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kenny1
10-08-2008, 10:22 PM
How do you know when your mold is getting to hot and to switch over to another to let it cool

Jon K
10-08-2008, 10:31 PM
It will frost real bad, a won't fill out leaving a gas pocket(void).

Jon

dardascastbullets
10-08-2008, 10:40 PM
How do you know when your mold is getting to hot and to switch over to another to let it cool

I will add to the other poster that your sprue plate will begin to gouge out metal rather than make a smooth shiny cut. This is typical no matter what the content of the alloy.

docone31
10-08-2008, 10:47 PM
I second smearing the sprue.
I start slowing down when the sprue takes much longer to freeze than usual.
I find, when that starts happening, the sprue starts smearing rather than seperating cleanly.
Another indicator,
When you pop off the sprue and dump it into the pot, the casting flows with it.
When that happens, I take a break for a bit.

John Boy
10-10-2008, 02:58 AM
How do you know when your mold is getting to hot and to switch over to another to let it cool
Kenny - not necessary to switch over to another mold. Keep the temperature of your melt within a 10 degree variance - your rhythm steady using The Eight Phase Casting Cycle ... http://www.longrangebpcr.com/8Phases.htm

chewie
10-10-2008, 11:26 AM
:coffee:i am learning everytime i read on this site. i got to get a BASIC book to learn properly. going to the valley maybe next week to look for one.

Le Loup Solitaire
10-10-2008, 09:10 PM
When the mold gets too hot, the sprue starts to take longer and longer to set up/harden. One of the signs that it has done so is seen as the color of the puddle goes from more shiney to a dull/er gray. If that doesn't happen and you attempt to knock the plate around you will get some or all of the problems previously mentioned by other forum respondents. The biggest nuisance of all is the lead smears on the underside of the cutter and across the tops of the blocks. These have to be removed or else they continue to build up and "unsquare" bullet bases and/or ragged holes will result. There are several ways to remove the smears; the one I have used is to rub the smear, preferably when hot, with the corner of an ingot. That seems to absorb the smear. Overly hot melt/blocks usually produce frosted bullets as well. They don't shoot any differently than regular bullets, but some folks don't like the way they look. A way out of that (if you like extra work) is to shine them with #0000 steel wool. To avoid the overheating, you can A)lower the melt temp, B) use another mold in tandem with the first which (doesn't eliminate the frosting) allows the first mold sprue time to harden, C) develop a rythm of counting to 5-8 (seconds) which should be ample time for the sprue to set up. D) Fold a few layers of cloth and put them in a shallow dish of water. Toulching the bottom of the blocks (or the top of the sprue and puddle when it has hardened) to the wet/damp cloth will lower the temp of the mold and its bullet. All this really isn't necessary if the proper temp range is kept to start with. Not always so easy! Molds with large caliber bullets tend to overheat anyway after a while even with the right temp and rythm, so the situation occurs "in the best of families". A casting thermometer helps to some extent, but "sprue watching" is constantly a part of the game. Its not so critical with medium size bullet molds, but nevertheless it still needs watching. But knowing the signs and the options is definitely a part of successful casting. I hope that this has helped you. LLS

Dennis Eugene
10-10-2008, 09:24 PM
I hope I never get to the point where I'm pollishing my boolits with steel wool or anything else for that matter. lol Dennis

HeavyMetal
10-10-2008, 11:23 PM
If you cast with two identical molds the overheating part should never happen, your rythem should be the factor that controls mold temperature, not the alloy in the pot, with the understanding, of course, that the alloy has to be at the correct temp to flow smoothly!

missionary5155
10-11-2008, 06:29 AM
EXPERIMENT ! I sometimes am running 3 molds at a time (usually single cavity) but I always have the next mold in line ready to cast... and sometimes I loose track which mold is "UP" to get filled.. But I just want to produce good boolits.. I tend to turn up the heat and keep it hot. My little propane table top cooker has plenty of heat and I just keep adding the metal andf check the thermometer when the radiated heat seems a bit high.

Jon K
10-11-2008, 06:45 AM
Bullplate Sprue Lube...................for the smears, ...........and Bruce B's speed casting method to keep the mould heat under control. Get a thermometer and figure what temp you like working with the best for that mould, not all moulds will run smoothly at the same temp. Write it down, and refer to it next time.

Jon