Notes on smoking molds: I have about 20 Lee molds, so do have some experience with these things. With Lee aluminum molds I have used them bare, smoked them with wooden matches and used Frankfort Arsenal's "Dropout" graphite spray, as well as a spray graphite lubrication product made for locksmithing. First off, the locksmiths' product was terrible. I assume it is a good lube for locks, but was dirty, gummy and worse than useless for molds.
* Using them bare works sometimes, especially after they are "seasoned" and have a bit of use on them. Bullets tend to stick when they are new, but after a few casting sessions they get better. I suspect that this is because the heat creates microscopic carbon particles embedded in the mold's metal, but that's just a guess.
* Dropout graphite spray works fine, but small patches of it tend to flake off with use if you apply it heavily. When you respray it - just like spray paint - it doesn't evenly fill the spot, but leaves a little uneven crater. Eventually I find myself cleaning the mold of the old spray to even things out. My advice is to spray it as lightly as possible. It's a good product, but IMHO only if you barely mist it on.
* Wooden matches work fine and are extremely inexpensive. Every once in a while I re-smoke the molds, but this is seldom required. Matches are probably the best method of the three. Again, smoking seems to be required less frequently as the mold ages and is used.
Last word: In our southern heat and humidity aluminum molds do tend to corrode over time, if left unattended. My casting station is in an unheated CONEX box, so I bring my molds back into the house after use. I have a few oddball molds that I rarely use. These, despite Lee's warnings, do get lightly oiled before I put them away. I spray them with brake cleaner and wipe them clean before casting again. Other than a bit of stink when I first pour, the remaining oil doesn't seem to damage anything.
Best regards
Doc
