Hi Guys!
I started a new project, a retrofit of a Hermle UWF 700. It was made in 1984, 40 years ago. The mechanical condition is very good, no signs of wear anywhere, although that might also be due to the automatic lubricator. The mill has a 18-speed gearbox, maxing out at 2000rpm's. The electronics were not working anymore, so I only got the machine itself. I did get a lot of nice documentation however. Tool clamping works by a hydraulic cylinder. The gears are lubricated with an oil spray system with a seperate oil pump.This is what the Hermle looks like:
And inside my small shed:
The ways still look pretty good:
I paid 2000€ for it, which seems fine.
My Plans:
- I want to use Servos for the three axis. I am currently thinking about 660 Watt JMC servos or some chinese ones, since I can not get my hands on anything else.
- The machine already has glass scales on all three axis. I think it should be possible to use them with a mesa board if I use three Heidenhain EXE 602 E and use them as feedback in a PID loop.
- I have a 7i96s with a 7i85, which could be able to do the trick If I use the step/dir interface of the servos, which only works in positional mode. But I read multiple times here on the forum that velocity mode is better. Otherwise I will buy something like the 7i97T.
- I might increase the low spindle speed by using a belt drive, at least 4000rpm would be nice.
- I might use an Arduino to shift the 18 gears of the gearbox. That seems simpler to me rather than using LinuxCNC to handle the shifting.
I will post updates from time to time.
Manuel
