I'm retrofitting a mill made in 1990, replacing the old DC brush servos with smaller, lighter, more powerful closed loop steppers but the bolt patterns are different.
Old motors SEM MT30M4-59 http://www.sem.co.uk/fileadmin/data/...ata_Manual.pdf
4 HOLES M8 x 1.25 - 6H x 13 DEEP ON 75 P.C. DIA. around a 60mm hole through the plate. 60mm is the dimension from the PDF, dimension is NOT critical as long as it leaves enough inside the bolt circle for strength. Threaded holes in the plate don't have to be metric.
New Motors NEMA 34 Sanyo-Denki PBM862FXK20-M
4 HOLES 5.6mm +-0.2 on a 69.6mm +-0.25 square.
73.025mm +-0.025 by 1.5mm +-0.25 recess.
Outside dimension of the motor is 85x85mm
Need threaded holes to duplicate the old motor's bolt pattern plus big hole in the middle to ensure clearance for shaft adapters/extenders. Clearance holes and recess for the NEMA34 new motors.
Plate thick enough to thread into for old pattern and for countersunk socket head screws to mount to the new motors. I don't expect the threaded holes will need to be as deep as in the old motors since the new ones are much shorter and lighter. The mounting areas of the castings are only 1/4" thick with slotted holes.
Old motors SEM MT30M4-59 http://www.sem.co.uk/fileadmin/data/...ata_Manual.pdf
4 HOLES M8 x 1.25 - 6H x 13 DEEP ON 75 P.C. DIA. around a 60mm hole through the plate. 60mm is the dimension from the PDF, dimension is NOT critical as long as it leaves enough inside the bolt circle for strength. Threaded holes in the plate don't have to be metric.
New Motors NEMA 34 Sanyo-Denki PBM862FXK20-M
4 HOLES 5.6mm +-0.2 on a 69.6mm +-0.25 square.
73.025mm +-0.025 by 1.5mm +-0.25 recess.
Outside dimension of the motor is 85x85mm
Need threaded holes to duplicate the old motor's bolt pattern plus big hole in the middle to ensure clearance for shaft adapters/extenders. Clearance holes and recess for the NEMA34 new motors.
Plate thick enough to thread into for old pattern and for countersunk socket head screws to mount to the new motors. I don't expect the threaded holes will need to be as deep as in the old motors since the new ones are much shorter and lighter. The mounting areas of the castings are only 1/4" thick with slotted holes.