Mounting stock. 3 jaw or 4 jaw chuck and fixed steady use.

[NigeParticipant @nige81730]

I went back to my rusty bolt last night. The first photo shows how I set it up and I made it as concentric as I could measuring outboard of the steady. You can see the ring of oil where I first closed the steady up, with it as close to the chuck as possible, before moving it to the position you can see. I used a 1 thou feeler gauge to leave me a little clearance in the steady and kept it oiled. I ran the lathe at about 200 rpm and had no untoward noises from either the work or the steady then drilled into the end with a centre drill.

I then put a revolving (live?) centre on the end and set about machining the thread off. The interrupted cut didn't cause any vibration of nasty noises. The tool is an HSS one I ground and tarted up before I started and I was only taking 0.1mm cuts. The steel didn't appear at this point to be too hard but it was difficult to tell with the interrupted cut.

Once I had removed the thread I turned the bar in the lathe,checked it wasn't too far of concentric and centre drilled the other end. Once the end was centre drilled I removed the steady and supported the end with the live centre again. At this point It would have been better I think to have been able to turn between centres but I don't have a face plate or drive dog and couldn't think of another way of holding it.

This time I was working on the 'naked' outside of the bolt. I had been warned by a friendly phone call that the outside 'skin' of the bolt might prove to be hard, tough, horrible to turn (pick any or all that apply) but in the event I wasn't able to recognise too much that was horrible about it though the surface was looking a little rough. However, a resharpen and honing of the tool improved matters though it might well be that by the time I got to that point I was through the rubbish outer layer and on to nicer steel.

I got bold with my DOC and wound up the speed to 400 RPM and 0.2mm of cut. I know. not really a lot but I did get some nice dark blue swarf chips So that is how it sits at the moment, next move is to try and improve the surface by changing to maybe a rounder nosed HSS tool and then trying a Carbide tip and winding the speed but would appreciate any thoughts on that.

Inspection of the bronze supports in the steady showed no damage and just a very slight bur which is no surprise really considering the state of the surface of the piece though I had attacked it with emery paper prior to mounting it all up.

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