Lee mold problem

Deltadart

New member
I have a new Lee mold in .530 RB. When I tried it out today the screw holding the sprue plate kept working loose as I used the mold. I called the factory and they said let it cool down to room temperature then tighten the screw down. That did not work, same problem screw keeps turning each time the plate is moved out to cut the sprue. Does anyone have a fix for this. Other than drill & tap a hole to put a set screw in to hold the screw in place, like the Lyman molds have.
 
Hi Gary.
They are aluminum. No the hole is good. I slowly snugged the screw up a few times, did not put much pressure on it. According to the folks at Lee that will strip the threads. I can drill and tap but I was hoping not to need to do that, but if not the screw will just back all the way out.
 
I had an old Lee mold that did that. What I did was drill and tap, from the side, for a little brass "set screw" to lock the sprew plate screw.
 
Thanks for the suggestions. I'll try Hawgs idea first, but if not I may end up doing Gary's. Would be great if Lee at least drilled and tapped during manufacture even if they did not install the screw.
 
That screw needs a little lube, just as 243winxb has said.
Give it just a touch of wax used for fluxing or the CLP.
Like I said just a touch, your lubing the screw not the whole sprue plate.
 
Try putting a few strands of steel wool in the hole to give the screw something to bite on.
This seems strange but works like a magic charm .
I pulled a few strands of 0000 steel wool from a pad , evenly spaced them into the hole with a chop stick and carefully screwed the bolt back in place ...make sure all the washers are in the right places and put a drop of synthetic 2-stroke oil under the sprue plate to lubricate where they rub when opening and closing .
My bolt loosened every other cast , put strands of steel wool in hole and after several casting sessions it has not loosened ... I put a screwdriver on the bolt but it didn't want to easily un-screw , I was going to clean the block top , when the bolt held tight I left it alone ... that's been about 4 years ago ...!!!
Try it ... very easy , quick and cheap fix and if it doesn't work ... Oh Well , nothing Lost.
Gary
PS - use the synthetic 2-stroke oil as mould lube , apply with Q-tip sparingly , a tiny bottle will last a lifetime ... good stuff , better than beeswax !
The steel and aluminum like to gall so keep lubricated .
 
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Can you drill the screw hole all the way through & tap it so you can put a set screw in from the bottom to act as a jam screw.
 
7.62 Man I don't know. If so that would work as well. I seems as though the lube on the screw seems to get sticky with heat to act like a staking compound. And the the steel wool strands would cause the screw to bind up as well.
 
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Can you drill the screw hole all the way through & tap it so you can put a set screw in from the bottom to act as a jam screw.

For the aluminum threads in the mold, I would opt for a side drilled set screw personally. I would be concerned with a jam screw like you reference would put pressure on the aluminum threads, which is what you’re trying to protect. A side drilled set screw will put no pressure on the threads that could cause them to strip out.
 
5Whiskey, that is what I am doing. I have 15 of the Lee molds, along with many Lyman and RCBS molds which prefer. But you have to take what you can get sometimes. Most of the Lee molds are pretty old, from a time when money was in short supply, but they do work. I set up the Unimat in the vertical position and it is simple operation. That way they can all be done and no worry about dealing with this again.
 
Hi Hdbiker
I did that twice. Called the Lee facility and spoke with their technical guy. He told me "to let the mold cool down to room temperature then tighten the screw as much as I wanted". The aluminum threads could be easily damaged doing that, so I let it cool down, then just snugged it up, the sprue plate would barely swing under its own weight. Then started using the mold again. Same problem.
 
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