By the Lathe for the Lathe

 
One of the things I wanted to do was make parts for the machines that are expensive, hard to come by or out of production. Well I had to do exactly that today.
I had ordered this nice little machine vice for the lathes. I will need it (and a growing list of accessories) if I want to clamp stuff for milling and boring.


Unfortunately it doesn't come supplied with mounting bolts or 'T' nuts. I had two 6mm bolts of the correct length but no 'T' nuts.

'T' nuts are small captive nuts that fit into slots on the machines for clamping and such like. The SL and the Mk4 take (what appears to be) different sizes. Go figure.
I carefully measured the two slots and drew up CAD files for both for future reference. The Mk4 had two T nuts with the toolpost so I carefully measured those with a micrometer and a digital vernier. However, the SL only had a poorly fashioned one that had obviously been made with a file, but since it was working I measured that one too.

I came up with a size that would fit both machines, and made a CAD of three different profiles that would all fit. Now I needed something to make them out of.
Ideally I would have preferred to use some 16mm steel bar, but I would need to mill it and I can't do that without the clamp! Catch 22. I thought I might use some M8 bolts who's heads are the correct distance across that flats but I didn't have any. Flat steel bar would have been another option, but I didn't have that either. I came up with two brass 8M bolts who's heads were about 1mm too big.


I decided that they could be hand finished to get them to fit, I also decided to use the Mk4 to see if my efforts with the chuck had worked.
I faced them both off and turned the shoulder down to the correct diameter and thickness.


The next operation is to centre drill them.


Then drill them out 5mm ready for the M6 thread


I then turned them around in the chuck, parted them off and faced the backs.


I tapped them to 6M and then filed about 1/2 a mill off each face with a hand file. Not pretty but good enough so that I can use the vice and mill the next set!


OK, so it's not much to shout about, most engineering students could do it with their eyes shut, but I'm teaching myself as I go along here, so I'm chuffed.
Here they are in the vice and mounted to the cross slide.