Lyman 450 O-ring question.

waco

Springfield, Oregon
The O-ring on the bottom of the press. The one between your bench and press. What is the correct thickness an O.D?
Best place to buy replacements? Lyman? A local source or big box store?
 

fiver

Well-Known Member
I bet your local Lowe's has them in the plumbing section.
the ones for the Star is a number-14 [airc they are like 3/4X15/16--3/32 diameter]
 

smokeywolf

Well-Known Member
If I wanted 100 or 1,000 of the same size O-ring I'd call O-rings Inc. in Los Angeles. If I know the size and want only a half dozen, I'd call McMaster Carr.
 

Bret4207

At the casting bench in the sky. RIP Bret.
Chances are mot o ring assortments like you get at Harbor Freight have something that will work. But either measuring or ordering from Lyman will get you the proper one.
 

Ian

Notorious member
Nope. This is an odd one. It's a National #023 (1-1/16" ID X 1-3/16" OD X 1/16" cross section diameter) I don't even have that size. Normal assortments don't carry the 1/16" size that far. Biggest I go is #22 and skip to #025. O'Reilly auto can get National O-rings, just ask for part number 023.
 
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oscarflytyer

Well-Known Member
Just had a BFO (Blinding Flash of the {maybe, in this case...} Obvious)! What about a 3D printed bottom cap? As I mentioned, I have a 450 coming. AND, I know a guy who does 3D printing, especially reloading type stuff. Sure if we put requirements together, he could spin something up. Might take me sending him my 450, but that wouldn't be a problem. Let me know what you think.
 

fiver

Well-Known Member
it's gotta hold 60-psi back somehow.

I don't know why they didn't make this a screw in piece to begin with.
 

Brad

Benevolent Overlord and site owner
Staff member
They should but it costs $$$$
Most shooters will never have an issue. Maybe we just shoot and cast too much?
 

Arlon

Member
Where is this O-ring. My 450 oozes lube like crazy. Is it loose or on the bottom of the screw shaft?
 

fiver

Well-Known Member
it's on the bottom.
if you flip it over you'll see the staked in part at the bottom.
there is an 0-ring in there.
most usually make a gasket, here is some pics so you can see what the others are dealing with also.
 

Ian

Notorious member
Mine isn't staked, and my 45s don't have that plug machined out, just a hole in the casting machined for the head of the rod.

If you put 5 lb/ft of torque on the screw it creates half a ton of pressure per square inch, not 60 lbs. I checked mine one time with a 50 in/lb torque wrench and couldn't get it to turn against cool 50/50 lube when maxed out, so it takes something more like 2000 psi to get the lube to flow if it isn't at least 60-70 degrees. So yeah, no wonder they leak. Actually, my 45s don't leak, just my 450 with the plug, some lubes I've used softened the o-ring.

Yeah, Walter, that would 'splain the blowout.
 
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358156 hp

At large, whereabouts unknown.
One thing to look at when you finish taking it apart is to see if the tear in the o-ring was caused by over-zealous pecker punching, um I mean factory staking. If the o-ring channel is really rough you might want to consider a little cleanup with a small, fine file. On my two 450s I also placed a flat washer between the mounting surface and the stem carrier (cage?) before tightening it back down to remove some of the play in the system. It did seem to help quite a bit. The best fix of course is a little four letter word- S T A R. :)
 

waco

Springfield, Oregon
One thing to look at when you finish taking it apart is to see if the tear in the o-ring was caused by over-zealous pecker punching, um I mean factory staking. If the o-ring channel is really rough you might want to consider a little cleanup with a small, fine file. On my two 450s I also placed a flat washer between the mounting surface and the stem carrier (cage?) before tightening it back down to remove some of the play in the system. It did seem to help quite a bit. The best fix of course is a little four letter word- S T A R. :)
And now I own one of those too.......
 

Bret4207

At the casting bench in the sky. RIP Bret.
Nope. This is an odd one. It's a National #023 (1-1/16" ID X 1-3/16" OD X 1/16" cross section diameter) I don't even have that size. Normal assortments don't carry the 1/16" size that far. Biggest I go is #22 and skip to #025. O'Reilly auto can get National O-rings, just ask for part number 023.

Or find a friend with an O-ring making kit. They aren't expensive. Find the right diameter, cut for size, super glue the ends together and you have an O-ring, usually it's glued to your finger(s) so you won't lose it...
 

oscarflytyer

Well-Known Member
Or find a friend with an O-ring making kit. They aren't expensive. Find the right diameter, cut for size, super glue the ends together and you have an O-ring, usually it's glued to your finger(s) so you won't lose it...

Didn't even know such a thing existed!