Mill Cut internal cylinders with vertical axis cnc rotary table.

[jferguson4]

I have a 3-axis Sherline cnc mill to which I've recently added a cnc rotary table.  I want to cut vertical cylindrical holes by positioning the work-piece using the X and Y axis and power rotating the table to cut the cylinders. 

I

I have to add the 4th axis stepper driver to my self-built controller, and teach myself how to do this; time, lots of time, but I have it.

I can add the stuff the post needs for the 4th axis with Gpost.

Question is simple. Is this possible?  

john ferguson

[bmuller · Accepted solution]

That should be easily doable. You will have to use the post generator program of gpost to get a post that matches your mill. Manufacturing doesn't require a special license for 3+1 machining, which is what you are describing.

[jferguson4]

When it comes to setting this thing up,  3-axis mill with rotary table, it appears that this is not really a 4 axis mill but a mill-turn machine since the x,y,z cuts are 3-axis, but using the rotary table to cut the cylindrical surfaces is actually mill-turn (I'm turning the work-piece just as if it was chucked up in a lathe.) and when I set up my work-center, this is what i needs to tell creo - mill-turn.

Does this make sense?

[bmuller]

If you plan on cutting while the rotary axis is turning, you will need a full machining license. If you are just positioning to a rotary location and keeping the rotary axis fixed while machining some feature, you don't need a full license. The mill-turn is for machines that can do turning operations and milling operations on the same hold, which doesn't sound like what you have.

We originally had just the prismatic milling package, and 3+1, (i.e., rotate, lock, cut, etc.) was easily doable. We only needed to get full machining when we decided we wanted to cut while the A axis was moving. I am not sure why I had a different experience from Ken Farley.

An easy way to check: set up a simple part with the machine coordinate system. Do a sequence with a sequence coordinate system oriented differently from the machine coordinate system. Check the generated CL file. If the CL file has a MULTAX and GOTOs have 6 numbers (3 for position, 3 for tool orientation), you are in business.

[jferguson4]

Thanks you so much. I was pretty sure this could work, but before I spent all the time, I wanted to make sure.

[jferguson4]

It was a nice idea, but apparently my manufacturing license will not support a mill-turn setup.  I'll do it by hand. Nuts.

[KenFarley]

Ah, yes, we had a similar problem. Wanted to do psuedo 4th Axis programming (rotate table, lock, machine, rotate to next position, lock, etc.) and found that 4th axis programming is only available if you have the 5th axis license. So, had to program the code for each position and hand edit in the table rotations. What fun.

[jferguson4]

what a disappointment.  For the number of times i would need to do this, I cannot justify the cost.  I suspect the G-Code for this would be very simple, repetitive, but simple.  But then doing it manually would also be simple.

fortunately, this is a hobby not a revenue source, and I don't really have to fix this lens that Nikon didn't think enough about when they designed it.  A bigger lathe would also work, but I'm out of space.

nuts.