A Trick I Use When Lubing Moulds

[Josh Smith]

Hello,

I do not know if I'm the first to do this, so I'll post it here. I can find no other reference to it.

Having grown tired of working to get my moulds to heat evenly and quickly, I decided a few weeks ago to try a different lube -- namely, heatsink grease -- on my moulds.

Radio Shack has some very awesome silver-based heatsink grease that is advertised as not having mercury in it (though if the mercury-based grease was all I could find, I would use it).

After applying a bit to the pins and the area under the sprue cutter, as well as putting a small spot wherever there was ample room to do so without risking contamination of the mould cavities, I found that I was able to cast longer and at a wider range of temperatures, both with pure lead and with alloy, without frosting or wrinkling.

If it doesn't work for you, the stuff is easily removed, as well!

Josh

[Catshooter]

Really. Now that is interesting. I may have to pay attention to that, thanks.


Cat

[MtGun44]

Bull Plate lube has the problem totally under control for me. The heat sink lube that
I have used was the messiest stuff in the world, getting on EVERYTHING. I hope yours
is more friendly.

Bill

[462]

In an earlier career, I used a lot of heat sink compound and it was extremely messy.

Joshua, I'm glad that whatever it is that you've found works for you, however, like MtGun44, I'll stay with Bullplate.

[onondaga]

Josh,
I use Navagard G624 Silicone Compuond, a silicone dielectric grease. Meets Mil Spec 5-8660C. It is clear and about the viscosity of Vaseline. MSDS says Dimethylpolysiloxane. That is pure silicone. This works great, no discoloring. I apply it with a small cheap flux brush that I have shortened the bristles to 1/4 inch, and just brush out the littlest bit to a shine.

The Shack also has a clear silicone dielectric grease, I'm sure it would work fine.

Gary

[runfiverun]

bet it's the same dielectric compound that comes with new electronic parts for car distributors.

[cavalrymedic]

Ok. noob question. What is Bullplate lube? Two of ya are swearing by it. I'll try anything that works.

[MtGun44]

Go to the Bull Shop, link at the bottom of the page. Dan is a member and sells little bottles
that will last a lifetime IF YOU DON'T SPILL IT! Many do something special to ensure that
they don't knock over the little bottle. Tiniest amount on a Q-tip with excess squeezed back
into the bottle against the neck. Coat the top of the mold, underside of sprue plate and
alignment features of the mold, keep out of cavities. Excellent stuff.

OOPS! The Bullshop link isn't there any more! Go here: http://bullshop.gunloads.com/

Bill

[Josh Smith]

Hi Folks,

Dielectric grease is non-conductive grease used to prevent corrosion between electrical connectors.

Heatsink compound is totally different. If you have a solid state component (say, a computer chip or a ignition control module) that heats up quite a bit when working (I'm running 50c on Core 1 and 45c on Core 2 of my computer, for example -- halfway to boiling), you're most likely going to have a heatsink on it.

The heatsink and the solid state component do not have perfectly flat surfaces, so heatsink grease (or compound, however you want to call it) is used between the mating surfaces.

This is basically just a thick lithium grease with silver or mercury suspended in it. This allows the heat to be more effectively transferred between the solid-state component and the heatsink, thereby extending the life of the component.

Now, in a leap of logical experimentation, I thought that perhaps, instead of having the mould block heat up as separate components as they often do (especially the sprue cutter), if I were to dab some heatsink compound onto each surface which did not mate flat (lots of them as air must escape), then I could make the whole block heat up as one unit, more uniformly.

It worked.

That's the entire point behind using the heatsink grease/compound/whatever. :)

Josh

[mooman76]

I was being extra careful so I wouldn't spill mine but.... I didn't secure the cap one day and went to pick it up by the cap and over it went. I finally found a new cap for it. A lid with a top that snaps shut and only has a small hole in the top. That's the best way to keep from spilling, for me anyway.

[geargnasher]

bet it's the same dielectric compound that comes with new electronic parts for car distributors.

Nope. The compound to which you refer contains dimethylpoly (or polydimethyl, which ever you prefer)-siloxane oil about the consistency of light grease, and fumed silica. Fumed silica is a thickener, in fact it is often used to thicken soft-serve ice cream and milkshakes. It acts as a carrier for the silicone oil in applications where a viscous "grease" is needed, like for non-wicking dielectric and brake slide grease.

Personally, I'm totally with Gary on this one for aluminum moulds. I finally bought a case of Sprayway Instant Spray #936 (pure, "wet" silicone spray) for lubing my aluminum moulds since I kept using one can up on other things like door locks, hinges, weatherstrip and such (no staining residue like WD-40 or other petroleum sprays). I tried this a couple of years ago after getting tired of the tobacco-juice stains Bullplate left on my nice aluminum blocks, and I feel the correct silicone oil/grease is actually better for the aluminum moulds. Bullplate is invaluble for casting with any other moulds, though, expecially brass and iron, and for lubing taps and moving parts on bottom pour furnaces.

Gear

[runfiverun]

amazing whats in foods as binding agents and such.
propylene glycol, used in food is also used as an antifreeze in fire suppression systems.
and now silica [yeah,yeah i know silica is one of the most common substances on earth but still]
i mainly use aluminum antisieze on the few aluminum molds i have but i have tried bullplate on them also.
gonna have to keep an eye out for the silicon spray now.

[Tag]

Nope. The compound to which you refer contains dimethylpoly (or polydimethyl, which ever you prefer)-siloxane oil about the consistency of light grease, and fumed silica. Fumed silica is a thickener, in fact it is often used to thicken soft-serve ice cream and milkshakes. It acts as a carrier for the silicone oil in applications where a viscous "grease" is needed, like for non-wicking dielectric and brake slide grease.

Personally, I'm totally with Gary on this one for aluminum moulds. I finally bought a case of Sprayway Instant Spray #936 (pure, "wet" silicone spray) for lubing my aluminum moulds since I kept using one can up on other things like door locks, hinges, weatherstrip and such (no staining residue like WD-40 or other petroleum sprays). I tried this a couple of years ago after getting tired of the tobacco-juice stains Bullplate left on my nice aluminum blocks, and I feel the correct silicone oil/grease is actually better for the aluminum moulds. Bullplate is invaluble for casting with any other moulds, though, expecially brass and iron, and for lubing taps and moving parts on bottom pour furnaces.

Gear
Do you spray the entire mold or just sprue plate, hinge and pins and will any silicone lubricant work, mine is JOHNSEN'S multi-purpose (VOC compliant) what ever that means

[onondaga]

I wouldn't spray the whole thing. Spray a Q-Tip and rub it where you want it.

Gary

[mtgrs737]

Ah those trickly little round bottom bottles of bull plate, many here have fallen victim to them, myself included. Bullplate is a product that makes our hobby much more enjoyable and for that reason I will tell you all just what it really is....



Scroll down to see...















Bullplate is:


















Magic!!!! But don't tell anyone I told you!!

[JIMinPHX]

I was able to cast longer and at a wider range of temperatures, both with pure lead and with alloy, without frosting or wrinkling.


You say that using this type of lube prevents frosting???? That doesn't make sense to me. How did you test the correlation?

[Josh Smith]

I said it seems to help cast over a wider range without wrinkling or frosting.

I usually cast balls at a setting #3. After ten fill/cut/dump cycles with alloy, I start frosting. If I go lower than 3, it starts wrinkling, and higher, it starts frosting sooner.

After applying the grease, I could go down to setting 2 and up to setting 5. Just gave me more room for error.

I tried this with four moulds (.490", two .440", and one dual cavity aluminum 230gn TC .452"). In all instances the moulds were preheated.

It makes sense if you think about it. Let's say you preheat the mould (no heat transfer grease) by dipping the corner into the pot. that side heats up faster than the other side of the block and the sprue plate is colder than either.

Even if you use a plate to preheat the mould, you're still going to get a temp difference between the mould and the sprue plate.

Now, if you use the heat transfer grease on the lube points and on points between the cavities and on top of the mould block between the blocks and the sprue plate, it will transfer the heat more evenly between everything, just as it transfers heat more evenly from your computer's CPU to heatsink.

All I can say is to test it for yourself. You may not notice a difference. I did. My previous lube was Permatex Anti-Seize, if that matters to you.

If it doesn't seem to work for you, it's easy to wash off. If it does work for you, it sticks better than anything I've found.

If you'd like to try it, the tube is worth the $7 or so just to have around, anyway. It comes in handy for other things as well.

Josh

[JIMinPHX]

You're saying that the grease helps to transfer heat between the sprue plate & the blocks. OK, that makes sense to me. I can see where that might make a difference. Thanks for explaining the point that I missed.

[geargnasher]

Do you spray the entire mold or just sprue plate, hinge and pins and will any silicone lubricant work, mine is JOHNSEN'S multi-purpose (VOC compliant) what ever that means

Like Gary said, saturate a Q-tip with the spray and wipe it where you want lube. I don't know about Johnsen's lube, but make sure it isn't "dry" silicone spray.

Gear

[Catshooter]

That makes alot of sense Joshua (about the heat transfer).

You do know that a frosted boolit is not a bad thing, right? Frosting is merely a function of lead temp and has no effects that we care about.


Cat

[Catshooter]

Joshua,

I went to Radio Shack today. Yikes! $9.99 for a tube of about 1/1,000th of an ounce! 'Course, the price of silver just might have something to do with that.

Anyway, I bought a tube and will give it a shot, thanks. I too have noticed uneven heating during the pre-heat. All of my iron moulds produce really well, once they're evenly heated. That can take a while. This just may help.


Cat

[Slingshot]

Ok curious question.

I have 3 bottles of lube that I got when I bought group buy molds from Miha. I have never used bullplate so forgive the ignorance, is this the same stuff ? Or different? :veryconfu

Jeff / Slingshot

[degruix]

Many thanks for posting this.

I have been looking for a better sprue lube and will give the heatsink grease and the dielectric grease a try. I am also going to try some antiseize compound.

[Catshooter]

Sling,

Different. Bullshop's lube is a lube, and intended as such.

This is primarily a heat transfer agent. Idea being to help increase and even out the transfer of heat, particularly during pre-heating a mould.


Cat

[justingrosche]

I use Bullplate exclusively. It works so well I haven't pursued any thing else. One thing that I do to keep from spilling the BP bottle is apply a drop of lube to a half dozen q-tips at once and have them with in reach while casting. When I need to reapply I'm not fumbling for a bottle.

[Slingshot]

Thanks for the Reply Catshooter. I will be ordering some Bullplate soon then.

Jeff / Slingshot

[FWest]

This is an area I do know about. Thermal paste or thermal compound. Many kinds are made, here is a review. It will serve as a list more than anything.
I have a few different types and never thought to try them for casting.
http://www.xbitlabs.com/articles/coolers/display/thermal-interface-roundup-1_12.html#sect0

[degruix]

justingrosche

I use Bullplate exclusively. It works so well I haven't pursued any thing else. One thing that I do to keep from spilling the BP bottle is apply a drop of lube to a half dozen q-tips at once and have them with in reach while casting. When I need to reapply I'm not fumbling for a bottle.

How often do you have to reapply?

[justingrosche]

I re apply once I find that the sprue plate is starting to take a bit more effort or the plate is dragging across the top of the mold.
If I had to put a number of casts to it, I'd say 200 or so, depending on the mold.
When they say a little goes a long way, they ain't kidding.

[John Boy]

I was able to cast longer and at a wider range of temperatures, both with pure lead and with alloy, without frosting or wrinkling.How does lubing mould pins control or aid the temperature of the melt - as a factor of how cold or hot the mould is? Or what am I missing?

[tomf52]

I have been using synthetic gear oil, applied sparingly with a q-tip to the pins, hinges, and sprue surfaces to work just fine. Cheap too!

[cajun shooter]

Bullplate is by leaps and bounds ahead of the next product for all moulds. It works so well that you only have to use a q-tip to apply. As I posted sometime back for all the new users, when ordering always order more than one so that you may show others how well it works and you can replace the bottle you spill on your bench. To stop the spills, I bored a bottle sized hole in a piece of 2x6 or 2x4 and place the bottle inside of it. Leave it there until replacing and you won't be buying more because of spills. If you are a smokeless powder shooter then Bullplate makes a easy to use lube when mixed with beeswax. It's easy and fast. The beeswax may be purchased from Randy Rat.

[Josh Smith]

How does lubing mould pins control or aid the temperature of the melt - as a factor of how cold or hot the mould is? Or what am I missing?

Evenly heating the mould, including the sprue plate, leads to consistency.

If you use thermal conductive grease for lube, it helps with even heating.

Josh