Originally Posted by
WallaceLau
Hello everyone!
We are close to buying a 2001 DMU-50 Evo. I don't know much about DMGs but I went and inspected one anyway. The axis moves very smoothly and the spindle is quiet; run-out, backlash, tramming looks good, but when it changes tools it makes a LOT of noise... The machine sounded like a buzzer gone off twice, with what almost sounded like grinding noise in-between. The dealer explained to me the buzzing sound is from the hydraulic system releasing and clamping the tool, and the grinding noise is pressurized air escaping from the spindle (the air is oil-mixed which lubricates the spindle and prevent rotational-induced vacuum from sucking coolant into the spindle housing). If I put my head close to the spindle during tool-change (yeah, stupid of me, I know) it does sound kind'a like those rapid "flap-flap-flap" noise that someone taking a big balloon and slowly letting air out.
Can anyone confirm the above claims? This machine seems well-maintained, and if everything checks out we would like to go through with the purchase. But I really would like to avoid a bunch of unexpected repair bills...
Oh also, one of the button in the keyboard is not working, anyone know where to find replacement keyboard and how much it will cost? I unfortunately don't even know where to look... my Google-fu is lacking today. Any hint will be greatly appreciated!
Thanks,
Wallace