Might be Stellite Colin

>gasp<

Pure unobtainium!

Neil

Based on the dimensions and weight that you give the density works out at 7.95 g/ml so it is definitely not an exotic heavy metal like tungsten which has a density of 19.3 g/ml. The density 7.95 g/ml is very close to that of iron (density 7.87 g/ml) so I think it is likely to be a ferrous alloy. However, the lack of sparking when touched on a grindstone is strange for a hard ferrous alloy.

Mike

hi The carriage is possibly magnesium and plated with electroless nickel,Early files with linear actuators,used ball slides on hardened steel rods ,later on ball races ran on hard ceramic rods ,though a number of files had rotary actuators, ,I never saw a bar as you described in a Hursley designed actuator, How big are the discs in this file? I have never seen the original US designed Winchester file. Lots and lots of problems with all files as one might expect in leading edge technology, Regarding mechanical manufacture,one problem were the very tight tolerances required,and it took a long time before very good cnc machines were available not only to reliably achieve the tolerances but to also make parts at an economical cost.Thermal expansion is another problem ,files used to get hot and expand and the design has to cater for the heads to register with the disc tracks within a temperature range. Your rod is the brainchild of some scientist somewhere and unless you had the dwg and specification you will have trouble finding out what it is,as there were many wierd and wonderful parts and materials used in files.

I worked on this style of disk drive in the late 70's. I worked on repairing them and regular maintenance. Every 3 months or so we had to replace absolute air filters and check the head alignment against a reference disk pack. This would take a couple of hours. I had nothing to do with the manufacturing so I do not know anything about the materials used. Here is a link I found on the web to a service manual for one of this type of disk drive. These were removable pack drives not Winchesters. The manual shows the type of linear actuator used to position the heads. It was driven by a giant loudspeaker voice coil.

Les.

Try grinding it on a green disk to see if it cuts

Bri

That's an interesting arrangement for a high-precision slide. It could be an economical way to make slides for something like a 3D printer which needs low friction and precision without having to take heavy loads.

Neil

I always like to see the old spec sheets for hardware like that. I have a couple of Easi-Disk stand-along RS232 driver floppy drives, as used fro driving CNC machines and other processes without a computer!. They still work. I found them at a boot sale, left by someone who had just abandoned their stuff in the rain. I thought teh cases would eb handy, abut I eventually tracked down a manual on the net.

Neil;

Not sure why I have three posts the same?

Sorry I just assumed you had a green wheel. 

The bar looks like Hepco linear track which is pretty hard.

bri

Edited By Boiler Bri on 03/08/2014 20:05:40