Member postings for Dave Martin

Denford Senior 3C Mill (s/n 3C24037B, manufactured April 1987) - appreciate if anyone can provide info on the Z-drive quill servo motor.

The quill has started "stuttering" and on inspection this is 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 a non-CNC low-voltage 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.

Unfortunately there is no label or markings on the motor at all.  Denford have searched but it just predates the start of their archives; have also drawn a blank via the Denford forum. 

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. 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.  Half-inch shaft protuding 1.5".

 

thanks / Dave