I thought I'd throw this out to some of the CNCZone Okuma lathe experts. Our LC-20 was pulled out of moth balls about two years ago after a brief stint in the warehouse while our addition was being built. Since it's return we have mainly used it for chucking 5-6 inch casting with a tolerance of +/- .005. It's worked well in that role. However we occasionally will throw a threading job at it. It has an OSP 5000 control. We used to program using the G71 F and J without a problem. Since it's return we've noticed a .002/.003 lead problem per thread progamming it that way. We went to G33 and input the feedrate so it can be adjusted to give us a correct thread lead. This worked out fine until one of the operators told a vice president about the problem. He issued an edict to get it fixed. We had the Okuma tech in. We ran several threads sizes while he was here, all with the same results. The machine seems to run the threads consistent but the calculations just seem to be off. The Tech's involved are scratching their heads and after consulting with the Guru's at Okuma have suggested changing the threading encoder first to see if it has any effect. I don't mind dishing out $600 if it will fix the machine but my budget can't take trial and error. Up until I discovered the CNCZone I would have no choice but deal with it. Has anyone had a similiar problem or can anyone offer suggestions to correct the problem.
Thanks,
Gunner