Tiny little pins...how would YOU make them?

[michiganbuck]

Another common thing I did was to collet hold a part and grind a small point on the out end to set into a female tail center for the next operation. Often that might take 30 seconds per part and give about and less than .0005 run out, and insure stabilizing the out end of the part with the point later snubbed off to desired part length.

This could take less length than putting a normal (concave) center, and with many/most parts hard putting in a normal center was not possible

 

[DanielG]

I would probably tap the end of a piece of round bar M1.6, then red loctite the set screw in. Machine the sticking out bit, then throw it in the oven to break the loctite. I'm not saying that it would work, but that would be my first go.

 

[EPAIII]

So buy 1000 and toss 992. Everybody is happy!

I would have

What’s your price for 8 parts? Most Swiss guys give me weird looks when I ask for 8 parts. It’s just not in their mindset even when I am willing to pay.

Now Marcus is pretty valuable, so Swiss shop has a chance on these.

 

[Screwmachine]

Funny you guy talking about levin lathes, I just came across this small pile of them being auctioned off in California. Don't know anything about these, in particular, or them, levin lathes in general, never having seen one in person.

levin Auctions Online | Bidspotter.com

Bid online on 0 levin auction lots for sale at Bidspotter.com

www.bidspotter.com

Hmm, I wonder if that's some stuff out of Levin itself. They're in Sante Fe Springs, just a short distance from there.

 

[just Dave]

I picked up a little cutter grinder a few years back, it is a dream for little jobs like this on heat treated set screws dowel pins and such.

 

[ryancoleman1987]

Wow, staring bid of $5. Thanks for sharing that, I may try to snatch one of those.

 

[L Vanice]

Hmm, I wonder if that's some stuff out of Levin itself. They're in Sante Fe Springs, just a short distance from there.

The auction is for Optel-Matic Inc. who had lots of Swiss automatics but also a bunch of Levin turret lathes, Levin manual lathes with milling attachments and Levin drill presses.

Optel-Matic, Inc. - South El Monte, California (CA) @ ProcessRegister.com

www.processregister.com

In the old days, Reliable Tool would have bought all of it and put it on eBay. And then I would have bid because Reliable had reasonable shipping charges and great packing guys.

The auctioneers have made the collets into lots and called each lot "Levin collets." But most of the lots are collets for the Swiss autos. There are four boxes of up to 90 Levin collets. Many of the collets will have been converted into scrap metal with misuse, but I would still buy them and hope for some good ones if it did not involve a trip to California. Levin lathes that have been used in a production facility are often in sad shape. You want one from a hobby shop or watch repairer. I got a beauty once that came from a mechanical pencil maker's experimental shop, and showed no use on some of the accessories.

Larry

 

[mnl]

This all reminds me of one of our spectacular failures, trying to make 000-120 screws from 0.9999 silver. Starting mater was 1/4” dia round, which even 40 years ago was $100/ inch. We both a nicely kitted Levin and a couple of HLVHs. The Levin could hit the diameter we wanted a couple of tenths better that the HLVH, but no single point threading, so it was necessary to transfer. The problem was that as soon as the threading tool touched the part it crawled over the top of the tool. We turned a few hundred dollars of rod into chips and little twisted bits. Then we decided that using 0.925 (sterling) wouldn’t be the end of the world. We got three good screws in the first four attempts.

 

[L Vanice]

This all reminds me of one of our spectacular failures, trying to make 000-120 screws from 0.9999 silver. Starting mater was 1/4” dia round, which even 40 years ago was $100/ inch. We both a nicely kitted Levin and a couple of HLVHs. The Levin could hit the diameter we wanted a couple of tenths better that the HLVH, but no single point threading, so it was necessary to transfer. The problem was that as soon as the threading tool touched the part it crawled over the top of the tool. We turned a few hundred dollars of rod into chips and little twisted bits. Then we decided that using 0.925 (sterling) wouldn’t be the end of the world. We got three good screws in the first four attempts.

Levin made screw cutting attachments for their lathes, and I have several of them. In 1984, before getting the OEM Levin attachments, I made my own. I will admit that 1/16-90 is the smallest screw I ever made with one, and that was in 12L14 steel with a knurled head. I have calculated change gear tables for pitches from 10 to 200 TPI and the metric equivalents, so 120 TPI would not be a problem. I wonder if they make 000-120 chasers for the Geometric EJ5 die head. That tool might thread fine silver.

That said, fine silver and 24K gold are not suited for making tiny screws. A little copper added to the principal metal does wonders for increasing yield strength, which is why jewelry is usually made from sterling or coin silver and 10 to 18K gold.

1950's Levin WW lathe with Vanice screw cutting attachment


Larry

 

[mnl]

Now I find out about that. It looks very similar to the one I have for my 10mm Lorch. Of course we were in a bit of a hurry at the time and had to use what we had on hand. There was a specific reason we didn’t want the copper in the silver, reducing the nuclear specific heat. After the fine silver debacle we figured out we could live with the little bit of added copper. Later we were able to source silicon silver which was very nice for making small bits.

 

[mattthemuppet]

For the shorter screws I'd start with a longer set screw than I needed and hold the non-socket end in the chuck with just enough clear to cut off the finished pin. Then use a thin cut off wheel in a die grinder to grind the pin down to diameter and cut it off when finished.

 

[kenton]

A friend of mine showed me this rotary setup for turning on his WEDM.


Something like might work well for Just a hand full of parts.

Edit: a part he made with it out of carbide.

 

[implmex]

Hi kenton:
That's a BRILLIANT idea!
And I even have a wire EDM with a rotary axis.
I didn't even think of doing it this way.
Just goes to show we can all have brain farts and senior moments.
No one is immune.

I owe you one!

Cheers

Marcus
www.implant-mechanix.com
www.vancouverwireedm.com

 

[Mike Hill]

I may have a Levin lathe that I may part with if anyone is looking

 

[mhajicek]

This all reminds me of one of our spectacular failures, trying to make 000-120 screws from 0.9999 silver. Starting mater was 1/4” dia round, which even 40 years ago was $100/ inch. We both a nicely kitted Levin and a couple of HLVHs. The Levin could hit the diameter we wanted a couple of tenths better that the HLVH, but no single point threading, so it was necessary to transfer. The problem was that as soon as the threading tool touched the part it crawled over the top of the tool. We turned a few hundred dollars of rod into chips and little twisted bits. Then we decided that using 0.925 (sterling) wouldn’t be the end of the world. We got three good screws in the first four attempts.

Now try Platinum Iridium alloy.