[Chmfhm]

I am planning to make diy fixed gantry mill


Working area 1000mmx600mm

Also i am considering bt30atc 12000rpm spindle as in pictures.

I need an idea of counterweight system for z axis


Does anyone have any ideas. or related image or video

[awerby]

I used gas springs to counterweight a heavy spindle. They worked much better than the constant-force springs I tried first (which broke) and were easier to implement than an actual counterweight, which needs to accommodate the sideways motion of the axis as it moves in Y.

[mactec54]

I am planning to make diy fixed gantry mill


Working area 1000mmx600mm

Also i am considering bt30atc 12000rpm spindle as in pictures.

I need an idea of counterweight system for z axis


Does anyone have any ideas. or related image or video

If you build it correct you won't need a counterweight most would use an air cylinder for a machine this size if it needed it, normally all you need if your Servo motor is sized correct is a Brake which on most machining centers is built into the Servo motor, some are on the Z axis Ballscrew, mostly though are on the Servo Motor with using an air cylinder it is just a closed loop system with an air reservoir

[joeavaerage]

Hi,
if your Z axis servo/ballscrew combination either cannot or struggles to pick up its own axis weight and spindle WITHOUT the assistance of counterweight or
similar how the hell do you expect it to deal with cutting forces and Up/Down acceleration?. The Z axis should have easily tens times the thrust of its own weight.

Craig

[awerby]

Often the problem isn't in driving the axis up and down, but having the axis fall to the table when power to it is turned off. A brake, like Mactec refers to, can also stop that from happening, but it can be hard to implement if the motor doesn't come equipped with one.

[joeavaerage]

Hi,
I used 750W Delta B2 servos on my new mill. The unbraked ones were $438USD per kit (servo, drive and cables) and the one braked one I got for the Z axis cost $541USD.
The extra $102USD for the brake is a no brainer.

Craig

[mactec54]

Often the problem isn't in driving the axis up and down, but having the axis fall to the table when power to it is turned off. A brake, like Mactec refers to, can also stop that from happening, but it can be hard to implement if the motor doesn't come equipped with one.

All servo motor manufacturers offer their motors with or without a Brake, it's as simple as buying the right motor for your application

[Chmfhm]

Thx everyone i will go for servo motors with brakes

[mactec54]

Thx everyone i will go for servo motors with brakes

You only need a servo motor with a Brake for the Z axis only