Ancient Knee mill retrofit

[kong]

Problem solved (well, fingers crossed anyhow!)
There seemed to be some noise due to the use of the err/res detection circuit. So unplugging the wires from the gecko's to this circuit cured the problem. I just hope thee are no more issues when I start the motor!

[Macaba]

There may be some that still remember this thread, so I thought I'd give an update:

I'm the new owner of this project.

Since getting the machine, I have:

Gutted and rewired the control box.
Modified the Z-axis ball nut housing with more heavy duty grub screws.
Found the source of the 'noise'

The 'Noise'

The noise was nothing to do with the control box as I initially suspected. I had rewired it, paying attention to good practices to reduce crosstalk and capacitive coupling. The 'noise' was still present.

It turns out it was a far more simple problem. The Z-axis motor employs some sort of diode configuration to ensure its correct operation. There was a ground lead to this, crucial to its correct operation and this ground lead was connected to the chassis of the Mill.

HMM! I thought. The chassis of the Mill was actually floating with respect to earth. So... to my eternal relief, I simply reattached the wire to Mains Earth... and the machine works perfectly.

Let this be a lesson to you all to ground properly

Comments appreciated.

Macaba

[Macaba]

I need some help.

I am thinking of counter-balancing the weight of the quill with a cable and pulley system (simplicity wanted!), and I would like some good suggestions as to what the likely weight of the quill of this zenith knee mill is. All I can guess is HEAVY!
Once I have an idea of the weight, I can then look at cable guage, pulley sizes and what it is going to be supported by.

Thanks for any help you can give