A Sting in the Tail

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More tinkering with the lathe today. I have decided to roll with the (very slight) convex curve of the bed as I'm unlikely to ever use the full centre capacity of the thing, and the closer to the headstock you get, the truer it seems to get. As I get better at measuring - indeed get better tools so to do - I'll have a crack at working out just how far out of whack all the various bits are and triage out the urgent stuff: apropos of which I was trying to get the tailstock into something like an accurate state this afternoon, as I still want turn down that bit of steel stock for a second change-wheel spindle; but that old design really needs an octopus to hold everything square *and* adjust the various set screws for the gib and the main setting screws.

As the set-screws and the securing screws are more ancient than me and the heads are chewed to buggery, I'm going to replace them with cap-headed screws to make the going easier, and I'll gradually replace all such antediluvian kit over time. I have got a modus operandi worked out for doing the tailstock adjustment and all I need to do is to make a jig to eliminate the need for one of the eight hands currently required, to hold the 'stock square to the bed, so I can get the centre right. With new, longer set screws in place, it should be easier to pull the thing to the centre of the set-up bar, against which I'll use the old 'Unique' test indicator to show any deflection as the tailstock centre is advanced into the bar's centre. All good fun...

Addendum: I've been worrying about the fact that the tailstock centre is a couple of thou high, and wobbling on about shimming the headstock, when the blindingly simple solution is just to get the tailstock ground by said amount: simple and relatively cheap - doh!

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