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charger 1
05-26-2006, 06:59 AM
Plate has started galling top of blocks. Fortunately not near holes,but I know it'll grow. Will a little lyman super moly help,or is there a less messy,better way to stop it? I know that the first thing is to gently draw file with a lathe file to get high spots off,but then what????

Bret4207
05-26-2006, 07:43 AM
If it's an iron mould try fixing the top of the mould and bottom of the sprue plate by rubbing it on a sheet of 320 auto body "sandpaper" laid on a flat surface like a piece of glass. Just rub slowly till the high spot it gone. Don't try to sand past the hump. Same with the spure plate. If aluminum same thing only be even more careful. As for lube- use bullet lube or Bullshops lube or graphite or mould relase or something. All the mould makers say to lube the top and sprue plate that I've seen. I forget from time to time and have to go through this.

Bucks Owin
05-26-2006, 07:51 AM
That "galling" comes from cutting the sprue before it's completely hardened I'll bet and some lead gets smeared around when you knock open the sprue plate. I would NOT take a file to it. Although kinda ugly it'll still make good bullets. When you get the mould hot next time, try scrubbing the "galling" off with a carpenter's pencil. This'll give it some "lube" too. The pencil is all I use on my mould's plate and pins, whether a steel or aluminum mould.....

Try waiting longer for the sprue to set up or have a damp sponge handy to quickly wipe the plate with if slowing down cramps your style..... ;-)

IMHO,

Dennis

BTW, "possibly" you might need to mess with the screw holding the sprue plate on, loosening it off slightly....

44man
05-26-2006, 08:37 AM
It is amazing the damage a little lead under the plate can do. It is very important to keep it cleaned off as soon as any forms. Keep everything lubed good.
One thing else to look for on every mould is a rough edge on the sprue plate. I take all of mine and use a fine file on all the edges, then with some 400 wet or dry on a stick, I polish every edge. You don't want a square edge on the bottom, just nice round highly polished edges.
I have had new moulds that were so bad I would not open the plate once without pulling it and polishing it. I think Lee punches the darn things out and just leaves them as punched. I have seen bad plates on Lyman moulds too. If I see a scratch start, I stop and pull the plate again to fix it.
I cut with a bunch of light taps with a wooden tool I made and I tap downward a little to keep the plate tight against the mould top. The top of my moulds actually get more polished with time.
So first, make the bottom of the plate free of any spot that can scratch.