Precision and spindle wobble

CNC Machines Nomad
1

I have had my Nomad since September of this year. I have been using it to cut thermoforming tooling out of HDPE. There has been issues with the precision of the cuts along the X/Y axis. I use a 1/8" ball end mill for roughing and a 1/8" square end mill for finishing. I use the recommended feed and speed parameters on the chart provided by Carbide. In MeshCam, I use the automatic tool path wizard and select the finish quality of “Higher Quality” and a Tolerance of “.001 in.”

The tolerance I am actually getting is off from my CAD file by an average of .026 inches on the X/Y axis cuts. I don’t necessarily expect .001 tolerance. But .026" makes my thermoforming tooling not useable. When the spindle starts, there appears to be a visual wobble. Thus, I am thinking there is a runout issue.

Any recommendations on what to try or is there something wrong with my machine?

Thanks,
Jeff

2

Hey Jeff-

If you have runout that you can visually see then that’s a big problem and we’ll get it taken care of. For it to be off enough for you to see it without a dial indicator I think it’s more than likely a chip trapped in there.

If you haven’t done so, remove the spindle collet and nut. Be sure that the inside of the spindle taper, the collet and nut are all free of dirt and chips. Reassemble it and check for runout again.

If it’s still there, and you can see it visually, then shoot a quick video of it and send it to support and we’ll see how to proceed.

-Rob

3

Thanks rob, I will checked the spindle collet and nut. Then I send a video to support.

4

For everyone’s sake. Make sure you read the directions and “snap” the collect into the nut and hear the audible “click” and screw it on to the spindle as an assembly. If you don’t you won’t get proper seating, and you will get run out. A hole with a .125 mill was .152 for a varaince of .027 with out the click. A hole with the click was .126 for a variation of .001.

Moral of the story, don’t be like me!

2 Likes
5

Thanks for the tip! By the way, I learned that holding my work down properly is important. Sometimes its hard to find that partially milled part under something across the room. Oh, and keep that front door shut too. Or, maybe just stay out of the room when I press go??