Mine is a lee pot and temp varies all over the place but I generally shoot for around 725 depending on alloy and how much metal is left in it.  The main thing that helps me is to scrub the mold cavity clean with Dawn and a toothbrush then spray with brake cleaner and dry.  To maintain mold temp I lay the mold down on a hotplate  while cutting sprue and and emptying the mold. Sometimes you can leave the mold on top of the pot or even dipped in it but the plate works for me so far.  Plus I don't have to worry about my bumbling hands knocking the mold off and showering everything down with lead.  You might drift over to the Cast Boolit forum and see what some of those guys say.

Quote:

* Mold on stove gas burner to heat up
* Thermometer in pot - bring temperature to 730 degrees
* Ladle pour: 5 second pour and 5-8 seconds for the sprue puddle to frost

I also don't have an Accurate aluminum mold, but have several other brands in aluminum. I keep the temps up, but I also keep the casting process going pretty quick. If I stop to sort or do anything else, I simply knock the sprue off, but leave the bullet in the mold, so it keeps it hot. Then drop the bullet and continue casting. Unless I stop for a very long time, leaving the bullet in the mold has always been enough to keep the mold warm.

What's working for me (finally) is to get the mold too hot and then let it cool by casting. With the aluminum it only takes 2-3 bullets to get it down to the proper casting temp. Then cast as quickly as I can to keep it hot. The biggest problem is the sprue-plate will overheat and the puddle takes a while to 'frost'.

What was interesting to me is how big a heat-sink the aluminum mold is. I set my molds in the edge of the pot with the handle going across, above the melt, to the other side. I usually let the bottom edge of the mold nearest the center of the melt just touch or stay just above the melt. With the aluminum mold when it was just touching the melt I couldn't get the melt temp above 745F. Too much heat loss radiating through the alumium mold blocks. I raised the blocks about 1/32" above the melt and the pot returned to my normal casting temp of 775F in fairly short order.

Lee Magnum 20#. Easily goes to 825F (hottest I've had it). It was easy to see how well the aluminum was transferring the heat as the sprue-plate turned a tempered blue.

I have only owned one aluminum mould in the past 16 years and all though cheap I could not use it or give it away! I have since learned how to make my own blocks and cut my own moulds to what ever my little heart desires. This is one of five I recently cut for my 28-35SS that I have yet to try and I only do this for myself and very close friends for the sake of learning and sharing what one cannot readily buy for a 12 Twist.

(You need to Login or Register to view media files and links)

JLouis

Glenn,  You said it before I could volunteer my experience: "What's working for me (finally) is to get the mold too hot and then let it cool by casting. With the aluminum it only takes 2-3 bullets to get it down to the proper casting temp. Then cast as quickly as I can to keep it hot. The biggest problem is the sprue-plate will overheat and the puddle takes a while to 'frost'".   That's about what I've found.   

I've still got maybe five Accurates and sold two after getting rid of my 45Colt.   I'll keep all but a 45-70 I'm gonna sell but that sprue is a problem I've not conquered yet.  Smear or tear.  Heck of a choice!  If you get that one figured please shoot me a PM.  I've done just about everything every one has ever offered.   I get good cuts but way to many of the other!   And that Sprue will gauld the snot out of your mold (and sprue plate) if you don't use something like Frankford spray between the too surfaces.   If you don't count the sprue dimples & pimples the weight comes with a decent spread.   Also, if you adjust your sprue keeper and the sprue plate bolt, be sure to back the keeper out all the way first and ensure there is a brass cushion under it.  The last two I ordered did not though Tom said they did.   Good way to bugger the threads fast.     He drills a good hole and they drop from it nice, you can say that much for sure.   Used to think I liked them better but that was then and I hadn't used good steel moulds yet, nor my LBTs.   Just got my first brass mould so that will be a new experience.  Course I've still got a lot to learn compared to you fellows.