My z-axis brake seems to be disconnected. As far as I can tell, a 24v and Gnd pair of wires (red/yellow) snake up from the PSU to the z-axis. As that pair of wires pass the control board the red wire is interrupted by a connector socket that is currently floating in space. I suspect that it should connect to pins 3-4 of J5 (schematic location 1D3). Can you confirm that?
I can confirm that! The power supply generates +24V for the Z-Axis brake that is switched by J5-3&4.
Next question, still regarding that brake. The z-axis will move by hand. Is that normal for a machine without power? I would have thought from the schematic that the brake is powered to disengage, and that it should be locked otherwise. Does that suggest a problem with the brake that the previous owner forgot about? Or is it possible that the 45k spindle machine doesn't use a brake and the disconnected connector is simply an unused part of a common harness?
You are correct, the brake is powered to disengage. If you can move the Z-Axis by hand, the brake is not functioning. Remove the brake from the back of the Z-Axis motor and make sure the nut is firmly attached to the motor shaft. The brake locks the nut and the not locks the shaft. Every Benchman machine regardless of spindle configuration has a Z-Axis brake. Otherwise if the machine is not servoing position (think E-Stop pressed, etc) then the Z-Axis will drift down due to its weight.
Still Z-axis, any idea where the way covers came from? My lower cover flops outward and is a mess. I'm guessing it's identical to the top cover that is in much better shape and that I can swap them to provide better protection nearer the cut, but if a replacement were affordable...
That depends on your definition of affordable. If I recall correctly, those covers came from Gore and were relatively expensive. They were built to Light Machines specs and prints so I doubt they would be available anywhere but Light Machines. You could always give them a call and find out. (I do believe they were symmetric).
Finally, my spindle is cooled by a Turmoil chiller, containing a pinkish oil. I'm assuming that it is original spec. Any clues on compatible oils should I ever need to top it up?
I wouldn't ever try mixing chiller fluids. It may work or you may end up with a sludgey mess that requires a full spindle system teardown, clean, and rebuild. Again call Light Machines and ask what chiller coolant is used/recommended.
Note: Light Machines and Intelitek are the same company. I was employed during the name change and always felt more aligned with the Light Machines side of the business.
