View Full Version : It's great to see a casting forum; one question about lee molds
August 11, 2009, 03:33 PM
I have one lee mold that 'sticks' when I try to open it, a 6 cavity mold. I noticed the bushing that the rear pin fits into will come out just a bit. I assume that is what is causing the sticking. Has anyone just peened or staked a bit of the Aluminum around the bushing to get it to hold tighter? And if it continues to stick, what do I look at next?
August 11, 2009, 03:52 PM
To help the stick problem, have you tried just a touch of lube? Not too much or it will migrate into the mold cavities...but just enough to help the release of the sprue plate. As far as tightening it, tighten it down with a wrench. If you get it too tight though, the sprue plate may slide under it. There is a fine line. I had the same problem with a lyman 4-cavity mold. The bolt on the far side of the mold that the sprue plate slides under to "lock" it in place came loose and was causing the base of the boolits to be funky (because there was a gap between the sprue plate and the top of the blocks.) I tightened it down until it was firmly screwed in and I knew it wouldn't come loose, but then I couldn't get the sprue plate to slide under it. So, what I did was take a thin piece of copper and used it as a spacer to tighten the bolt down on to. This raised it up and still gave me the ability to tightten it down so it wouldn't back out, and my sprue plate slides under it nicely. It takes some trial and error. Remember the sprue plate should slide under it fairly easily. If your bushing is too tight, then it will be too hard to open the sprue plate and you may find you have venting problem. Lyman claims that some venting occurs between the sprue plate and the top of the blocks. Is it true, I would probably think so! Good luck!
August 13, 2009, 12:14 PM
David, the locator pins should definitely be lubricated with something. They recommend bullet lube but in my experience it will migrate to the cavities to interfere badly with fillout. Causes wrinkles in the boolits. Over on cast boolits . com, there's a guy that lives and works in Alaska. His business is called bullshop. He makes a lube that's called bullplate lube that's a high temp oil for use on locator pins and sprue plates. It doesn't oxidize, or migrate, so you can even use it on the underside of the sprue plate.
I use it for the mold handle pivots, the sprue plate hold down screw, and the locator pins. Take a look at his bio on his website. He lives 7 miles from his mailbox! And 30 miles from town. So give him a couple weeks to get your order to you.
As for the pin bushing walking out of the mold, you certainly could try staking it to hold it in. BUT be very careful to NOT cause the face of the mold to have a "high spot" which would prevent it from closing completely. I think if the pins and bushings are properly lubricated, they will stay put, at least mine do.
August 13, 2009, 05:58 PM
Those bushings have their back side exposed in the mold handle channel. Push the bushing part way out and use a sharp punch to put dimples in the aluminum around the edge of the hole from the mold handle channel side, then press the bushing back in. That should grab it. Be careful pressing it in that it is square. An arbor press and correct size driving punch or dowel pin are recommended. Place the opposing block against it to check. You want it in just far enough that the pin kisses the edge of it and aligns the block on closing. Too far in and you won't have registration. Too far out and the pin may jam into it and stick. Hmm. Sound familiar? You want the block to close just as the wiggle room around the pin disappears.
After that, the lube suggestions may be followed. Simply burnishing in some molybdenum disulphide powder would help. Twirl Q-tip with a little of the stuff on it in the bushing and buff the pin with it.
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