Sprew plate keeps coming loose..

[JackOfAllTrades]

I've got a Lyman 452460 that functions fine, except that now the sprew plate/screw keeps coming loose about every 3 or four pours. I suppose that the lock/spring washers are toast.

So, what in particular do I look for to replace them at my local hardware store? I'm guessing that there's better and worse choices available.

-Steve

[billyb]

look on the side of the mold and see if there is a set screw to lock the sprue plate screw in place Bill

[1874Sharps]

I have had this problem on a couple of molds and the thing that fixed it for me was Loctite, medium strength. It has enough temperature resistence for this application and is not so strong to prevent the screw from breaking loose if you really want to take it off.

[Le Loup Solitaire]

Good advice so far, especially with regard to checking the set screw on the side of the blocks and making sure that it is tight. There should also be a a thin lock washer or a "wave washer" on the top of the sprue plate to keep it flat...that should be doing its job, with some minimal/light pressure but but not (too) tight. The sprue plate should lie flat on the blocks--not up and down sloppy, but should swing free on its own weight when the blocks are tilted. It has to move like that to allow air to escape (to some extent) and not force/cause wear or galling when it moves on top of the blocks. Use of powdered graphite or Bullshop Lube that is available on this forum between the sprue plate and the tops of the blocks helps a lot/makes things easier. Small thin lockwashers and/or wave washers if in fact you need them are very easy to find in hardware stores and cheap. Neither should wear out easily under minimal pressure. Hope that this helps. LLS

[theperfessor]

For a long time Lyman used what is essentially a split type lock washer to hold down sprue plate. The sharp corners of the split dig into the sprue plate and try to unlock the hinge bolt while ruining the sprue plate. I chuck those thing in the trash and replace them with solid stainless steel flat washers. Others use wave washers. Both work OK. Either is better than the Lyman part and will not damage sprue plate.

You will have a hard time keeping hinge screw at proper tension otherwise.

[beagle]

Wave washer/bellville washer....you need one to act as a bearing on top of the mould blocks. $.25 from Lyman's customer service.

Remove the set screw on the side, drop in a brass bead or a small piece of copper and tighten it down and your troubles should go away./beagle

[JackOfAllTrades]

I'll swing into my local hardware store and pick up a wave washer. The sprue plate screw does have a standard thick lock washer on it that's digging into the plate. That and locktite should do me.

Thanx all.

-Steve

[geargnasher]

Wave washer/bellville washer....you need one to act as a bearing on top of the mould blocks. $.25 from Lyman's customer service.

Remove the set screw on the side, drop in a brass bead or a small piece of copper and tighten it down and your troubles should go away./beagle

My fix for Lyman moulds as well after replacing the washer on top with a polished flat washer.

The Lees get cross-drilled and tapped #8-32 for an allen setbolt, piece of 12 ga. copper wire 1/16" long dropped in the hole before the screw goes in.

Gear