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View Full Version : How to keep the sprue plate screw tight



selmerfan
04-25-2008, 08:51 AM
I'm using a saeco 2 cav mold and the screw holding the sprue plate on keeps coming loose. If I don't tighten it periodically, every 10 pours or so, I end up with lead between the sprue plate and the block, and this make releasing the sprue from the sprue plate a pain in the rear. It's not a big deal to tighten it, but it would be nice if I didn't have to do it constantly. Any tips?
Selmerfan

BABore
04-25-2008, 08:57 AM
Drill and tap the side of the block for a set screw to lock the hold down screw in place.

HeavyMetal
04-25-2008, 09:31 AM
I've had four seaco's and they all had a set screw to deal with this problem.

If your's hasn't got one +1 on adding it fast! If it does and the plate still works loose cool the mold then adjust for your desired tension and mark the screw top with a small mark of some type making sure it's in alignment with the set screw. Then loosen and remove both screws.

You'll want to make sure the end (point) of the set screw is flat and you'll want to add (file) a flat area to the spot on the sprue plate screw that lines up with the mark you made on the screw head. This area should be close to the marks left by the locking set screw, if it had one. you may have to mark this area as well before you file the flat on it.

Now when you put it back together the flat on the sprue plate screw should provide a "base" for the set screw to lock in on and the issue should go away!

mtgrs737
04-25-2008, 11:56 AM
They make brass tipped set screws if you can find them. If you have enough room you can nip off a short piece of brass brazing rod and put that in the tapped set screw hole and then put the steel set screw in and tighten it against the sprue plate screw. Another way it so use a brass machine screw as a set screw, however it will strip out easily if you are not careful when tightning. Steel threads on steel threads may lead to damaged sprue plate screw threads in your mould blocks. Good luck!

Buckshot
04-26-2008, 12:32 AM
...............The Saeco's aren't issued with a brass interface so it's steel on steel. Bad deal. Boogered threads on the sprueplate (SP) screw are the result and when, or if you have to remove it (meaning you'll ALSO have to put it back later) it will do nothing to improve the threads in the cast iron blocks.

If there is a hobby shop in town, call'em up and ask if they carry brass. Most better ones do. Be sure to ask if they have brass rods. These are used for linkages, control rods, & et'c. Take your mould blocks and get one to fit your Saeco's, Lymans, and whatever else you might have. RCBS moulds come with a brass button but it's easily lost.

Once you have the brass button in there and the SP screw is how you like it, snug the keeper setscrew up, then rotate the SP screw back and forth, then snug the keeper again. Do it one more time and the brass button should be well engraved in the SP screw threads. If there is no hobby shop carrying brass then you can use brass wood, or machine screws of an OD you can snip a piece off of, to go into the keeper hole.

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

floodgate
04-26-2008, 11:18 AM
...or a little snip off the end of a 1/8" brazing rod.

Fg

beagle
04-26-2008, 11:24 AM
I use a "ball" off the end of a beaded key chain. They're brass and are just the right size./beagle

wiljen
04-26-2008, 11:48 AM
A kit for doing the drilling and tapping is on the Group buys as we speak

nvbirdman
04-26-2008, 07:03 PM
I had a Lee mould that the screw kept loosening up. I bought a longer screw and that worked for a while, but when it loosened up again I tossed the mould. Lee moulds are inexpensive.

Morgan Astorbilt
04-26-2008, 07:13 PM
This afternoon, I took off the sprue plate on a new SAECO mold, to mill a channel between fill holes. I looked into the set screw hole, and there was a metal slug for the screw to bear on. Couldn't tell if it was brass or some other metal, it was too deep and wouldn't drop out when I tapped on the block. I'm sure it was softer than the screw, otherwise, why bother to put it in?
Motgan

monadnock#5
04-26-2008, 09:57 PM
Look that mould over carefully selmerfan, and I'll bet you find a set screw hole for the sprue plate screw.

You would expect that they would put the set screw on the side closest to the pivot screw. Not Saeco however. Look at both ends of the mould, instead of the side, and I bet you find what you're looking for.