Out of round with one small spot

[Mattog22]

I'm using a Lee 230 gr TL RN .45 6-cav mold. I cast some boolits last night and I measured them, they varied around .4535 to .452 for most areas I measured but it seemed like on a lot of the boolits there was one spot when measured just to the side of the slight seam from the mold that would measure .451. I have my lead at 630-650 degrees and my mold is hot enough that I have to wait for the sprueplate to harden each time. The mold is clean. What could cause the small spot? I called Lee and they said just send it in.

[Echo]

Sounds like it could be a venting problem. As the alloy cools, it shrinks, and if there is insufficient venting in that area, and the alloy isn't hot enough, the shrinkage pulls the alloy away from the wall of the mold, rather than pulling alloy down from the sprue area, since the sprue has solidified before the interior.

I theeenk...

Or something...

[462]

I would determine which cavity is at fault and give it an inspection with as much magnification that's available, looking for any irregularity, and give the mould another thorough cleaning with Dawn dishsoap and hot water.

You didn't say how long you have to wait for the sprue to harden, but the temperature seems a bit on the low side, expecially for an aluminum mould.

If inspection, cleaning and higher temperature doesn't remedy it, you might try lapping the offending cavity.

[NSP64]

Ya gots to run them Lee molds hot.

What alloy are you using?

[Mattog22]

Ww alloy, it's hot enough that I have to wait several seconds for the sprueplate to harden.

[leftiye]

Look for **** - maybe release agent buildup in that area in the cavities which corresponds to the undersized parts of the boolits. Could be hot spots. Any frosting in the shrinking parts?

[Mattog22]

I don't use release agent and they fall easily. I smoked it the first time and never had to since. My boolits are frosted anyway since I'm trying to keep the mold hot. If they aren't frosted it seems like they get shiny and have wrinkles. I'm new to this so maybe Im doing something wrong?

[44man]

I run WW's at about 750* and hold my ladle tight to the plate until the boolit takes all the lead it needs from the ladle, NOT FROM THE SPRUE.
You are too cold and you have to wait for the lead to harden, boolits don't fall out instantly. Speed casting gets you nowhere.

[Mattog22]

I too pour directly into the cavity until it overflows on to the sprueplate. I don't follow, you say Im too cold but have to wait too long for sprue to harden? Please explain. Are you saying my lead temp is causing the out of round boolits? I thought the temp was fine as long as my mold was hot, which I thought it was since it takes so long for the sprue to harden. Thanks for the help

[Mattog22]

Think I figured it out, molds are slightly misaligned, what to do now? Send it back? I have always been sure to lube everything and never bang the molds together.

[MtGun44]

Look for any crude on the mold alignment pins or loose pins or sockets. If you
can't see anything and are sure the mold is misaligned, it needs to go back to
Lee.

They 1 and 2 cav molds can have this from dirt/junk build up on the angled faces
which do the lateral alignment, but the 6 cavs only use the pins, so if it is wrong and
you see nothing obvious, I don't think it can be easily fixed.

Bill

[Mattog22]

I see what you are saying, if it was due to something on the face of the mold it would hold it open slightly. I would not get any undersized areas, it would expand everything. In order to get the smaller areas with larger ones it must be the horizontal alignment. I will check the pins and clean it all up really well and try one more time. If it doesn't work right then I will ship it back.