Avoiding pivoting pitfalls
It is always difficult when repivoting or making a new arbor, while turning the pivot diameter to that which is required not to dig into the shoulder or face as it is being generated. It is not always possible to skim up afterwards because the shoulder length dimention is then gone.
The simple way to avoid this condition is to mount a dial indicator on to the side of the headstock, drill and tap a 5mm hole and bolt it into position using the mounting lug beneath, packing it out with sawn-off tube or an assembly of nuts.
You now have a very accurate depth indicator indeed, along the bed length.
I always allow about one full turn of the needle and zero the indicator at the shoulder position. I have found that a one-thousandth dial is the best for this anyway. Whatever was wrong with one thousand equal divisions equals 1in?
William Maysey, UK
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