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Jeff Davis
08-14-2009, 10:20 PM
I have a Lyman 4 cav 44cal swc 240 that has a sprue plate with an issue.
I was casting the other day and the plate began to stop its return swing
from cutting. \

By this, I mean the plate seems to catch on the edge of the mold and stop,
almost like it warped.

Was it heat expansion of the plate causing it to swell or a lack of lube under
the plate?

Is it fixable or did I screw up too much?

Thanks in advance for your help!

Jeff

theperfessor
08-14-2009, 11:09 PM
Jeff -

I haven't bought a new Lyman 4 cav in four or five years so if your's is new this might not apply. The "spring" Lyman uses to hold down the sprue plate under the head of the pivot screw is really a bloody lockwasher! It has sharp ends where its been cut and formed into a helix. It will gouge your sprue plate and act to loosen the pivot screw every time you cycle it.

It will often cause the sprue plate to tighten up at some point before its fully closed. I used to use a Dremel tool to round off the sharp corners but eventually got to where I just toss them and put two stainless steel flatwashers under the screw head. Other people use a 1/4" wave washer. Either way works fine.

You may still have a burr or a warped screw plate but I'd certainly check the Lyman spring.

P.S. BullPlate works great on steel molds too.

HeavyMetal
08-15-2009, 11:49 AM
I actually had one tighten up and snap off the screw before I realized it!

Removing the sprue plate and inspecting the bolt, plate and top of the block has become the SOP on any mold I buy, new or used, before Iputit into use.

Currently I have a DE wadcutter mold, Lyman 4 banger, that the sprue plate was to thick on! If you didn't have the stop screw loose you couldn't close the plate. In use the stop screw would drop out after a number of cast's.

In the end I took the plate off and milled a "slot" across the top of it to thin the area where it fit under the stop screw. Look ugly but now fits tight and the screw doesn't come loose anymore!

The lock washers are an issue and, I think, Lyman has moved to the wave type washer but can't swear to it.

Mold prep is just as important as anything else in the casting cycle so adopt the trust but verifiy mind set and check each mold as it comes into your possesion.

Bull plate lube or anti size compounds are both good for the pivot points on any mold.

Buckshot
08-15-2009, 10:41 PM
............I routinely change out the supplied sprueplate pivit bolt hardware with what I personally consider as better. I put on a wave washer and then a brass washer against the SP. Lyman's modified lockwasher is ludicrous, and I don't care for belleville washers in this application either.

...............Buckshot

cajun shooter
08-16-2009, 07:26 AM
You can do as heavy metal post. I too broke a bolt before redoing the plate as Buckshot did his. You would think that someone who was the grandfather to mold making would do it better.

Beekeeper
08-16-2009, 10:06 AM
I am sure it has been posted somewhere but either I don't know how to use search correctly or haven't found the key words yet.
What is the procedure for removing the sprueplate screw from a Lee 2 holer without ruining it?
I have a sprue plate I want to lap and can't figure how to remove it without ruoining the screw.

Jim

Calamity Jake
08-16-2009, 10:42 AM
I am sure it has been posted somewhere but either I don't know how to use search correctly or haven't found the key words yet.
What is the procedure for removing the sprueplate screw from a Lee 2 holer without ruining it?
I have a sprue plate I want to lap and can't figure how to remove it without ruoining the screw.

Jim

I dought you will get it out without ruoining it. It is a self tapping screw and installed with a power driver and is tight. Be prepaired to tap the hole and install a new screw along with drilling and tapping a lock screw into the side of the mold.

There is a sticky here some where discribing the above fix.

Jeff Davis
08-16-2009, 11:19 AM
Thank you for the information thus far. Where can I get wave washers from and what size do I need? Also, what is Bullplate and where do I get some?

Thank you again gentlemen.

Jeff

jhrosier
08-16-2009, 11:26 AM
Jeff,
You should be able to get wave washers from McMaster-Carr.
They have a website with a pretty good search function.

http://www.mcmaster.com/#wave-washers/=37pvsp

Jack

theperfessor
08-16-2009, 11:33 AM
Go to the vendor links section in the swapping and selling section for BulPlate lube. They're good folks to work with. Buy two bottles, its cheap and if you're like me you'll spill one of them eventually. :-D

HeavyMetal
08-16-2009, 11:40 AM
Getting the screws out of a Lee mold can be some work!

I have a small Machinists vise set up on my mill, so I clamp the mold in that and get the biggest screw driver that I can, read longest, that fits the screw very tightly and crankit out!

So far each one I've "tampered" with has come out on the first try! Do not attempt this if you have no way to hold the mold or an incorrect screw driver.

Afterwards I drill and tap a hole for a set screw, flatten the sprue plate as needed and put it back together.

Making sure I lube it well with either bull plate lube or anti size compound when I put it together!

badgeredd
08-16-2009, 01:45 PM
I've found that often (but not always) if you heat the mold up to casting temp, and then does as Heavy metal suggested QUICKLY, the screw will come loose about 75% of the time. I get everything around and ready so there is no delay between heating the mold up and the attempted screw removal.

Edd

462
08-17-2009, 10:56 AM
Beekeeper,

Once the sprue plate screw has been removed, it is imperative that a set screw be installed to keep in it place, if not the screw will back out when casting.

TAWILDCATT
08-17-2009, 12:37 PM
I have 3 lyman 4 cavity molds used them for 30 yrs never had problem.did lyman change at one time.only thing I did was ball mill the cavities for long groove.a la H&G.:coffee:[smilie=1:

Jeff Davis
08-17-2009, 10:28 PM
I bought mine used with handles for $50 and had a very successful casting session with it on the 1st time, no hang ups and good bullets on the 2nd cast

This time, it started acting up after cast number 13 ( an omen or what!) I found that reversing the swing of the sprue plate leveled it out and I got a few more casts out of it before it hung up again. The trick didn't work a 2nd time

dardascastbullets
08-21-2009, 04:58 PM
Hi Jeff,

It is my suggestion for you to remove the sprue plate (which should be done on a periodical basis anyway) and inspect the top of the mould and the bottom of the sprue plate for burrs. I would suggest obtaining a toolmaker's stone (ruby red) to stone the surfaces. Then apply a small amount of Permatex Anti Sieze (with a Q Tip) to the area surrounding the sprue screw hole. This will remedy your binding and provide you many hours of trouble-free service. Remember to inspect those surfaces on a periodical basis!

Good luck!

theperfessor
08-21-2009, 05:12 PM
TAWILDCATT - I don't know if or when Lyman has made any changes to sprue plate screw and tensioning spring/lockwasher but I have 8 or 9 Lyman 4 cavs and everyone of them USED to have the lousy lockwasher spring. I say used to 'cause I have replaced them all with SS flatwashers. It is highly possible that they have used different spring-things over the years.

By the way, I was interested in your reference in another posting to the Evansville Cartridge Co. I have several examples of their WWII era ammo. I grew up (and still live) in Evansville IN. A couple years ago I found some empty ECC .45 ACP cases at range. The firing pin indent was light and off center but apparently they still went off after 60+ years. Almost broke my heart, I would have bought the shooter several boxes of premium ammo for a box of ECCs!