Un-lobotomizing a Maho MH600T

Quite some time since the last update. And I have put in a bit of work on the Maho as well. And struggled a bit with the linear scales.

The first step was to get all axes moving under power, and that was easy enough. The following was to install all linear scales and do a bit of cable routing through new cable chains instead of through the old hoses.
 
 

I installed a VFD for the main motor on top of the ram and fixed communication to it through Modbus and Mesa PktUART. I struggled a bit with that because of what I would say is a bug in the Mesa Modbus driver. There is a separate thread with that discussion
forum.linuxcnc.org/27-driver-boards/5432...v2d-firmware?start=0
Anyway, the VFD control of the motor now works.
 

I wired up almost all of the rest of the electrical equipment. The gearbox, hydraulic pump with sensors and so on all work, but still need configuration to work from the GUI buttons or G-code. I haven't decided yet whether to use the gearbox component from Rotary SMP. It expects some gearbox "search direction" inputs which are not present on my Maho. There are ways around that problem, though.

The linear scales have given me all kinds of issues, including:
 - approximately 0.5V voltage drop over the miniature circuit breaker, causing the scales to receive too low voltage and give too weak output signals
 - bad connection for the onboard fuse on one of the boards, also giving high voltage drop
 - mixed up negative/positive connections for the sin/cos/reference signals
 - a lot of noise when measuring the signals with an oscilloscope
After resolving those issues, I got everything working, except for the index signal on the vertical axis. That works erratically. I decided to order an EXE 602E interpolator to test, and with that one it works. To avoid getting stuck here, I ordered two more EXE 602E for the other axes. I haven't given up on my own boards though, but they may require a redesign to work in these conditions. Below a photo from the equipment during the height of troubleshooting.
 
The reason for the issue with the vertical axis is that the reference signal is a bit weaker and barely passes "0V" on that axis. Below oscilloscope traces of the X, Y (ram) and Z (vertical) axis. It might provide useful for somebody.
 
 
 

The machine is basically usable already now if I needed to. But I will try to finish all else than the operator panel before taking it into use for real. Because of upcoming work trips, progress will likely be slow again for a couple of months.