Centroid Community CNC Support Forum

the "reversing" selection refers to rigid tapping. "reversing" mean that the spindle is reversing at the bottom of the hole not a tapping head.
tap in wax or plastic first!
from the write up" Test Tap holes in machinable wax. Using wax as a test medium does two things. It saves the tap from breakage but more importantly also quickly exposes bad threads better than metal. So using wax is critical to dialing in the rigid tapping parameters where if you tapped in metal the test results not be so obvious when fine tuning. For instance, if the Z axis was pulling out of the hole a little too soon and running ahead of the spindle this puts stress on the threads in metal this might not show up as a problem at first..but in wax the wax threads will give way at a much lower force than metal and it will be obvious that things are not perfect. If rigid tap parameters are not set perfectly you will not get good threads in wax and if you are getting good threads in wax you will get good threads in metal. PVC and some other plastics can be used as alternatives to machinable wax but wax is preferred for fine tuning Rigid Tapping.
Use Centroid’s Intercon Conversational programming to program the test tapping program or download sample ¼-20 Rigid Tapping Intercon programs for Mill and Lathe here. Notice the programmed tapping RPM is 640 RPM and the spindle is in hi range.

Use the trouble shooting guidelines below to adjust the Rigid Tapping Parameters as necessary for good results in wax.

there is no reason a dc spindle drive won't work as long as you have good acell decel times and can control CW and CCW.
that being said there are some really nice small ac motors and vfd's available these days.
check out Kai's build, he decided to go with AC spindle motor for his lathe..looks like a good move.

Thanks, Keith. I’ll look into it. Regarding CW and CCW, from what direction are you looking at the chuck? If the tool is on the front side, is CCW the normal/forward rotation?

on a horizontal lathe....with the spindle spinning CW... while standing in front of the machine perpendicular to the z axis (bed) looking at the chuck.....the top of the chuck is spinning towards you.

ScotY wrote: ↑Tue Jan 02, 2018 9:29 pm Regarding CW and CCW, from what direction are you looking at the chuck? If the tool is on the front side, is CCW the normal/forward rotation?

The way I look at it Scot is from the back side of the headstock...where the pulleys, gears & belts are. Clockwise (M3) is the normal direction on your mini-lathe & counterclockwise (M4) is reverse. HTH

Rotation is viewed when looking down the axis in the + direction. This is true for any axis..

cnckeith wrote: ↑Tue Jan 02, 2018 9:15 pm tap in wax or plastic first!

Been doing this for years and actually never thought of this...

Clay

Thanks, guys...great help!