Scaling problem need help

[rcico2001]

Hello Everyone, I am new here and need some help, I have the mach 3 (maxNC) and I have a problem with the size. I load a regular g code that works fine on an accurite mill pwer and it worked fine on my friends max nc with mach 3 and comes out to size. Here is the problem when I use it on my machine (max NC OL10) that the engaving comes out 8 times smaller. The program has been installesd and reinstalled and no change. I am a new user to this and I dont want to go and change other field s etc. I have measured with a ruler 1" movement on xyz and they come in at over 8.134 on the dro. I hope someone ccan help me here I would really appreciate it.

Thank you

best
Romano

[Hood]

Sounds like your steps per unit sound  are wrong.
Hood

[rcico2001]

Hello Hood, I am a real beginer at this. Can you tell me how to take care of this  with the steps
best
romano

[Hood]

In Motor tuning you need to set a Steps per unit for each axis you are using. This is a calculated value and will depend on the hardware you have.
As an example a machine may have 1.8 degree steppers(200 steps per rev) and use 10 micro step drives, the motor is coupled direct to the ballscrew which is 0.2 pitch.
With these figures you can work out the steps per unit, it would take 200 steps to rotate the motor one turn but because there is microstepping it would then be 200 x 10usteps = 2000 to rotate 1 turn. One turn of the motor would turn the ballscrew one turn and because it is 0.2" pitch it would take 5 turns to move one inch or one unit. So 2000 x 5 would equal 10,000steps per unit.

So if you know the components you can work out what the steps per unit should be.

Hood

[alenz]

Hood, I wonder if this little spreadsheet might help folks setting up their machine for the first time?
If so where would be a good place to post it?
Thanks,
Al

[Hood]

Looks good
Members docs will likely be the place for it.

Hood

[rcico2001]

hello Alenz thank you for the info. Where would i go in mach III to set up these motors ? in the setting tab ? Any info how to put the info into the correct slot would be great. I just dont want to mess anything up.
Thanks for your help
best
Romano

[RICH]

Alenz,

I created a thread and posted the spread sheet in Members Doc's for you.
Here is the link:

http://www.machsupport.com/forum/index.php/topic,16315.0.html

Thanks for your efforts,

RICH

[alenz]

Romano,
From Mach3’s main menu select ‘Config’, then ‘Motor Tuning’. A ‘Motor Tuning and Setup’ window will open. Select the axis that you want to set, then enter the ‘Steps Per’ value in the lower left box. Then hit ‘Save Axis Settings’ and OK. That should do it.
Rich thanks.
al

[rcico2001]

Thank you Al. right now the Step box says 4000 in the steps and then in the velocity its is 49.998 and the next box step pulse is 0 and the Dir pulse is 0

if I start lowering the number lets say 2000 in the box this will start lowering. Like I mentioned in the older post that I measured 1" on x and the DRO said 8.12. will I have to alter any of the other boxes ?

Am I on the right track here altering that number in the step box ?

thanks for your help
best
Romano