Lyman Cut-Off Screw?

[Mike W1]

Anyone know when Lyman changed the shoulder length as well as the OAL of these screws? Without taking a couple more molds aparts to see which have which ones it doesn't make sense to me. I ordered some parts a couple years back and am pretty sure the longer ones are what I got and the invoice description said for .187 cut-off plate. Being a 3/16 plate would be about .1875 and you'd be adding a belleville washer to that, you also need to put another spacer washer in there. With the shorter shoulder that spacer wouldn't be needed. The longer shoulder works fine if I put my thicker aluminum sprue plates in but I've only seen the thinner steel ones on the DC molds I've had. Going to call Lyman tomorrow and order a couple more screws but thought someone on here might know the whys and wherefores.

 

[358156 hp]

This has always been a mishmash for me. I buy a lot of old moulds, and I've seen all sorts of combinations throughout the years. Add into the equation the sprueplate thickness changes, and the change from the spring washer that looks like a lock washer, to the belleville type washer, and this would be difficult to nail down with any accuracy. Plus you can mix and match to an extent too. This is exactly why I never throw Ideal/Lyman hardware away. Then there's those pesky handle screws...

 

[Elric]

Anyone know when Lyman changed the shoulder length as well as the OAL of these screws?

What is the length under the screw head? The shoulder length? The threaded part plus the solid shaft?

Why I'm interested is one mould I got acts like the sprue plate screw is TOO long, as it bottoms out before tightening the plate down. Maybe a 1/16th of an inch. Never thought the screws might be different... There is a similar issue, the older dual cavity sprue plates have a closer set of holes, .480", and the newer rebuild kits have a skosh wider space between the two pour holes. I had to get the special width...

"From Lyman tech support:
We make two different sprue plates for double cavity moulds. Our most common plate has a .550" center to center hole spacing. This is the one that is packed in the mould rebuild kit and sounds like the same one that you have. Our other plate has a .480" hole spacing. It is part #2998331. This would be available through our customer service department at 1-800-22-lyman."

 

[KeithB]

I was rehabbing a Lyman two holer and tried to use one pf their rebuild kits. Not only was the center spacing between the two holes different, the location of the pivot screw hole looked wrong as well. I finally clamped the blocks in my milling vise and used a center finder to locate the center of the pivot screw, After zeroing my DRO I used the center find to find the center of each cavity and I recorded the offset. I made a new sprue plate. Once the location of the pivot screw hole was determined I zeroed the DRO to that position and then moved to the recorded offsets and drilled/chamfered the holes there. Put them right in the center of the existing cavities.

 

[Mike W1]

What is the length under the screw head? The shoulder length? The threaded part plus the solid shaft?

Why I'm interested is one mould I got acts like the sprue plate screw is TOO long, as it bottoms out before tightening the plate down. Maybe a 1/16th of an inch. Never thought the screws might be different... There is a similar issue, the older dual cavity sprue plates have a closer set of holes, IIRC .440", and the newer rebuild kits have a skosh wider space between the two pour holes. I had to get the special width...

It's likely the shoulder dimension that's giving you the problem. They're on the photo. I've had to use an additional washer as a spacer in order to be able to adjust the sprue plate properly.

 

[fiver]

I'm not sure when they changed.
I have some that have that stupid lock washer, it has been the biggest pain ever, it seems like everyone of them eventually digs in and starts spinning the screw with the plate.

a couple of my molds wear a ground off flat washer with a star washer on top of that and they spin the screw back and forth loosening and tightening each time I open and close the mold.
the others now get some light file work a little bit of dremel touch up and switched over to the wave washer asap after I get them.

 

[Elric]

I have some that have that stupid lock washer, it has been the biggest pain ever, it seems like everyone of them eventually digs in and starts spinning the screw with the plate.

The way I handle the lock washer is hold it in vice-grips and use a belt sander to level off both ends. That way it doesn't dig into the sprue plate or into the plate screw...

http://ps-2.kev009.com/ohlandl/Cast_Bullet/Mold_Adjustment.html

Look under "Lyman Split Washer Defanging"