Z axis moving too much

My apologies if this has been covered somewhere but I didn’t find it.

I noticed that my z axis moves up and down too much. I first noticed it when I set easel to move the axis down 1" and found it moved much more. I took a quick measure and saw that it moved about 1 3/4 ". Does anyone know what may be wrong? I have checked the settings under “machine” and made sure it was an X-Carve, 1000mm machine, ACME lead screw and dewalt 611 spindle.

Thanks.

Have you calibrate the stepper motors (steps per mm)? This should be the last step in the the “Calibrate” during set up of the X-Carve, but it’s not listed and I also forgot about it.

Robert from Manhattan Wood Project has a great video on how to do it, https://www.youtube.com/watch?v=vSxFutlfngk

Also Triquetra-CNC has a Stepper Calibration Spreadsheet so you don’t have to do the math, http://triquetra-cnc.com/stepper-calibration-spreadsheet-sign/

or search Google or YouTube or here on “Stepper Calibration” for more info

Also this may not be your only problem, the default settings are normally very close. Like I was only off by .07in / 1.778mm

In easel, go to machine, advanced, machine inspector and look into the value, 1 3/4 is too much for just a calibration, your settings must be off somewhere
$102= number of steps (z, step/mm), what is your setting?
How much is the pitch of the ACME rod?
Are ou using a direct drive or two pulleys, are both pulleys the same diameter? If not what do you use on the motor and rod.

There is nothing wrong with a little math!

Thanks Doug and Erik.

It seems I must have been sniffing too much saw dust (or router dust after a long day). I went out and bought a dial indicator and redid my measurements and they are pretty close to being bang on. I am going to try and do the calibrations Doug mentioned this weekend since I didn’t even know to do that.

Erik, if it still matters, here are the settings from my machine.

Genttlemen, thank you for your very quick responses. I bought my machine late last year but with coaching youth baseball this year I have only really started to use it in the last month or so and I am trying to learn more about what it, and I, can do.