Yeah, "matched" in my mind meant two vises of the same model. I realize it is possible to order new vises as a pair from Kurt with precision matching for extreme accuracy, I'm never going to be working at that level of precision.You dont need a matched set of vices, buy a used pair and tweak them , about the only difference you would need to worry about is height.
I saw good used Kurt vives at HGR last week
By that logic, I don't *need* this mill. But I like it. My other mill is set up much like you suggest, 6" rotary on one side, 6" vise on the other. The rotary I have for this is a 16" K&T so it isn't tiny at over 300lbs. My lathes are D1-6, sort of a weird mount to adapt to a rotary but I suppose it could be done.My advice: you do not need multiple new vises.
Haven't file checked it yet. Pre-concept stage only so working on this. The problem with the washer concept is that there is a bit of geometry to the underside of the bolt that goes with the arbor. Of course shortening the arbor alone doesn't solve this. I have a lathe or three so turning a complex washer is certainly possible. The lathe is just in the other shop so I'll be doing some running back and forth. I'll be back at the shop with the mill tonight, and will start pondering all of the details at that point. And may have to bring the cutter and arbor back to the shop by the house to have it in hand for the lathe work. New shop hopefully soon, all metalworking in one place.I wonder how hard the arbor is? File test?
Do you have a CBN tool if the arbor is too hard for carbide?
Could a special "C" or "hat" section washer (on the screw side) straddle the .050" extra arbor length?
I would suggest making a washer/spacer rather than modifying the arbor. YMMV