CNC Spindle Counterbalance using Constant Force Springs

With both my previous Onefinity Z20 Z axis, and current custom Z axis assembly, my heavy ATC spindle would slowly drift down on system power down. I remedied this with a high torque stepper with brake, but because my ATC spindle/Z assembly is very heavy, I had always wanted to relieve the added forces experienced by some of the linear motion components. After researching several options, I decided to use constant force springs as they were the simplest, lightest, most compact, and cost effective solution compared to the other choices. This video shares some of the design, installation, and machining related to this solution.