Milling machine upgrade

[johnno402002]

Hi,

I'm upgrading my milling machine from steppers to servo motors. I'm being offered a choice between incremental encoders and absolute encoders on the servos. I have the basic idea of one vs the other, but not in the context of using them with the Masso. I have limit switches on both ends of the x and y axis, and only on the upper limit of the z axis, not quite sure why the lower limit is not there, I'm guessing because with different tool lengths in the spindle it's not all that relevant, and the table is a full stop.

Anyone have an opinion on which I should use with the Masso, incremental or absolute encoders?

2nd question, I have the option of a brake on the z axis motor, it seems like a good idea when machining flat surfaces to stop any slight quivering of the z axis while the servo tries to hold it still. Can the Masso handle applying the brake when the z axis is not moving?

John

 

[solargrown]

I'm certainly no expert.........

I found clearpath SDSK servos from Teknic to be very easy to setup & tune

Once you setup soft limits in MASSO you can get away with one limit switch on each axis

A brake on my Z axis is on my list of things to look into, only reason being once the servo loses power (i.e E-stop) spindle starts to drop. Whilst powered I can just hear the clearpath maintaining Z position, no movement though.

My 2 bobs worth.......

Peter

 

[johnno402002]

Thanks for the feedback Peter, much appreciated.

I have looked at the clearpath servos, I liked them. I 3d printed one to see if I could fit it into the machine, but no luck on the z axis, it's mounted in the bottom of the column and the clearpath is too short and round to squeeze in there, and its connections protruding off the side rule it out. The others I'm looking at are more like a greyhound, long and skinny, and the machine manufacturer is supplying them with the tuning already set. They had never heard of a Masso, hence the questions.

John

 

[masso-support]

@johnno402002 for the incremental encoders and absolute encoders question, it won't make any difference as you will still need to use homing inputs to home each axis. Rest the tool lengths etc are all manged by MASSO.

For the brake part, the brake is actually controlled by the motor drive itself and is mainly used in case the power fails and the z axis might try to drop down, so the brake is applied by the motor drive itself when power is lost.

 

[johnno402002]

Thanks for the feedback, much appreciated.

John