i recently came across a good deal on an old shizuoka vertical knee mill. I stripped the NC controls and tool changer. It was originally used to machine cast iron. Because of this, there is iron powder mixed with old coolant that has formed a cement like coating on most on the machine. I plan on converting the maching to CNC but before i do that i want to overhaul the machine.

1. What problems/concerns should i have with rebuilding a mill?
2. Is it worth stripping both tables sandblast and paint?
3. Is there an easy way to inspect ballscrew backlash without removing the tables?
4. Should any precautions be made when removing the tables?
5. How are the ways inspected and should i sandblast ground surfaces that have the powerdered iron or try another removal method?
6. Hs anyone else done a mill rebuild any tips?

Thanks

I would strip it right down, but do not sand blast any ground surfaces, if they are pitted you may have to get them re-ground, if you are lucky the ways would still have the original lapping marks, look for scoring though, where the dust may have got in, if it is caked cast iron, it may chip off with a soft tool.
To test for backlash Without any control on it, put a dial gauge on the edge of the table and turn the ball screw/table into the gauge, zero the gauge and then turn the ball screw in the reverse direction and keep track of the amount you have turned the screw until you see the gauge just start to move again. The degree of BL can be calculated from using the pitch of the screw and amount turned.
All the lube point metering units should be replaced while stripped down, and the lube lines flushed and the pump cleaned out, lube oil turns to jelly in the bottom of the reservoir.
Al.

thanks for the advice