Modifying the spindlenose
The main spindle of the machine has – as its common for a grinder – a tapered spindle nose and a thread to hold the wheelhubs in place.
Unfortunately I have only one wheelhub for the Knuth grinder. But I have about 12 wheelhubs for my d-bit grinder and the surfacegrinder which share one common taper.
So the decision to modify the spindle of the Knuth grinder to accept the same wheelhubs as the d-bit grinder and my surfacegrinder was very easy. The modification was planed in a way that still allows to use the original hubs.
I took the compound slide of my lathe, clamped it to the table of the grinder and turned down the end of the spindle to the same taper as my other two grinders.
Care was taken to match the taper very precisely and keep a very fine surfacefinish on it.
The end of the spindle needed to be drilled and tapped for a M6 thread which is needed to hold the wheelhubs in place.
The drill is held in a 5C collet block.