[Shwagiedo]

Hello all i have a HF 7x12 mini lathe i have converted into cnc. I have taken back lash measurments and compensated the backlash in mach3. I am trying to turn the edge of a 1-1/16 socket i am using the NFS turn wizard to turn this socket. My Z axis is hitting its mark every time on the part. But my X axis is not cutting to the depth i have it programed for. I have checked and rechecked my travel/backlash in the X axis and it hits its mark every time, but my part is not cut to the depth i programmed. Could this be deflection in the socket ? Or maybe there is a problem with my machine setup? Should i have a follower rest behind the socket? Any help would be greatly appreciated. I will try to post some pics of my machine later.

Thanks for reading.

[Shwagiedo]

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[ninefinger]

The first issue I see is how you are holding the part (socket). You've been lucky it hasn't come flying out - the length you're gripping is mighty short...
2nd is that a socket is some pretty hard and / or tough steel. You will get a lot more deflection trying to cut it versus a similar size piece of aluminum.
You don't say how much is it off by? Is it repeatable, does it happen with a different material? Answering these questions will help determine if its inherent to the machine or that particular setup (ie tough material)
Mike

[pippin88]

The convention with lathes is Z is the long axis, and X is the cross slide.

[Shwagiedo]

Sorry it took me so long to get back to the post been working doubles all week. Yea the chuck is too small I got a larger one on order and waiting for it to come in, I did have a steady rest on the socket but removed it for the picture. the cut is off by .05, I have not tried it with any other material at this time. If I rerun the program I end up with the same results its not like it takes a little more off each time, I know the socket is tough material and thought there would be some deflection but is this a normal amount ? I did check my saddle this morning and found a little play, I took the play out and will try the run again when the new chuck shows up. The Stepper motors are labeled wrong because I swapped them for trial and error testing when setting up mach and im just to lazy to swap them back lol. Thanks again for checking out the post and replying.

[Fastest1]

On your X are you working in diameter or radius mode? How deep was the cut supposed to be? How far was it off?