New Lyman 4 Cavity Mold - First Impressions

[Taterhead]

Tater
You sent a mould back that cast good bullets to your desired spec for a sprue plate? I hope they send that mould back to you with just a new plate because if I have that cast to good spec, I want to keep it.

Yeah, that thought did cross my mind. In the end, I don't know how they could verify the sprue plate closing and hold down issue. Fingers crossed. I also wanted them to look at the cavity that will not release

[Taterhead]

I received a notification that Lyman was sending a new mold as a warranty replacement. Thus far, my experience with CS has been as I would expect: attentive, responsive, and with good communication. Zero complaints. In fact, the communication has been great.

Still to he determined is whether the mold that I get will be the quality expected.

[truckjohn]

Since everything else was great - I think I would have worked with the spruce plate a bit more rather than sending it back.

Also - I have no qualms about drilling and tapping a set screw into the mold block to keep the sprue bolt in place. I have no qualms about polishing out sprue plates so the sprues drop correctly....

On the retaining bolts... Another option would have been to hone the bottom of the sprue plate a bit or perhaps relieve the sprue plate at the bolt to the correct thickness so the shoulder on the retaining bolt stops on the mold blocks. Another option is a small washer under the shoulder of the retaining bolt.

On the situation in American industry.... I have lived through the changes over the last 20 years and they are not good. What I see is a general impatience and a love of the idea that you can just skip to the end without going through the middle - all the while digging up the tree by the roots to see if it is growing. I also see an alarming lack of respect for those with the actual experience with actually doing the hard work to make things succeed in real life. They seem to hope that it just magically takes care of itself - but they don't want to pay the cost to implement the changes necessary to actually accomplish it. Guess what - our competition IS doing those things - and they have made significant gains in the last 20 years.

[Taterhead]

Good points all truckjohn. If you recall from my first post, the block had issues too. One cavity would not release without substantial hammering on the handles.

Also, they specified returning the whole mold, and I didn't want to pick a fight with them about what exactly I intended to return. They were very decent and showed concern, so I am giving them the benefit of the doubt.

I should have the mold in hand in a day or two.

[Taterhead]

Well, the mold arrived today. Disappointed.

They sent an entirely new mold. Completly new packaging. Made 3 months later in May and again inspected by Carla.


Same exact problem. No clearance umder the hold down screw. Also it seems obvious that they it will have the same problem releasing sprues. Roughly finished recesses, and the same issue, if not worse, with the taper not going to the bottom.

I'll fix the sprue plate by honing a little metal to allow clearance under the hold down screw. Also will polish the sprue holes (or whatever they are called).

Not going to bother sending it back, and this will he the first and last mold I buy from them.

Crossing fingers that the cavities will cast the similar dimensions and release better than last time.

[Taterhead]

Double tap.

[dogdoc]

If you read the old 1980 Lyman cast bullet manual they tell you how to tune a mould. So this is nothing new . The problems you had would have been easily fixed if you are mechanical in nature.

[OS OK]

Well...fully aware of this sprue problem, I went ahead and ordered a 4 cav. 452374...



it too had the sprue plate problem...

I used a tapered diamond die grinder bit to relieve that straight portion of the bottom of the hole...I didn't go at it too hard, thought I'd just remove some of that straight part that keeps the sprue hanging in the plate...



It worked...they come out now when the plate swings free of the mould...



Shoddy craftsmanship like this sprue plate ordeal makes it hard to remain loyal.

The problem of having them come out a tad bit too small... .4517" ~ .4519" is not a problem, I expected that part casting with a soft blend like 11 BHN and less because the PC more than makes up for the sizing...I size @ 4525" after the PC.

[Taterhead]

If you read the old 1980 Lyman cast bullet manual they tell you how to tune a mould. So this is nothing new . The problems you had would have been easily fixed if you are mechanical in nature.

I guess that I could try to track down a copy being that I turned the ripe old age of 8 in 1980. Yes, agree that they are approachable corrections. It seemed fair to me to give Lyman a chance to solve their issues. After all, no other new molds I've used required any modifications whatsoever, except a $26 Lee.

[Taterhead]

Hey OS OK, nice looking results! Glad you have a mold running good. Curious, did your sprue plate have clearance issues getting underneath the hold down screw?

[tward]

Tater, I’ve had good luck sharpening the sprue holes with a hardened steel RCBS case deburring tool. Most sprue plates are relatively soft. For flatting the sprue plate I wet a sheet of silicone carbide sandpaper and stick it to a flat marble floor tile or flat glass, work it back and forth then move to a finer grit. I would recommend final finish with 400 to 800 grit. I even had to do a bit of this on a NOE sprue plate with some minor burrs. Good luck with the mold, Tim

[Mitch]

Be Happy the sprue plate is all that is wrong.i have one lyman mold I bought new.4 hole 452 630.Every cavity was different way under sized evein using Lyman #2 alloy.The sprue plate was realy rough.I fixed the sprue plate with 6 flute 45 deg chamfer tool.After trying to call lyman and getting no where.then waiting a month for them to email me back.I sent the thing back and they recut it.5months later I had a mold that cast the size I wanted and runs like a dream.That was 2 years ago.FYI I was 18 in 1980 just started in the tool and die trade.I don't mid fixing small problems with a new mold.but the lyman mold was the worst workmanship have seen so far

[country gent]

I turn up a wood dowel to match the sprues angle then use lapping compound to polish it up. It works great for me. I've bought several lyman moulds and gotten good ones. I have had to lapp some moulds for size with older rifles and bores that were large. I have polished and vented most of my sprue plates because I prefer the vented plate and the polish removes any burrs it may have raised.

[dogdoc]

Bottom line is you should not have to do anything to a new mould but if you want an iron mould with a Lyman design you are stuck. I think accurate will make an iron mould but at a cost. I have seen problems posted on some mihek moulds but rare. All mine are great. I remember having some problems with Lyman moulds back in the early 1980s when I started casting. Most are fine though with some minor tweaking and they are tough as hell.

[OS OK]

Hey OS OK, nice looking results! Glad you have a mold running good. Curious, did your sprue plate have clearance issues getting underneath the hold down screw?

Yes it did, still does because I haven't decided how to start grinding at it and whether or not I want the plate to fit under the screw head when the screw is bottomed out ... or ... whether I'll just red-locktight that screw where the plate will fit under.
Thus far I've loosened the screw to accommodate the plate and haven't had any problems with creating a gap under the plate over the top of the mould.

If I had my rathers, I'd rather have the screw bottomed out and tight and have the sprue plate swing under that screw shoulder 'snuggly' without it trying to force the blocks apart...it's a delicate balance.

I'm mulling on the problem currently....but that mould is casting like a house a fire!

[Conditor22]

OSOK you might try putting a very small piece of lead shot in the hole adding shot until the screw stops where you want it to. If you get too much a small drill bit can fix that.

IF Lyman wants to keep charging what they are for their products, they need to get their act together. Lyman and RCBS used to be 2 of the best, RCBS still is but Lyman ......... Outsourcing, cutting corners, lack of quality control???

[OS OK]

OSOK you might try putting a very small piece of lead shot in the hole adding shot until the screw stops where you want it to. If you get too much a small drill bit can fix that.

IF Lyman wants to keep charging what they are for their products, they need to get their act together. Lyman and RCBS used to be 2 of the best, RCBS still is but Lyman ......... Outsourcing, cutting corners, lack of quality control???

Well, as I said Jim I'm mulling on it at the moment...leaning heavy to the idea of drilling the block and installing a 6/32 set screw. Laziness is the only thing besides a dang cold shop that prevents me doing it yet.

I've been loyal to Lyman and RCBS for 41 years now but it's getting tougher every time I run into something like this. I sent my contact at Lyman a picture and explanation...time will tell if she gets back to me or if she even has an idea of what I'm talking about.

[Mitch]

OS OK I add the set screw to any mold that is in need of one.Likely the best way for fix it you have the know how to do it.i have found a trip the the hardwear to get some brass set screws is best.I agree there should be no work to do with a new mold you payed good money for.I have molds from RCBS.LBT,MP,NOE.lymanand lee.the only ones to need a lot of work so far have been the lee and lyman.There should not be the game os send it back or replaceing things that are expencive.

[dogdoc]

I wish rcbs made 4 cavity iron moulds. 2 cavities just too slow for me and I have a bunch of them

[Conditor22]

I dunno, 4 cavity iron molds seem to be getting really heavy faster now.

I can just imagine what those old 18 and 24 cavity iron molds weighed