Grinding noise and intemittently losing steps.

[Conn Fountain]

Hi Jeff.    I built a CNC from Dave Gatton's plans ( and kit).  But I have had issues with  the motors grinding from time to time when I do a fast move on the axis.   I notice this most of all on the y and z axis.

I also have had issues with the unit losing steps when trying to do a long 3d carve that takes several hours.

I setup Mach3 with instructions from Dave. 

I was looking at your site and noticed the dampner videos.  Is there any chance my intermittent grinding is due to some mechanical issue.   I have checked alignment, lubed. slowed velocity and accelation in Mach3 and I am not finding an answer.

I wrote  a program in GCODE  to do 100 moves in the Zaxis moving an inch up and back to zero.     No steps loss in this test.  But If I fast move the z to the top I always seem to get a grinding noise.

I do have a dust collector system that I just connected. So I need to go back and ground that. But this intermittent grinding noise was happening long before I added that.

[Jeff Pollard]

Hi,

  Generally the grinding sound is caused by too fast an acceleration, and the motor then misses steps.  Try slowing down the acceleration and/or top speed of the axis in question again. Also make sure there is no binding on the ways or screws.

  Resonance can cause a power loss which can cause the motor to stall and make the grinding noise as well.

Jeff