Bridgeport CNC

[amateur]

I am in the process of modernizing a bridgeport series one CNC
Does anyone know the torque output of the old stepper motors so I can cross reference them to newer efficient ones ?

Also any other hints,tips etc for those who have done this is appreciated.

[MaxHeadRoom]

Is that the older Slo-Syn's by Superior? I may have some numbers if you have model #.
One suggestion I have is to go servo.
Also check out the CNCzone for a few retro-fits done on these.
Max.

[John Stevenson]

They were advertised as 1100 oz/in but got loads here and none of them have a plate on bigger than 840 oz/in

Add to that the Bridgy drivers were the crappiest out at the time hence the big finned heat sinks on the motors.

I still have a beaver CNC mill with identical motors on it [ no heat sink ] running off the Chinese 80volt 7.8 amp drive wired in parallel.
Has been running flawlessly for ages.

On a machine this size servo's are really the way to go if you can afford it.
When I converted mine step and direction servo drives was dead rare but times have moved on.

[amateur]

Thanks for the replies.
Are the drivers different for servos vs steppers ?Has anyone done a cost comparison for both ?

[macona]

New drive, motors, and power supplies for steppers, 800 to 1000. This assumes new and they are pretty big motors.

Probably about 505 more for servos but the performance is so much better. I have brushless servos on my mill now and they are wonderful.

I have steered a couple people in putting servos in place of the old steppers. McGyver has a thread on his conversion:

http://bbs.homeshopmachinist.net/showthread.php?t=42954

[amateur]

1500 doesn't sound too bad.I just don't want to purchase drivers ,motors etc to find out their unsuitable for this conversion.

[macona]

This seller often has packages of matched drives and motors for sale, you might send them a message about getting a set of three motors. I would say 750 watt motors for the x and y and if it is a quill for Z I would use a 400w there. I have Mitsubishi 1kw motors and drives on my mill and it is pretty overkill.

http://www.ebay.com/sch/fa-parts/m.h...id=p4340.l2562

[macona]

He has yaskawa 750 watts for $550 a piece.

http://www.ebay.com/itm/YASKAWA-SGDL...ht_2341wt_1110

[MaxHeadRoom]

Check out http://www.dmm-tech.com/Products.html
Also they are in Canada.
Max.

[amateur]

The "servo pack" is that like a motor plus driver ?