closed sprue plate while casting

[BJung]

How much do you close your sprue plate while casting? I was casting with my 6 cavity 38-148 WC today and noticed that I don't force my sprue plate completely. While it's possible when the mold is being stored, the sprue plate needs to be forced closed and I'm thinking that this must be from metal expansion. My concern is forcing the sprue plate closed and distorting the mold so the two halves don't close. As long as the hole lines up with the cavity, I am fine. Is what I am doing correct? I'm just wondering.

[Winger Ed.]

I've had rather bad luck forcing, and gorilla fisting things made out of Aluminum.

For me: If it works-- then it's OK and doesn't need fixing.

[megasupermagnum]

I don't force it at all. Sprue plates are adjustable. I adjust them when hot so they close easily.

[GregLaROCHE]

There’s a nice sweet spot sprue plates should be tightened to. Never too tight especially with aluminum. Make sure the plate is perfectly flat. Some people use something to lube where it hinges.

[Teddy (punchie)]

Using a block and fine 420 sandpaper and see if worn funny. Most just need cleaned up. Some are bent and need flatted out, two hard wood blocks and hit in the right spot. Then hand sand see if I got and sand flat. I'm not sure how all the heavy scratches get into the sprue plates but I've found enough. Never use a grinder or wire wheel, if that bad maybe a very fine file, then sand 120 220 to 420. .... Go work to do setting on porch or while watching a program

[Outer Rondacker]

Im with Ed on this one.

[Larry Gibson]

With Lee 6 cavity moulds I close the sprue plate all the way then back the handle pressure off within the play before it begins to cam open. Sprue holes still are centered over the cavity that way.

[imashooter2]

What you describe makes no sense to me. My Lee 6s close until the sprue plate hits the stop with no particular force applied. Many different molds. All the same.

[Mk42gunner]

With Lee six cavity molds, if the sprue plate isn't completely closed you lose the benefit of the camming action when cutting the sprue.

Don't ham fist it closed, but also don't hold it closed when filling the mold either.

Robert

[kevin c]

^^^

You want difficult bordering on impossible? Try cutting the sprue on an eight cavity pour when, as Robert describes, there isn’t any leverage. Even a little misalignment from not closing the plate completely against the stop makes the cam lose most if not all its mechanical advantage. You’ll both feel it, and, if you actually manage to cut the sprue, you’ll see it in the off center marks on the bullet bases.

That being said, the MP molds have a spring washer on both the pivot and stop bolts and the bolt holes seem to be drilled and threaded to just the right depth which reduces (but doesn’t eliminate) over tightening. The plates stay closed without needing handle pressure. Closing the plate to a positive stop against the stop bolt and visually confirming that it’s aligned with the blocks seems enough.

[Rich/WIS]

The stop on the Lee 6 cav is spring loaded to press down on the sprue plate. When lubing the mold a drop of 2 cycle oil on the shaft will keep the stop from seizing and not sliding up and down. A little oil on the beveled surface will also aid in closing the sprue plate.

[JonB_in_Glencoe]

What you describe makes no sense to me. My Lee 6s close until the sprue plate hits the stop with no particular force applied. Many different molds. All the same.

I have found the same to be true.
let me add, if sprue plate lube doesn't reduce the friction, then maybe the OP's sprue plate needs some adjustment...BUT, the way the Lee 6 cav sprue plate mounts, if you "adjust it", you'll likely need to install some setscrews. See this thread for a video.
https://castboolits.gunloads.com/sho...ld-maintenance

[megasupermagnum]

I have found the same to be true.
let me add, if sprue plate lube doesn't reduce the friction, then maybe the OP's sprue plate needs some adjustment...BUT, the way the Lee 6 cav sprue plate mounts, if you "adjust it", you'll likely need to install some setscrews. See this thread for a video.
https://castboolits.gunloads.com/sho...ld-maintenance

I forgot about the Lee 6 cavity style. The setscrew is probably the best way. An alternative that I use is to file that corner of the sprue plate down. I've only had to do this to one mold, and it works perfectly.

[Willie T]

Take a close look at the mold faces. If you get a small metal deposit building on the mold face while casting, the blocks will not close the same. It does not take much. The sprue plate getting sticky to close all the way is a tip off that something may be wonky with the way the mold halves are going together.
Willie

Edit to add:
To answer your question- Yes I close the sprue plate all the way every time. One of several things I pay attention to in the pursuit of consistency.