Senior 3C Mill - head info reqd. pse.
Posted: Mon 24 Aug , 2009 23:40 pm
Senior 3C Mill (s/n 3C24037B, manufactured April 1987) - head info reqd. pse.
Appreciate if anyone can provide info on :
a) Z-drive motor. After repairing the intermittent Z servo tacho wiring, the quill has started "stuttering" and on inspection its at a regular interval which corresponds to one bout of stuttering per rotation of the Z servo motor. Now traced to what I believe is a shorted commutator or failed winding on the Z servo motor (with the motor just on low-voltage a DC supply it will turn through, say, 330 degrees and then jump the remaining 30 degrees). Am urgently trying to find a replacement or to get it rewound. No label on it. Appreciate if anyone could advise - anyone have a parts list? or just the motor specs? or even better, a user manual? or even just recognise the maker? (no label on the motor at all, castellated top may be distinctive? appears tacho is an integral fitting, appears to be remains of a Baldor label on one of the other larger bed servos ....). Base appears to be NEMA-34 footprint. Current motor (2 brushes) delivers app 30 RPM / volt (minimum start voltage is just under 3v); free-running/no-load current (i.e. motor off machine) is app. 0.2A. Tacho (4 brushes) gives out app 6.5v / 1000 RPM.
b) Quill - for a while have been concerned that the bottom of the quill feels warm after use. The Bijur system doesn't extend to the head, just a drip lube on the Z ballscrew, nothing for the quill or spindle itself. Is there supposed to be any way to lube the spindle bearings?
c) and just out of curiosity - has anyone ever fitted a power drawbar to a Senior 3C? ( I know some folk use the Coventry 'Easychange' but would like to have power drawbar which opens avenues for possible eventual ATC?)
thanks / Dave
Appreciate if anyone can provide info on :
a) Z-drive motor. After repairing the intermittent Z servo tacho wiring, the quill has started "stuttering" and on inspection its at a regular interval which corresponds to one bout of stuttering per rotation of the Z servo motor. Now traced to what I believe is a shorted commutator or failed winding on the Z servo motor (with the motor just on low-voltage a DC supply it will turn through, say, 330 degrees and then jump the remaining 30 degrees). Am urgently trying to find a replacement or to get it rewound. No label on it. Appreciate if anyone could advise - anyone have a parts list? or just the motor specs? or even better, a user manual? or even just recognise the maker? (no label on the motor at all, castellated top may be distinctive? appears tacho is an integral fitting, appears to be remains of a Baldor label on one of the other larger bed servos ....). Base appears to be NEMA-34 footprint. Current motor (2 brushes) delivers app 30 RPM / volt (minimum start voltage is just under 3v); free-running/no-load current (i.e. motor off machine) is app. 0.2A. Tacho (4 brushes) gives out app 6.5v / 1000 RPM.
b) Quill - for a while have been concerned that the bottom of the quill feels warm after use. The Bijur system doesn't extend to the head, just a drip lube on the Z ballscrew, nothing for the quill or spindle itself. Is there supposed to be any way to lube the spindle bearings?
c) and just out of curiosity - has anyone ever fitted a power drawbar to a Senior 3C? ( I know some folk use the Coventry 'Easychange' but would like to have power drawbar which opens avenues for possible eventual ATC?)
thanks / Dave
- 1 - Senior 3C Z servo motor
- 1 Denford_3C_Z_Servo.jpg (148.16 KiB) Viewed 11316 times
- 2 - Senior 3C Z servo motor tacho
- 2 Denford_3C_Z_Servo_tacho.jpg (148.13 KiB) Viewed 11316 times