is fourth axis indexing done by rotating the a axis by hand or is it done by motors? ie when the xyz axis are moving along simultaneously and they reach a point where the work piece needs to be rotated on the A axis does the xyz pause and the a axis motor comes on to rotate the work and then the xyz motion resumes, or does the xyz pause while the a axis is rotated by hand?
It all depends on how you have your program written. There is software out that will use all 4 axis simual,,,simaul....at the same time! Your machine controller will also have to be capable of 4 axis interpolation to use all 4 at the same time!
edited to add: opps didin't finishing reading your post "by hand", but agian depends on how you have your machine and program set up. I made several parts by writing my programs for each side of the part and then rotate by hand. I now have a motorized a axis and it is much better.
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