Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: kilroyjones on March 24, 2007, 06:21:47 PM

Title: Noob with motor/encoder problems.
Post by: kilroyjones on March 24, 2007, 06:21:47 PM
I just got into hobby CNC and found I am way over my head. I run CNC machines at work, but they are already configured.

When I try to configure Mach3 in motor tuning, I end up with a DRO display that doesn't match the actual movement of the table. I am using a dial indicator to measure the actual table movement.

I checked the leadscrews on the Sherline with a thread guage and it is 20 TPI.
Divide 1 by 20 and I get 0.05" screw pitch. Which gives me 20 revs/inch.

The steppers are labeled as 1.8 degrees/step so I have 200 steps/rev. 200x20 gives me 4000 steps per inch(?)

In the Motor Tuning screen I set the STEPS PER @ 40000   VEL @ 12.75    ACEL @ 0.5625

I checked and Mach3 is set to "inch". So what simple thing is there that I am overlooking?
Title: Re: Noob with motor/encoder problems.
Post by: Hood on March 24, 2007, 06:44:15 PM
What drives do you have? are they Full stepping,  Half stepping , micro stepping or .......
You will need to multiply your steps per inch by the stepping of your drives.
 Also if you have any reduction between the motor and the screw you will have to take that into account.
Hood
Title: Re: Noob with motor/encoder problems.
Post by: kilroyjones on March 24, 2007, 07:33:03 PM
The drives are PowerMax II running off of a MaxNc10 controller. Thanks for the help, I will search the web and see what type of drive the PowerMax is....
Title: Re: Noob with motor/encoder problems.
Post by: Hood on March 24, 2007, 07:36:57 PM
Have you tried the auto setup on the settings page, its just above the reset button. This will allow you to enter a distance to move, you then measure that actual distance moved and Mach will set your steps correctly.
Hood
Title: Re: Noob with motor/encoder problems.
Post by: kilroyjones on March 24, 2007, 07:44:59 PM
Hood,

 Thanks! I knew it had to be something simple...

I used the auto set-up an it gave me 10,0000 steps per. I jogged the table .010" and got a perfect .010" reading on my indicator. Thanks again!
Title: Re: Noob with motor/encoder problems.
Post by: Hood on March 24, 2007, 07:48:29 PM
Glad you got it going, have fun :)