You guys with Star sizers, riddle me this......

[xr650]

lathesmith,
You referenced A-1/O-1 Tool Steel. Are these dies hard? Has someone hardness tested the dies?

I would think 4140/42 HT 125K Yield 32 HRC would be strong and hard enough.
Am I on the wrong track?

[HTRN]

................The flange is .875" and the body is .750"/.7495". I'm just not real enthused by Star dies, basicly .

So lemme get this straight, you're using 7/8th stock for something with a .875" flange?!

Tha's bad machining practice - a minimum of 20 thousandths cleanup per side is standard. In this case, I'd start at 1" personally.

One of these days I'm going to begin the design and testing of a straight through lube/size press. Hopefully I don't die of old age before it happens!

Are you looking at a full blown sizer or something that goes on a reloading press?

I was kinda joking at first, but on a bit of reflection, and as a Star owner that needs some dies, I wonder if we got a group buy up on Star "blanks" from a CNC shop could we get a really low price and then have them sized internally as needed? We might get a < $5 each or so price if we ordered enough for a CNC lathe run of substantial size, especially with lathesmith's simplified design. Interior sizing and polishing to fit might make them a good bit cheaper than Magma's $40 price.

Bill

$5/blank? Perhaps, if we can order 2000 of them. I've had the exact same part go out the door at $5 and at $200. The only thing that changed was quantity. Keep in mind, that setup time is factored into the price as well as such things as Is this a repeat customer? and Is this a commercial customer? Jobshops in general like repeat customers, who order the same thing a coupla times a year(thus amortizing custom tooling/fixturing), and commercial customers(because they're generally less of a headache). More than likely, if you just walk in off the street, you're gonna get a "go away" price. I think you'd find that at the quantities ordered, Buckshot and others who make/modify dies would actually find it cheaper to make diebodys themselves.

I know this, because I started looking into custom dies as a side business after Stillwell shut down operations. I came to the conclusion that the most economical way to make them was with a small CNC gangtool lathe, and finishing with flexhones. I'm still trying to find out what alloy Magma uses for their dies - I'm probably gonna use prehardened 4340(Rc 38 or so) and then machine them using carbide inserts.

I do like the idea of the straight wall die conversion - if nothing else, it makes the Star able to handle larger bullets. It would be easy to do, if one had a CNC milling machine - just go in with a radiused T slot cutter.. Heck, you could do a special jig where the base sits on a low pin, and destaco's clamp it in place. Call up the program, and watch it go. Would take 5 minutes, tops. You could even do it with a manual mill, but that would involve a facing head with stops like a Waulhaupter(translation: $$$$ - they regularly go for $500-750 on Ebay)
The question is, does the Star base have enough meat in it to have a groove cut in the die hole?


HTRN

[HeavyMetal]

Your quite right about several things, especially the"go away" price at most job shops.

My idea would require a bit more "rerlationship" than is average for a walk in customer!

At the time I posted that thread I was (and did) selling a product to just such a job shop! This relationship will last at least 5 years and during this time I , or someone I work with, will be in contact at least once a month with the end user.

Such relationships can lead to a bit better understanding when they know your not completely full of it.

Again the idea was: If we could order so many, if we could keep the work to a bear minimum, If we could show up with a "blueprint" to show we weren't idiots, could we make this work for both sides? I want a fair price, not favors, I think thats do-able.

You are again correct: we would have to buy or supply 1 inch diameter stock and the machines would be set up to "cut out" flanged blanks or straight blanks with a groove cut in it for the snap ring.

The tolerance's we ask for might be an issue. The center hole no problem we just need a hole.

Groove location might be able to "float" .010 or .015 up or down without creating an issue but I think to make the snap ring idea work the groove for that will simply have to be a specific width, say .125 plus or minus .0005! This way we won't have to worry about the die "flexing" and "digging" into the sizer base and creating a whole new set of problems!

I also think, as I mentioned earlier, that we should really hear from Buckshot about how much and how often he's actually willing to do these dies before we fly off the handle any more than we already have!

[mtgrs737]

Why not just make the ring to the size you want the flange to be and use liquid nitrogen to interferance fit it to the die body.

[monadnock#5]

The price of a cloned Star sizer die would have to get down to Lyman H+I die levels ($20.00 a pop) for me to get excited enough to get in line for a Star lube/sizer. At that price, the whole world of cast shooters will beat a path to "Buckshot$ Machine And Tool Emporium".

At this point, I'm curious as to whether Magma/Star maintains patent rights on their sizer dies?

[lathesmith]

xr650, both Lyman and Star sizer dies are "harder than the hinges of Hell's gates"(thanks Bill). I use O-1 and W-1 for my own personal dies and have never had a problem. However, this is a reason I am really not interested in trying to make these dies on a commercial basis--what is good enough for me may or may not work for the next guy, who wants/needs an exact factory duplicate in every way. As others have mentioned, there may also be some patent infringement issues on this type of business as well.
Remember, the "free" market is only so "free"--while workers of our society don't have any right to organize, the government stands ready to aggressively protect the "rights" of businesses or corporations against those who might draw away some of their profits with a cheaper/superior product. (Sorry about that, I couldn't resist.)
Anyway, on a personal level, and for making some of these dies as a favor to some of the casters here, I believe there is some workable and useable suggestions. I want to order some 3/4 O-1 drill rod and see how good dimensional tolerances are on this stuff; if it is as good as the 13/16 I have purchased, some of the ideas here will be real time-savers and should work great. In the mean time, I'll keep reading....
lathesmith

[HeavyMetal]

I was wondering when someone was going to ask about "Patent Rights" for the Star/Magma.

Patents are good for about 20 years, add a few more for "improvements" and after 30 years a design is "open" for all to use. Royality arrangements during the Patent protected period can also be arranged, some times.

I believe the Star design is at least 80 years old so Patent infringement is not an issue.

However Trademarking is another issue all togther!

So if one wanted to build parts or even produce an improved design of the Star sizer it could be done provided no reference was made to the original.

After examing my two star's I can't help but wonder why it hasn't been cloned?

I can understand why RCBS and Lyman haven't done it they both have to much invested in the current design to market a second design.

But one wonders why someone like dillon hasn't picked up on this?

With a few simple manufacturing changes, to make it easier to build, the Star design can be cost effective to produce!

Buckshot mentioned in one of his posts that someday he'd take a shot a designing a straight threw bullet sizer. As we have the Star any such attempt would be redesigning the wheel!

We have the better mouse trap already! We just need a "smart" manufacturer to produce it!

My opinion is the Star can be made and made profitably and still be competatively priced!

Price is the only reason the Star design has not dominanted the private cast boolit market place! It has always owned to Commercial side of cast Boolits.

[JIMinPHX]

I went as far as having a guy draw up a CAD drawing of the die. I have never been able to open the CAD file though, so I don't know how well he did.
John

If you would like to e-mail that CAD drawing to me, I'll be happy to convert it into a BMP or JPG that anyone can open & send it back to you.

[JIMinPHX]

So lemme get this straight, you're using 7/8th stock for something with a .875" flange?!

Tha's bad machining practice - a minimum of 20 thousandths cleanup per side is standard. In this case, I'd start at 1" personally.

HTRN

If you were starting with a piece of 1018 or some other type of mill-finish stock, I might agree with that statement. Here we are talking about starting with a dimensionally correct piece of tool steel in an application where the OD is not being used as a pilot diameter. I see no problem leaving the stock OD as the flange OD on the finished part for this job.

[JIMinPHX]

Now I don’t have a Star to look at, so I’m just talking off the top of my head here…

But, has anybody thought about maybe making some sort of adapter so that standard Lyman $20 dies could be used in a Star?

[Buckshot]

So lemme get this straight, you're using 7/8th stock for something with a .875" flange?!

Tha's bad machining practice - a minimum of 20 thousandths cleanup per side is standard. In this case, I'd start at 1" personally.

HTRN

............Boy, am I late seeing this I don't see a single problem leaving the .875" OD as it is. The outside circumfrence of the flange doesn't fit inside anything. It's sole purpose is to serve as a stop for the die. The backside of it needs to be (or should be) perpendicular, but it's .875" OD is non critical.

The only critical portion of the Star die body excluding the bore, is the .750" body behind the .875" flange. The die doesn't use 'O' rings as a lube seal. The close machined fit of the die's body to the bore in the press serves the purpose. The dies OAL can be +/- several thousandths.

.............. JIMinPHX, "Now I don’t have a Star to look at, so I’m just talking off the top of my head here…

But, has anybody thought about maybe making some sort of adapter so that standard Lyman $20 dies could be used in a Star?"

I would suspect the issue comes in with how thin the adaptor would have to be. The Star die is .750" on it's sealing surfaces. The Lyman die's body is ~ .702" and at the locking nut end it's ~.720" for maybe a length of .200". Forgetting how you'd hold it in the press's bore, the adaptors would only be .024" thick. The internal AND external ID/OD would both be critical surfaces to seal, and I don't believe Lyman nor RCBS are super critical about that .702" dimension, so the adaptors ID may be problematical.

Then you have the lube hole position bugaboo the Star and it's dies have. The lube holes in both Lyman and RCBS lube dies are huge by comparison.

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

[xpshooter]

If we are looking at doing a bulk blank buy, which I think is a good idea. How much do you actually think the cost difference would be between the original type blank out of 7/8 or 1" vs the new style with the snap ring?

I don't think it would be that much of a cost difference and I would prefer the original type..

If these blanks are cut on a cnc it is not that big of a deal to cut the original type.

But that's just my 2 cents.

I would prefer the center hole <.224.

If we don't do a mass buy, I will probably have the toolmaker at work make the couple blanks I need on their cnc and I will install the lube holes and hone the id myself.

[JIMinPHX]

If I can get my hands on a workable drawing, I wouldn’t mind shopping it around to a few CNC shops that I am friendly with. Unfortunately, John’s CAD file is in an IGS format that none of my CAD programs will touch. I need DWG or DXF formats.

If you guys didn’t mind waiting about 6 or 8 months for this, I might get my CNC machine set back up again, but that seems unrealistic.

[jhrosier]

... Unfortunately, John’s CAD file is in an IGS format that none of my CAD programs will touch. I need DWG or DXF formats. ...

Jim,
If you need some igs files translated, drop me a PM. I have several flavors of cad/cam software that can do this without any problem.

Jack

[Buckshot]

.................If you're talking die BLANKS (basic bore drilled) purchaser doing the ID honing to size and lube holes that would be easy

Using W-1 steel, the least noble of the so called high carbon tool steels, a 36" length of 3/4" is $12.65 (not on sale). The same, only of 7/8" OD is $9 more. With a die body length of 1.6", and parting off, facing, and one piece of unusable scrap you'll get about 20 of'em from each stick. That would be about $0.65 each for .750" material.

Using the 7/8" stock would bring the cost per unit to $0.95 each. Still no big deal for a couple sticks worth if considering only material cost.

Using the .750" stock means you use the circlip for retention. Machining ops would be:

TS = tailstock
TP= Toolpost

1) Face
2) Center drill
3) Drill (TS tool change)
4) Turn center lube clearance (TP tool change)
5) Cut circlip groove (TP tool change)
6) Then ream and /or bore to desired 'minus' tolerance for customer finish honing. (TS or TP toolchange, depending if boring or reaming)
7) Ream tapered lead (TS tool change)
8) Break all edges
9) Part off (TP tool change)
10) Reverse and drill counterbore at end of run (TS tool change)

Using the .875" material to the above you would delete cutting the circlip groove and add plunging the parting off tool maybe .200" behind the flange.

Then you would have to add the TP tool change, and makeing 2-3 passes to remove .125" (.0625" DOC) of material and form the Critical.750" body OD.

Then to drill the counterbore you cannot simply stick the die body backwards into the 5C collet as it only has the thickness of the flange to grip. So after your run is made you swap collets to a 3/4". Because of that 7/8" flange each of the die bodies has to be placed reversed into the collet, and then threaded BACK into the collet closer. This for each and every one.

If the circlip works without issue to retain the die in the press body, I would MUCH rather turn in a groove and forgo the forming of the flange and then bringing almost 1.5"of length to a critical dimension. Finally, the counterbore could be done at the end of the run in the SAME collet without being required to remove and replace it for each and every one. BIG time saver!

Cheaper material, less turning, and the main point is, NO critical dimension to be machined into the die body, as it's recieved already "To size". I'm into the KISS principle big time.

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

[lathesmith]

That's one of the great things about Buckshot. Not only does the man have a way with tools, but also with words! I couldn't have said it any better for sure, he covered most all the bases with post #35.
I now have around 10 dies of the Buckshot design either made or pending, to be used by various guys on the site here. We should very soon be getting some "field experience" on the feasibility of the design for more widespread distribution. I myself will be making all my own dies with this design, it's just more efficient for the Star hand sizer machine.
For some of you guys who insist on the flange design, don't despair. I have been thinking about offering a "rough blank" machined from O-1, for those of you who have a lathe to finish it. This will be a rough machined blank; you finish the OD, ID, and drill your own lube holes. This blank would be priced around $12, plus shipping. For another $5 I'll locate and drill up to three rows of lube holes. This would be the outer large diameter lube hole; the customer would be responsible for boring the die and finish drilling the smaller holes. And finally, for another $5 I would finish drilling these small holes AND rough bore to around .012 undersize.

I'll let this idea float around, if there is enough interest we will get the ball er, lathe turning.All for donations to the site, of course, as the Buckshot design dies are now.
Thanks for supporting the site, and being willing to try new ideas!
lathesmith

[Firebird]

Buckshot

Wouldn't it be easier to turn it around, and do the lower end away from the collet? So you would

1) face
2) drill & ream
3) Counterbore
4) turn to .750", leaving lip against the collet
5) Part off
6) Turn die body around and put the .750" into the collet with lip out
7) Face lipped end of die
8) ream taper
9) break edges

You still have to change from 7/8 the 3/4 collet, but you don't have to mess with trying to put the lip on the backside of the 3/4" collet.

[JIMinPHX]

Or you could use a 3/4 to 7/8 split bushing & just keep running it in the 7/8 collet.

[dragonrider]

All of this discussion got me inspired and I made up this die for my Star for the 360-180 Group buy bullet. I have a 13x36 Clausing/Cholchester Lathe so taking it down from 7/8 to 3/4 is not a problem. My steps are as Firebird stated.
I use a collet block for drilling the holes in the Bridgeport.
I used a .059 drill for this one, 4 holes no steps, this bullet has a large lube groove, for smaller lube grooves I would use a smaller drill and space them to groove spacing with as many rows of holes as grooves. I am going to make a few more and they will be bullet specific as this one is. I will also make punches that will bullet specific, that is that once adjusted it can be removed and replaced without further adjusting. Thus I can insert die, screw in the punch and start lubing.
http://castboolits.gunloads.com/albu...0&pictureid=70

Picture is a little fuzzy, my camera dosn't take good cluseups.

[JIMinPHX]

[QUOTE=Buckshot;353540
.............. JIMinPHX, "Now I don’t have a Star to look at, so I’m just talking off the top of my head here…

But, has anybody thought about maybe making some sort of adapter so that standard Lyman $20 dies could be used in a Star?"

I would suspect the issue comes in with how thin the adaptor would have to be. The Star die is .750" on it's sealing surfaces. The Lyman die's body is ~ .702" and at the locking nut end it's ~.720" for maybe a length of .200". Forgetting how you'd hold it in the press's bore, the adaptors would only be .024" thick. The internal AND external ID/OD would both be critical surfaces to seal, and I don't believe Lyman nor RCBS are super critical about that .702" dimension, so the adaptors ID may be problematical.

Then you have the lube hole position bugaboo the Star and it's dies have. The lube holes in both Lyman and RCBS lube dies are huge by comparison.

...............Buckshot[/QUOTE]

.024 in a round section under tensile load & made out of good material might be a lot stronger than you would think. I've found the Lyman die OD to be held to about a .001" tolerance on the 6 or 8 that I've seen. You can have a few thousandths extra clearance there if you are worried about it since they have an O-ring anyway. I don't know how much of a problem the lube hole size would be since I haven't actually messed with a Star yet. This still looks to me like it might be worth chasing.