PDA

View Full Version : Dry graphite film on mold surfaces: A panacea?



Maven
07-16-2005, 05:00 PM
I've been experimenting with dry graphite film, specifically NAPA's "DGF 123" for several months and am quite impressed with it. At first I just used it on top of the mold blocks and on both sides of the sprue plate instead of a soft pencil or graphite stick (available in art supply stores). Lately though, I've been spraying the mold cavities themselves, mostly to determine whether it works better than smoking them with a wooden match. I'm happy to report that it's fast, effective and can be applied to a hot or cold mold. E.g., I have several molds that can take as many as 1 doz. casts, sometimes more, before they drop perfect bullets. Re-smoking them helps, but dry graphite film cures them at once. Just the other day I was casting with my Buckshot-designed 8mm Lee mold and found small areas of poor fill-out on the nose in spite of correct temperature and a smoked (and resmoked) cavity. Spraying the hot cavity with DGF 123 cured the problem. As a final example. I traded TXBirdman for a new RCBS mold and figured after degreasing it, I'd try it on both [unsmoked] cavities, which I did. Voila! It dropped perfect bullets with no sticking at all. So far as I can tell, it doesn't wear off the cavities with use, but the sprue plate and mold top surfaces are a different story. I'm also hoping that it inhibits rust on iron molds as well. The NAPA brand comes in an alcohol carrier so it dries quickly. Almost forgot: I coat my lead dipper (ladle) and top & inner surfaces of my Lee furnace with it after I clean them to control the build-up of oxides. It works to a degree, more on the dipper than the inner lining of the furnace.

Magnum Mike
07-16-2005, 05:59 PM
I recently purchased the Midway branded product that i believe is also a spray graphite ( http://www.midwayusa.com/eproductpage.exe/showproduct?saleitemid=763758 ). I tried it first on a mold that really gave me no issues and it worked great. The boolits do have a matte looking finish but i figger all the better to hold the lube! ;) Seein' how well it worked i decided to try it on a couple of molds that in the past have been difficult to achieve complete fill out, the results were EXCELLENT!!

As noted, i am experiencing the same traits of it not wearing off in the cavity and the mold faces but it does need to be reapplied on the top of the mold and under the spure plate, no biggie! Thus far i find this product to be well worth the purchase price and a must have for "difficult" molds. ;)

BruceB
07-16-2005, 06:12 PM
Four or five years back, I'd estimate, I tried a can of Midway's "Drop Out" spray. It worked very well in many situations.

When that can ran out, it was at an awkward time and I NEEDED some more "right now". I went to our local Victory auto-parts store and bought a BIG can of spray graphite for about 1/2 the cost of the Midway stuff...and got THREE TIMES the quantity for that half-price figure. That can has lasted me about two years to date, and is still well over half full. It's a bargain.

In fairness to Midway, just the packaging of a low-cost product like this probably costs a good bit more than the contents, so I don't hold it against them.

I don't use the spray on every single mould, by any means, but it certainly is useful in a lot of cases.

onceabull
07-16-2005, 07:18 PM
BruceB: Good to know that you will have "treatment" on hand should that new to you 30 caliber mould require sweetning.!! Congrats, Onceabull

Johnch
07-16-2005, 10:46 PM
Sounds great ,I will have to try it .

One thing , how thick dose it go on ?
Have you micked a bullet that was droped with and with out the spray ??
I have several molds that I use the bullets as cast .
I just pan lube them

Johnch

JohnH
07-18-2005, 11:21 PM
What I found with the Midway product, and I suspect this may be true of all spray grafite, is that I lost abut .001" of bullet diameter. Stuff does work great on the sprue plate and mold top, and the bulelts will literally fall out. I'd be curious to hear what results you are getting in respect to bullet diameter.

Leftoverdj
07-19-2005, 12:18 AM
John, my experience is the same as yours. Graphiting the cavities costs a thou or more of diameter. Applied to the top of the mould and the bottom of the sprue plate, it stops galling cold.

NVcurmudgeon
07-19-2005, 12:24 AM
This place is a post-graduate school of cast boolit education. Lead pencils are good, art supply store graphite sticks are better, and I can't wait to try DGF 123.

sundog
07-19-2005, 09:07 AM
I'm a Midway Drop Out user. After cleaning a mould I spray it all over as a rust preventative which does a pretty good job. For the block faces and cavitities though, before ever casting session I clean them with a bronze 'tooth brush' paying particiular attention to vent lines and lube groove recesses. Then, instead of applying the spray directly to the mould, I saturate (just a squirt or two) a Q-Tip and then apply like I was painting it. No issues with loosing diameter, matte finishes, or anything like that. Does not work well if the mould is hot though.

I've also done the lead pencil thingy. One thing I found that when doing that is ocassionally you can 'feel' a burr that you can't see and missed earlier.

Even with a good quality mould, all of this only enhances the experience. sundog

edit: Oh, forgot to mention that I'm going to try the NAPA product as I'm cheap. Three times more for half the price? Kinda like burning surplus powders....

shooter575
07-19-2005, 10:54 AM
I used Rapine mold prep for years.It seem to work a bit better than the NEI stuff. Anyway I figured out it was just alochol and graphite and a ball bearing. My shop supplyer from work {Drummond American} has a product called Slide. Seems to be the same stuff in a spray bomb. It is all I use now. I cast a lot of HB minnes and the base pin does give problems sometimes.This lets em fall off. You can spray on a hot mould also. Boolet size reduction is very minimal
Hey the rep gave me a couple cans so the price is right!
BTW I think they changed the name of that stuff to "Free Ride" Drummond likes dumb names for their products?

floodgate
07-19-2005, 11:38 AM
Kano Labs (the Kroil folks) offer something called "Penephite" in a spray can that sounds like something similar. I don't have any now, but next time I get one of their sampler offers (about once a month) I'll get a can and report on it. BTW, they have a super penetrant called "Silikroil" that is even better than the original Kroil; but I'd worry about the silicone film it leaves - it's a beast to remove if you're going to paint, and might give problems in a rifled bore. floodgate

Jumptrap
07-19-2005, 11:58 AM
DGF?

I had a girlfriend that was one of those, never thought of using it on a bullet mold though.....seems like a terrible waste.

drinks
07-19-2005, 05:59 PM
I have found the Midway spray works good, I do remove it off the vents with a Q-Tip and acetone, this has the side benefit that I can then take a magnifying glass and look for any filaments of the Q-Tip that have snagged on a burr, a slight tough with an Exacto knife takes care of the burr fast.
Don

beagle
07-19-2005, 09:23 PM
Several of us have been doing the same process with spray moly lube.

After drying, it's polished out with a soft pointed wooden stick. This is felix's old method and really works well. Once done, it doesn't need to be redone in the cavities.

The sprue plate and mould top need to be redone after every casting session but that's just a spray job and no burnishing with the stick.

I even moly the outer surfaces and have had no surface rust problems in years.

I'm about out of the moly and I'll give the graphite a good try. Could be it can be burnished in the same manner as moly and we'll not suffer a diameter decrease./beagle

RayinNH
07-19-2005, 10:09 PM
I've used the Midway product with good results. As a side benefit, when your done casting, spraying the mold blocks with the graphite seems to protect them against rust. When you begin casting for the next session an old toothbrush will take off the excess graphite that was put on as a preservative...Ray

Crowkiller
07-24-2005, 02:18 PM
Mavin, you just solved a big problem of mine. I have a Lee 310 grain rnfp mold I've had a devil of a time with. My casting sessions have left me with about 80% rejects. This has been from "shrunken bullet syndrome", where a small area on the shank is frosty and undersized. I tried high heat, low heat, bottom pour, ladel, wheelweights, range scrap, wheelweights with tin, and many combinations of the above. I tried the DGF 123, and now have about 30% rejects using my "range scrap" (I sorted out just the big cast bullets, it runs a little harder than WW from my unscientific hammer tests).
I have one more problem mold to try it on, but so far, so good.

Maven
07-24-2005, 06:49 PM
Crowkiller, Glad to hear that it solved your mold's problem. I had the same problem with a Lee .38cal. 2 cavity wadcutter mold. Had I known about DGF 123 then I wouldn't have tossed it!

boogerred
07-26-2005, 12:42 AM
i never thought of the reduced sizing idea. if i squirt a 45 mold enough will it make 32 cal bullets? ive been using a product called lok eze with good results as far as bullet fill-out and drop out but never thought about the diameter. this stuff is an aerosol with a lot of blast and a little deposit that leaves a black film

Lee W
07-26-2005, 04:41 PM
Alright, How many people had to look up panacea :?: