I am setting up a used G0704 and while squaring the vise to the table along the X axis with a indicator touching the back of the vise I am getting .0015 movement on the Y axis as the vises moves along the indicator. Any idea what might cause this
We need a bit more clarification on the process you are following.
the correct way to zero a vise:
1. align the vise square to the table slots as close as you can,
2. tighten down the right bolt, gently snug the left bolt
3. Starting with a DTI in a holder attached to the quill at the right side of the vise, with the DTI riding on the
inner face of the FIXED jaw of the vise
4. Move the X axis so the DTI sweeps the vise to the left side of the vise
5. tap the vise gently with a plastic hammer until the error on the DTI reached zero. It is common to have 0.030" or more error in alignment at this point.
6. Repeat the process until you are within 0.002".
is that what you are doing?
The slots on the table don't actually have to be squarely aligned. You align the vise to the quill and the travel of the table, not the slots in the table.
You must be using the fixed jaw of the vise for alignment.
I am getting .0015 movement on the Y axis as the vises moves along the indicator
EDIT: i misread your post, thinking you were talking about 15 thousandths variation (0.015").
If you are talking about 1.5 thousandths of an inch (0.0015") than you are done. You can dial it in closer (I can get it to less than 0.001), but it is really kind of a waste of time. The mill will deflect at least that much during normal operation. If your operation requires you to be accurate within 0.001", than you are using the wrong machine (surface grinder will get you within 0.0002" without much effort)