I've had a generic Chinese CNC machine for about 2 years now and generally its been 'just ok' ..
Haven't used it very much, maybe a total of 50 hours over the 2 years, so basically still new.
The problem I am having with it, is that during the machining process the stepper motors will randomly stop/jam for a few seconds then go again.
When this jam happens, the software continues to send data to the controller and gets out of sync with the actual machine.
Then when the steppers start working again, it has skipped a whole section of the job and just makes a mess of everything, resulting in a waste part.
My question is:
What can cause the steppers to simply stop/jam like this and is there something I can do to fix it ?
Any help would be very appreciated ..
Here is a short video of what I am trying to describe ..
EDIT: This is the only information I have on the CNCest Machine (From Ebay seller)
4Axis-6040-1500W
cnc engraving machine parameters:
X,Y,Z Working Area?600(Y)*390?X?*120(Z)mm
Outside dimension?865*680*570mm?L*W*H?
Table size?770?Y?*490?X?mm
Lathe structure?6061/6063 Aluminium alloy
Max. Feeding height??100mm
Drive unit
X axis?1605 Ball Screws
Y axis?1605 Ball Screws
Z axis?1204 Ball Screws
Sliding unit
X axis?High intensity Chromeplate shaft
Y axis?High intensity Chromeplate shaft
Z axis?High intensity Chromeplate shaft
Stepping motor?57 two-phase 3A 150N.cm
Spindle motor?tips?1,The spindle motor must connect with the VFD.2,It cannot directly connect with the supply voltage (AC220V).3,Please don’t change the data setting of the VFD if you are not professional technicians, or it might damage the spindle motor.
Outside dimension?65*158mm
Material?304 stainless steel?Copper coil?Pressure cast aluminum pipe water jacket
VOLTS?current?power?AC220V/60Hz?5A,1.5KW VFD
Spindle speed:24000 rpm
Max working frequency?400Hz
Principal axis collet:ER11collet?Standard configuration :6mm
Nut Model?ER11-A
Cooling?Water-cooling
Speed mode ?By adjusting the VFD output voltage and operating frequency from 0-24000RPM
Lubrication way?lubricated by high grease
Repeat accuracy?0.05mm
Carving Instructions?G code / TAB files / nc file / NCC files
Software environment?Windows XP/win7
Maximum speed?0-4000mm/min
Carving speed?0-1500mm/min(different materials differ?
Control box parameters:
Operating Voltage?AC220V
Control unit?Toroidal transformer + PWM power supply module + TB6560 stepping motor drive
Command code?G code
Acceptable software?Mach3,EMC2
Protection?Emergency stop button
Hi Sobo -There are two things that will cause this issue 1) the acceleration setting is too high so as the machine tries to achieve the set accel it can't and stalls 2) there is a mechanical issue with the drives creating extra friction that creates the stall.
1) set the accel very low and slowly work it up and see what happens
2) check all mechanicals on the drives that stall. Something will be loose or tight or worn
Peter
Check the nut at the end of the shaft, sometimes they jam against the bearing. That's the problem I had. Just watch them rotate, if the nut hits the bearing it will jam, just loosen the nut until it doesn't touch the bearing.