Heating Mould

RPM · Post by **RPM** » Wed Dec 17, 2003 2:48 pm

What is the best way to heat up the mould before beginning to cast bulets?

Lee Stone · Post by **Lee Stone** » Wed Dec 17, 2003 3:08 pm

RPM

I use a Waage 25 pound pot that has a heating shelf on it. My Lyman 20 pound pot also has a heating shelf but it doesn't seem to be as efficient as the one on my Waage. Anyway, I set the mould on the shelf while the pot itself is coming up to temp. Then I bring the mould fully up to working temp. by casting and putting the rejects back into the pot untill good bullets start coming out of the mould. I have on occasion heated a mould by dipping a corner of it into the melt. But the shelf on my Waage seems to be efficent enough to keep the mould up to temp. once I have gotten it there.

I know that some preheat their mould over their gas burner if that is the type of heat source the are using. And I have heard some describe heating the mould on an electric coil element. I do not do this. I am a genuine born-again klutz. If I preheated my moulds like that I am certain I would end up warping them. But some people do it quite well from what I understand. I play it safe.

LJBass · Post by **LJBass** » Wed Dec 17, 2003 6:05 pm

RPM,
As Lee said there are at least a couple of ways to preheat a mold and ladle. What I have found most effective is a good electric hotplate. I have used one for the last 2 years. If you experiment with the heat setting a little bit you can find the point where your first bullet cast is a keeper and you don't have to cast 5 or 6 to get the mold up to temperature. If you do have to cast that many to get your mold right I would suggest you don't throw the rejects back into the pot until the casting session is over. Throwing 5 or 6 heavy bullets back into a stabalized melt is not conducive to a close tolerance casting session. I will generally cast 60 or 70 533 grn .45" bullets per pot and the only rejects will be those that got nicked or dented leaving the mold.
Good luck,
LJ

MRich · Post by **MRich** » Thu Dec 18, 2003 5:57 am

RPM:

I use a single element hot plate with a steel plate on the element and then the mould on that. I turn on both the lead pot and hot plate at the same time and the mould is up to temperature when the lead is ready.

MRich

Vbull · Post by **Vbull** » Thu Dec 18, 2003 6:09 am

RPM,
I don't know if this is the "best" way, but it works for me. I use a propane torch and slowly warm up the mold when the lead pot is up to temperature. I purchased a used non-contact IR thermometer off ebay a few years ago and check the molds temperature with it. When it reaches 250 - 270, it's ready to start pouring. Good bullets start dropping soon after. It does depend on what mold I'm using. The heavier SAECO / Jones molds need to be a bit hotter then the lighter Lyman molds.
I also set my lead pot up with an electronic temperature controller with a thermocouple immersed into the lead by the outflow valve. It maintains my lead temperature to +/- 5 degrees (normally closer on the digital readout). Makes for easy casting sessions. I also bottom pour from an RCBS pot, which is not supposed to work if you listen to the conventional wisdom on casting match grade bullets for our sport. Good luck, Frank Monikowski

Lee Stone · Post by **Lee Stone** » Thu Dec 18, 2003 8:53 am

LJ and MRich, I appreciate the idea of a hotplate with a steel plate on top of the element. That would be completely adjustable and the the mould would not have to ever come in direct contact with the element. Think I'll start looking around for a small hotplate.

By the way, when I said I put the rejects back into the melt, I meant at the end of the casting session, or else I wait for the melt to re-stabilize temperature. Solid alloy put into the melt is going to lower the temperature of the melt, so one needs to let the melt come back up to temp. On my Waage, I have found that the heating shelf it has will keep the mould at casting temp during a wait time like that and resumption of pouring will result in good bullets. The heating shelf on my Lyman doesn't seem to be able to keep it up to temp as efficiently.

Frank · Post by **Frank** » Thu Dec 18, 2003 6:31 pm

For years I have just rest the body of the mould in the pot with the mould a little over half way in the hot lead. When the lead gets up to temp I start casting. The mould I have been using is a Paul Jones and still cast perfect bullets. I weigh each bullet and any thing + or - .5gr goes back in the pot.
Frank Costa

flintski · Post by **flintski** » Thu Dec 18, 2003 7:19 pm

You got to remember how old I am, but do you remember years back when we had engine block heaters, the type that was magnetized to stick on your engine block so it wouldn't freeze up over night. Well, that is the best darn thing since plastic money. Turn it on stick the mold on it and when you are ready so is the mold. If you have to go the potty and check what's on TV, you can start with a perfect bullet...That's my story on I'm sticking to it. :D

Omaha Poke · Post by **Omaha Poke** » Thu Dec 18, 2003 9:04 pm

Frank, that is basically what I do. I always make sure my lead pot is full before shutting it off for this past casting session. When the alloy has cooled enough to be firm, I then put my ladle on top, and the next time I go to cast, I put my mould on top of the solid lead. By the time the lead heats up to be molten, the mould is hot and I have maybe 4-5 bullets that aren't filled out. They go back into the pot the next time I add alloy.

I use a propane plumbers pot most of the time, so you want to make sure that the handles are not going to get burned by the propane flames. It is not a problem with the Saeco handles with their long shanks, but if using Lyman handles beware!! I have scorched a couple.