recently I purchased one of these chinese 3040 CNC Machines. Unfortunately I am having problems with the X-Axis which sometimes is losing steps.
I installed homing switches on all of the axes and Y and Z are working just fine. The X-Axis worked fine the first time, but since then it is always having problems. It moves all the way to the left until it hits the limit switch, but when it backs off to move slower to get the exact position, the motor makes strange noises and is not moving. I then have to manually trigger the limit switch for it to continue.
Here is a video of the problem:
When I decrease the Jog-Rate in Mach3 to something below 5% I also lose steps. Running it between 5-100% works fine, just when I am moving very slow it’s not working.
I ran some small programs on the machine and they worked fine. Even when I was surfacing the MDF-Wasteboard with a 25.4mm (1") bit, there weren’t any problems. However when I was pocketing out some holes to install threaded inserts, I noticed that some of the holes were off by a few milimeters. Some of them were too far to the left, some others too far to the right. So I assume I was also losing skipping steps there.
Inside of the CNC-Controller are these Motor Driver boards based on the TB6560AHQ:
Picture found in this documentation: https://imaginieriecom.files.wordpre…umentation.pdf
What I tried so far:
- manually moving the X-Axis (when the machine is off) to see if the axis is moving smooth – it moves just as easily as the other axes
- Switching the Motor Driver boards – I connected the X-Axis to the Controller of the A-Axis – still the same problem when I am homing the axis
- Getting rid of my USB-Extension to reduce possible sources of errors
- Slightly decreasing the acceleration in Mach3 – but since it occurs on slow movements, I wouldn’t expect the acceleration to be the problem
- Increasing the step-pulse in Mach3 to 15us (was recommended in a video I found) had no effect on the problem
What else could I try? Does someone have the same or similar machine and experienced these issues?
I already searched this forum and got some results, but none for the exact same motor driver board I have.