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Core Pins on a Vintage South Bend

jdleach

Stainless
Joined
Sep 19, 2009
Location
Columbus, IN USA
Due to a brutal work schedule over the past few years, my ability to get out to my Shop has been greatly curtailed. Between my involvement in the community, and a second shift, unlimited overtime management position,"fun" activities had to become a very low priority. However, I decided to take a sabbatical from work, and left the supervisory position I had at a local shop in the last week of 2018. Since January of this year, I have only been to the Shop a few times, the latest visit was a little over a week ago (plan on going out tomorrow to spend some quality time with the machines, do some maintenance, clean-up, etc.).

During my last visit, I had to turn out three core pins for a close friend (owns a mold shop). Pretty simple job, pins were 2.011" long, head diameter of .750", with the body being .625 -.001 to -.0015 inches. Since the material was 4140 pre-hard, the best lathe I have for the job is my 1978 Rockwell 12". My favorite lathe though, and most accurate, is my 1931 South Bend Type "O" with the 10' bend. Could also have used the little 1948 Logan, but the wear is pretty significant on that machine, and I need to take the electric motor apart and clean out the ingested dust from decades of polishing (gets hot). The South Bend isn't the best choice, due to it's low spindle RPM. That said, if one has the time, and is inclined to do a bit of polishing, sterling work can be done that is virtually indistinguishable from that performed on a more modern machine.

Since I had the time, and was so inclined, I chose the S.B.

The first task was to clean the dust and a bit of flash rust from it. Lathe was in pretty good shape, although I need to re-level, as I noticed a tad bit of taper when turning the pins. After about an hour and a half oiling and "running" in the machine (after sitting for months on end, I like to run a machine for a period of time with no load so as to work in the oil, and observe for any irregularities). Due to the slow spindle RPM, it took me about 2 and 3/4 hours to complete the pins. They came out dead nuts, and looked beautiful.

It is always extremely gratifying to do good machine work, but especially so when doing it on a vintage machine tool.
 

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Thanks John. Seems I have had this issue before (upside down images) on PM. Can't remember that I ever resolved it. Only occurred with some images, almost random. My PC renders them correctly, but they are borked when displayed on the forum.

Was rather interesting turning out those pins. Had to remember how to use the mic stop (gotten VERY used to a DRO), and get back the "feel" when stroking off the last few tenths with the file and bench roll. Over the last 20 years or so, I would just adjust the tool comp, and hit the big green button. Ain't nothin' in the Shop like that. In point of fact, outside my calculator, I don't think there is more than 4 or 5 buttons in the entire building.

Wait! I forgot, there is a push button telephone. :)
 








 
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