Cooling Sprue cutter

[ohman11]

I was looking at Goatlips page and he cools the sprue before cutting it. What do you achieve by doing this?

[dk17hmr]

Cool the spur down faster.

I when I am going at it fast and my mold is starting the over heat I cool the spur plate on a damp towel and go back at it.

[ohman11]

Cool the spur down faster.

I when I am going at it fast and my mold is starting the over heat I cool the spur plate on a damp towel and go back at it.

Do you do this on 2 cavity molds too?

[Le Loup Solitaire]

Hi, Welcome to the Forum and "the sickness".When melt temps are high, and/or the caster is going fast and /or the mold is for a larger caliber, the blocks will overheat. Knocking the cutter around before the sprue has hardened will invariably result in lead smears across the top of the blocks and on the underside of the sprue cutter. That is a royal pain and the smears have to be removed or else they build up and produce crapped up and uneven bullet bases. There are several ways to remove these smears. The one I use is to rub the smear (better when hot) with the sharp corner of an ingot; the ingot corner seems to absorb the smear. But the best approach is to prevent the overheating to start with. You can do this by A) lowering the temp. B) Casting slower. C)Cooling the mold as mentioned by pressing a folded damp cloth to the sprue puddle/top of the mold blocks....another version of this is to take a saucer and put some water in it then put a folded cloth/small towel in the water and touch the bottom of the blocks to the cloth. D) Get another mold going and pour alternately...using the molds "in tandem". All of the above works with single, doulble or 4 cavity molds. You might still get frosted bullets. These shoot just as well as non-frosted bullets, but some folks don't like the frosted appearance. The answer to that is to shine the bullets with #0000 steel wool if you deem that important/ necessary. I personally don't care for creating steam clouds around my molds with wet cloths, so I use the two mold system. There are also casters who plunge molds into water to cool them down. They say it works, but I have never tried that and probably won't. Its all your call, but enjoy casting and good shooting. LLS

[454PB]

At times I cool my moulds, but not just the sprue plate. Normally, I'm casting with more than one mould, but if the situation calls for only one mould, I cool it to speed the casting. Heat rises, so the warmest part of the mould is the bottom. I either touch the bottom to a wet sponge, or partially plunge it quickly into a coffee can full of water. I've done this for years with no ill effects.

[GabbyM]

One of those little fans the size of your hand blowing across the work area is simple. In the time it takes to open the mould and drop bullets you'll be cooled off enough. About three seconds per cycle is all you'll need with most molds.

An aluminum plate to set the mould on will draw quite a bit of heat out.

I tried the wet towel routine but didn't like it after a while.

[ohman11]

I used a fan today and it really makes a big difference.

[shotman]

I know many of you have cast for years but if you ever have molten lead blow up you will not have water near it again. I have the scars to prove it rick

[AzShooter]

I've been cooling the sprue with a wet rag for a few months now. The best thing I've seen is that all my bases are perfectly flat. No gauls from the sprue cutter if I opened the mould too fast.

I've also seem much more consistency in my bullet weights.

[Bret4207]

Search here for "BruceB casting method" that will explain it all. It WORKS. Uncle Bruce is a speed casting genius and this makes all the difference, even if you cast slow like I do.

[jack19512]

The best thing I've seen is that all my bases are perfectly flat. No gauls from the sprue cutter if I opened the mould too fast.







I would agree with this also. On the Lee molds when I get a new one the first thing I do before using it is I take the sprue off and lap it and the mold using a piece of glass and fine wet sandpaper. You would be surprised how much smoother the sprue plate moves after doing this.