slow-poke
Ultra Member
I have pretty much completed the X and Y axis ballscrew and servo upgrade for my knee mill. I'm directly driving the ballscrew with the servo. On my old RC mill I used gear reduction with belts and pulleys, the new system is simple and I like simplicity. The ac servos I'm using for the new mill have a REALY flat torque curve and MUCH higher peak torque compared to the steppers used for the RC mill.
I'm now thinking about the knee. I have seen some CNC conversions where they use some form of gear reduction and I would prefer to keep it simple and directly drive the knee handcrank shaft. Will likely have to add some gas charged struts to counter the weight of the knee. Has anyone done this and if so what sized servo ( continuous and peak)?
The graph below is for the X&Y axis servos, they have larger servos (1kW) if necessary I have drilled the mounting plate for the servo drives to accommodate either drive.
I'm now thinking about the knee. I have seen some CNC conversions where they use some form of gear reduction and I would prefer to keep it simple and directly drive the knee handcrank shaft. Will likely have to add some gas charged struts to counter the weight of the knee. Has anyone done this and if so what sized servo ( continuous and peak)?
The graph below is for the X&Y axis servos, they have larger servos (1kW) if necessary I have drilled the mounting plate for the servo drives to accommodate either drive.
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