Modifications and Improvements to a Unimat SL 1000 Lathe

[Paul Jones]

C-Bag,

Thank you for the encouragement. I like to periodically update the progress and have it in one place. As with any machine tool, once you know its limits and idiosyncrasies, it is possible to do exacting work. The problem with any 3" swing lathe is the depth of cut is much less than larger lathes so the machining takes much longer to complete. This is why I sometimes use my other lathes instead of the Unimat to make parts for the Unimat. It is just faster.

I used this Unimat when I worked as a prototype designer and machinist at the School of Oceanography, University of Washington to help pay for my undergrad education. The shop had fantastic machine tools but the smallest lathe was a Hardinge HLV 11" swing lathe and we needed something even smaller for building some of the parts to the scientific instruments. I bought my Unimat SL 1000 lathe new in 1970 to do this work and it machined perfect parts. Everything had to be made to very exacting standards. We were building scientific equipment designed to sit remotely on the ocean floor at 10,000+ feet below sea level with extreme crushing pressures and temperatures a hair above freezing and to be command remotely and returned to the surface successfully. The most difficult problem in deep ocean equipment was accelerated and unexpected corrosion near the pressure seals designed to protect the equipment from leakage by using multiple o-rings (using two main and one backup o-ring). Most parts were made from stainless steel. Anything made with aluminum had to be soft anodized and machined with no sharp corners where corrosion might start. We discovered hard anodizing aluminum had microscopic surface cracks where the corrosion would get in and under the hard anodized surface. The equipment had to be carefully inspected for reuse because the corrosion was hidden where it was very obvious with soft anodized surface treatments (also more colorful than plain black).

Thanks for looking,

Paul