Method to prevent Z falling down

Hello,

I am retrofitting a machining center where the Z axis have a brake to prevent the axis from falling down. The problem is when power fails (or any other error) related with axis drive, the axis falls down about 0.5-1mm before the brake fully stops the axis.

This will result in broken tools and broken jobs if happens during work.

What do you guys use/what method can solve this so that the tools are safe? I am using the original machine drives, where a signal "drive ok" is monitorized by linuxcnc that opens or close the brake.

Any ideia is welcome.

Thank you

emcPT wrote: I am retrofitting a machining center where the Z axis have a brake to prevent the axis from falling down. The problem is when power fails (or any other error) related with axis drive, the axis falls down about 0.5-1mm before the brake fully stops the axis.

I don't think that there is a solution with the existing hardware. Is there any possibility of fitting a counterbalance piston?

Fitting any counterbalance system is out of consideration due to space and complexity.
I wonder if this is a "normal" problem in VMC. I had only 2, industrial grade, on my hands before. One had the same problem (with a Fanuc controller) and the other did not lowered (Hurco VMC), and it did not had any counterbalance.

It sounds like the brake would have to predict the power failure or drive drop-out, and that seems to be a fundamental difficulty.