the bullets would fall out. This can be a burr, or a cavity cut off center (more common than you might think).

Secondly, what is required for a proper mold lube is some sort of oil or grease with a very high outgasing temperature. Anything that will maintain its lubricty and constitution at the temperatures we are running will do.
I made a "sticky" out of Btroj's thread on AC oil as a mold lube, and this is what I use. 2 cycle engine oil is also a good option, or there's the old standby: Bullplate.
I don't think silicone would make a good mold lube do to its ability to outgas like crazy at relatively mild temperatures, but give it a try if you like. Put it side by side with the products I have mentioned, and see if it makes you smile or frown.

Personaly, it would have to make me smile pretty big, simply because I can get a lifetime supply of the other products mentioned for $20 from my local hardware store, or from the Bull Shop.
Not trying to discourage you, just being frank.


As a continuation of my thoughts above on mold "release" I would like to say that I put absolutely nothing, in my cavities.
I "smoked" molds for years, because that was what I was told to do, but at this point, I firmly believe that smoking the mold does absolutely nothing but act as a placebo, and possibly mask the real issue for a minute or two. In side by side tests, I have determined that a mold that sticks bullets is going to stick bullets no matter what you put in the cavities. The only differance is that your bullet quality goes down if you oil, or smoke your molds. The fact is that a properly made mold with no burrs will drop perfect bullets with squeeky clean and shiny cavities.
I consider my molds to be precision instruments and as such I put absolutely nothing in them that is not nessisary for the preservation of that precision.
Just my opinion, take it or leave it.

[docone31]

When I get "stickers" I polish the molds.
I cast a cavity through a machine screw nut. I let that cure. I remove the assembly. I do this four times per cavity.
To these I add valve lapping compound. Lightly. I take a wrench and gently turn the assembly untill it turns freely. I repeat this for all cavities. I then mix up the castings so the cavities remain consistant.
So far, so good. I have not smoked a mold since I started that.

[mongoose33]

When I get "stickers" I polish the molds.
I cast a cavity through a machine screw nut. I let that cure. I remove the assembly. I do this four times per cavity.
To these I add valve lapping compound. Lightly. I take a wrench and gently turn the assembly untill it turns freely. I repeat this for all cavities. I then mix up the castings so the cavities remain consistant.
So far, so good. I have not smoked a mold since I started that.

I find this discussion interesting as I have sticky boolits from time to time, but smoking the mold makes them drop more freely. I'd rather not have to do that.

I'm trying to visualize just what you're talking about here--you're casting boolits with a nut or bolt sticking out of them so they can be turned with a wrench? How do you "cast a cavity through a machine screw nut?" Are you pouring without the sprue plate in place? Are you placing the nut on top of the cavity opening (no sprue plate) and pouring through it such that the alloy fills the bolt opening and thus the whole assembly can be turned?

Have any pics?

[bangerjim]

I avoid "silicone" anything in all my shops. It ruins wood finishes, destroys paint applications, and in not needed in boolit mold cavities. I PC everything and silicone will prevent the powder from adhering properly, as does any grease.. I would assume HiTec would be the same way.

It has it's place in lower temp bag sealing equipment and the like to prevent plastic from sticking to the heating elements. Or mabe in a door lock.

I run silicone-free shops!

banger-j

[JonB_in_Glencoe]

Silicone spray lube works great on Foosball table rods

[docone31]

I push the sprue plate to the side, heat up the mold with the nuts in place and pour. I then let the assembly freeze prior to putting it down.
No pictures, but that is how I do that.
No more stickers.

[svr4]

If you need a release agent, the best remedy would be to check, clean and polish you molds. If you still really would like to use a release agent a trick I was taught was to use PAM cooking spray, works great and does not make your bullets come out crummy looking like spray graphite.

[Pb2au]

Sticky mold woes,,,,
1) Clean mold. Hot water and dish soap. Scrub with toothbrush.
2) Rinse.
3) Dry.
4) Get magnifying glass. Inspect each cavity for burrs along the edges of the cavities.
5) If burr, then gently flick burr off with fresh exacto blade or similar. Take care not to scratch or mar the blocks or cavities. Just lift the bur up with the tip.
6) And or, take a wooden match stick and rub gently along the edges of the cavities. This will also break away any burrs and lightly burnish the edges.
7) Lube sprue plate and guide pins. I use a micro dot of anti-seize. On the sprue plate, a dot spread across the plate to give it a haze is enough. While you are here, you might as well take the plate off, and lube the pivot point as well.
8) reassemble.
9) Melt lead alloy.
10) Cast boolits. You should need no more than a gentle shake to remove the boolits from the mold. At best they will fall out of the cavities.
11) load ammo, go shoot.
Goodsteel is correct, if your boolits are sticky in the cavities, they are being held mechanically. This is why we check diligently for burrs.
Oils in the mold cavities (this point is contested a bit) can precipitate wrinkles. Most of the time wrinkles are a result of the mold being too cool.
No loitering about while casting. Find a steady rhythm and get to casting!

[gpidaho]

I use dielectric silicone grease as a mould lube, but just on the sprue plate and guide pins. Use small amount and I get zero migration to the cavities. This has worked especially well with the Lee moulds where the sprue plate tends to gall the aluminum mould. Nothing but alloy should be put in the cavities. GP

[runfiverun]

look up lapping, leementin, or polishing.
there are a couple of stickys on the subject.

[odfairfaxsub]

Silicone spray lube works great on Foosball table rods

Lol classic!!!

[milrifle]

For those who polish their cavities using the 'nut' method: Is this just on steel molds? Would a steel nut not tend to mar the upper surface of an aluminum mold?

[mdi]

I have always been of the opinion (much better expressed by Goodsteel) that lead does not stick to aluminum and usually needs some type of flux to stick to steel. So, if a bullet sticks in a mold, something other than metal to metal adhesion is taking place. I routinely use a lap(made from a cast bullet) and a Comet/oil paste to clean new or sticky molds. I think I smoked a mold mebbe 15 years ago but didn't like the carbon deposits on the first few bullets cast after smoking. My mold "release" is nada, zip, nothing...

[Fishman]

For those who polish their cavities using the 'nut' method: Is this just on steel molds? Would a steel nut not tend to mar the upper surface of an aluminum mold?

The nut should not contact the mould in any way

[country gent]

I have reworked moulds for several here and "polished" some of mine lightly also when needed. I take 2 pices of wood and drill a small hole to hold a bullet between them A pice of cardboard between allows clamping force. Place a bullet in them in a vise and drill a hole in the base as deep an the driving bands or so you dont want to break thru the nose. 1/8" or 3/16" work good. Glue the snug fitting pin in place in the bullet. For sticky moulds I just use Simichrome or flitz to lapp or polish here. Lightly coat a bullet with one of these and fit into mound cloaing carefully and clamping in a small vise lightly. with a t tap handle work the bullet back and forth 3-5 times 1/2 turn (approximate) rotate forward 1/4 turn and work back and forth 3-5 times do this thru a full rotation or two. check and see if finish is improved a single small drop of light oil helps to improve polish effect and finish. Keep in mind that .001 removed makes for .002 on bullet dia. A rough machine finish, chatter, can also cause the mechanical lock. Square lube grooves and shoulders also make a bullet harder to get to release at times. SOme desighns drop much easier than others due to this. Lube grooves with a angle to then or radious drop better than deep sqyaure grooves as a it opens to release with the angles. The light [polishing of the cavities and burr removal ussually help alot. There isnt alot that can be done for off center cavities unless they are undersized also.