I work with an older Citizen L20. I had been concerned that the pockets were not locationally perfect, or course I can adjust my diameter centering on the pocket tools, being T22-22 and T31-33. Well, I have placed a 3/4" tool in each pocket, and I can run an indicator and tell that locationally, all these pockets are between .007-.009 above or below center. Since I've not been around these machines but for about 2 yrs, I am concerned that this is too much out of center. I would think not much more than .002, and I would probably live with .003 as what I should expect to see.
Most of my smaller drills and such will walk up to center fine enough to make my part. I was using a .381 reamer though to ream a hole, and it gave me a hole .383, as you can imagine how solid a reamer of that size would be.
I am concerned about the center height of these pockets, and adjusting them out in some way or another. My supervisor wants me to study out lifting the sub-spindle and pocket assembly, and placing some shimming underneath it to adjust to make all the pockets about correct. I am concerned about starting such a task because of my limited knowledge of the machine, and what might arise that I do not know of. I am also concerned about their knowledge at my shop, because as for what I know, I am the only one at the shop who knows much about these machines, nobody else really wants to mess with them.
At one point, I knew a shop that was considering boring and placing a sleeve in their pockets to make them true for the machine, but I never heard the end of it. I'm thinking perhaps the lathe ways are worn out on my machine, and I'm hesitant about shimming the sub-spindle and pocket assembly because if the ways are worn, then I don't see my shimming doing any good, due to the inconsistency of the movement along the ways. I'd like to hear from some others on this. I'm certain I'm not the only one who has dealt with this thing. Thanks in advance.