Lee 6-cavity alignment pins "walking"?

[dahermit]

I have had a few Lee six cavity moulds that warped and I could see daylight between the halves of the mold. Researching the problem on here, someone had posted that the Lee six cavity molds are notorious for the alignment pins to "walk" (move from their original position) and hold the mold halves slightly apart.

However, using all my skills as a bullet caster with 55 years of experience and years as a machine tool instructor (in light of that, please do not suggest there could be dirt, lead, lube holding the blocks open), I determined that my alignment pins had not walked, but due to the difficulty in getting them back into the blocks furter, it is extremely unlikely that the the pins had moved in the first place. Logically, if they had moved, they would not be so resistant to being moved back with a hammer and punch.

Therefore, if you have had a bonafide experience with the alignment pins on a Lee six-cavity mold actually moving and holding the blocks open, I would like to hear about it. And, just how you determined that the pins had moved and it was not a case of the blocks warping.

[tazman]

In my case, one of the pins moved slightly and held the mold open on one end. Only the one pin moved and due to how the mold was held open, it was obvious. You could see the pin between the blocks holding the mold open.
I moved the pin back into place and have had no issues since.
I have several Lee 6 cavity molds and that was the only one I have ever had problems like that with.

[Conditor22]

Tazman makes sense, where do you see the most light through the mold? in the middle or at one of the ends where the pins are?

[jcren]

I has one where one pin backed into the block slightly, causing misalignment due to the mold halves being able to move up and down slightly. Just got the mold good and hot and drifted it a bit too much then clamped the mold halves to set it back correctly. Haven't had it happen again.

[dahermit]

I moved the pin back into place and have had no issues since.

How much effort/force did it take to get the pin back in place. If it took little effort, then it is likely the pin indeed had moved. However, in my case (about three different molds), the pins were still tight, leading me to believe that my pins had not moved.

[dahermit]

Tazman makes sense, where do you see the most light through the mold? in the middle or at one of the ends where the pins are?

My original post: "if you have had a bonafide experience with the alignment pins on a Lee six-cavity mold actually moving and holding the blocks open, I would like to hear about it." Do you have such experience?

[jethunter]

I've seen a gap on Lee 6c twice. On one an alignment pin had shifted. The other one was a warped block.

[tazman]

How much effort/force did it take to get the pin back in place. If it took little effort, then it is likely the pin indeed had moved. However, in my case (about three different molds), the pins were still tight, leading me to believe that my pins had not moved.

It took some significant pressure but wasn't overly difficult. After moving the pin, the gap disappeared.
I am not about to say a mold block can't warp even though I have never had one of my Lee molds do that. I had an H&G mold that was warped .002 in the center and could never get it straightened out.
Those old steel molds are tough!

[Conditor22]

My original post: "if you have had a bonafide experience with the alignment pins on a Lee six-cavity mold actually moving and holding the blocks open, I would like to hear about it." Do you have such experience?

That why I asked where the light was showing through the most at.

I have 18 of them, I have been using the Lee 6 cavity molds for years.

I asked where the gap was because long molds have been known to warp. I don't know how you treat your molds.

if the gap is at the pins. first look closely around the pin to make sure there is nothing there (lead splatter or ?) which is keeping the mold from closing.
If the is an obstruction or build up you can remove it with a pick or small scraping tool.

IF the pin is stuck you can first soak the pin in a 50/50 solution of ATF and acetone then set the mold half on a flat sturdy surface and tap the pin back in, a couple thousandth makes a big difference. try not to go to far or the mold will be sloppy. IF you go to far mate the 2 halves together with the pin side up. put a flat block of wood on the mold and snugly clamp the mold to the solid surface. give the pin a couple light taps with a proper sized punch and re-check the closing an see if the sides still move. repeat if needed.

IF the pin doesn't want to move, first set that mold half on a hotplate 400°. when the half is hot, move it to the flat place and touch the pin with a piece of ice or a frozen piece of metal the try tapping the pin again.

On one occasion I put the mold halves in a vise between two pieces of hard plastic and clamped it together overnight. this worked but I would try the punch method first...
but that's just me.

[Springfield]

Walk? I've had moulds that I have used for quite a few bullets and the pin fell clean out of the hole. Granted, I probably cast at least 10-20+ thousand bullets in those, but the pins do indeed move. Eventually the sprue pivot pin will strip out also, just a matter of time. LEE can call them "commercial" moulds all they want, but they just aren't. Also, the pins move when the mould is hot, so if you want to push the pin back it should be hot again. Aluminum does expand more than the steel pins.

[Gaseous Maximus]

I have, I think, seven of the above mentioned molds. For what its worth, and I realize it doesn't pertain to the orig. question, but of these 7, 3 of them had gaps from the factory. I screwed up one set of pins trying to drive them back in. Eventually, drove them all the way through from the back, repointed them in my lathe and drove them back in from the rear. The pins in my molds were real tight, but I can only speak for mine. I agree with Springfield on the pivot pin. Also, for what its worth, cooling molds with a damp whatever, doesn't strike me as a particularly fine idea.









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[dahermit]

...but of these 7, 3 of them had gaps from the factory.

I experianced that also...not closing, new...right out of the box.

[dahermit]

I have never had one of my Lee molds do that.

The phenomenon seems to be limited to those long, six-cavity molds. The shorter (two-cavity) seem, in my experience, to be too short to warp. However, I have not wasted my time with Lee 2-cavity molds for some years now (save for one with which I wanted to experiment the bullets from, then switched to a six-cavity).

[dahermit]

if the gap is at the pins. first look closely around the pin to make sure there is nothing there (lead splatter or ?) which is keeping the mold from closing.
If the is an obstruction or build up you can remove it with a pick or small scraping tool.

What did I say in my original post?

[dahermit]

I question the in some/most instances, that the alignment pins will/can move in normal use inasmuch as, if they moved in normal use, they would have to be loose to begin with or have become loose. If so, they would not be hard move back into position again...would not need very high heat, etc. It just does not make sense to me that a pin would loosen, move a bit ("walk"), and then get tight again. So, that is why I asked about the alignment pins "walking" (moving), in Lee six-cavity molds. In the three or four I have observed light between the halves (not counting the one that would not close completely, new, out of the box), there was nothing done to them that would account for the pins moving, causing the problem and certainly the pins were not loose inasmuch as they are very resistant to being moved back with a hammer and appropriate size pin punch (female side). Therefore at this point, I am convinced that the cause of my problems, is warping of those long mould halves, not loose pins. It may be noteable that I am a high volume caster, using two six-cavity molds at a time, one filled and cooling while the other is being filled. I pre-heat them on a hot plate before starting to cast. The apparent warpage begins after thousands of bullets have been cast.

[dahermit]

Also, for what its worth, cooling molds with a damp whatever, doesn't strike me as a particularly fine idea.

Yes, I don't do that either...I cast with two, six-cavity molds, so the cadance allows for one to cool as I fill the other. Back in the "old days" when I only had one, two-cavity Lee molds, I did fool around with a "damp whatever", to cool the mold, but have not done that for years and only use six-cavity Lee's now.

[GhostHawk]

I happened to look at one of my 6 cav molds prior to placing it on the pot to warm.

Daylight between the 2 sides in a rainbow.

Funny thing was when I pulled it off the pot the daylight was gone. It matched up and aligned perfectly. Dropped lead into it and it made perfect bullets.

Ok, note to self. Don't sweat cold molds. Get em hot then look if there is a problem.

[JonB_in_Glencoe]

My first 6 cavity mold (40 cal TL mold) and I think? it became warped due to me unknowingly over-heating it on a hot plate, I was puring pure soft lead at a higher temperature then one would with COWW alloy, casting thousands, maybe that caused the problem? Anyway, at some point, I noticed it was difficult to open and close when it was hot, after it cooled down it would open and close just fine, but that is when I could see a gap at one end of the mold halves when closed.
That is the only experience I ever had with a warping problem of a Lee 6 cav.
I have many Lee 6 cav molds, three of them have cast thousands of boolits without the warping problem.

[Conditor22]

I also had a new mold not close completely when the handle was installed.
I ended up drilling out the holes in the handle solving the problem. the handle/holes weren't wide enough (like trying to put a Lyman 1 cavity handle on a 2 cavity mold).
If you get something between the handle and the mold that will also happen.

The pins are more likely to move when the mold is hot.
What boolit are you casting?
How hot are you running your pot?
I do most of my casting (with a PID) between 680 and 720 unless I'm casting pure.
I have a 6 CAV 358-158-RF that has cast well over 30,000 boolits (2,000) last week. I cool the mold on a wet rag and it still works like new.
I preheat my molds to 350 and lube my molds before each use and several times during long casting sessions
I've had several sprue plates warp (I read CB has a member in Canada that make steel sprue plate for the Lee 6) but never a mold.
You can always call Lee Precision at 262-673-3075 and ask to talk to Petter