Messages

1

Mach3 and G-Rex / Re: Newbie help Please!!!!!!

« on: February 04, 2010, 03:48:22 AM »

Please Any Suggestions!!!!!!

2

Mach3 and G-Rex / Newbie help Please!!!!!!

« on: February 02, 2010, 04:40:25 AM »

Hi all,

I've built a 3 axis CNC table and it works fine but i was wondering if it was possible to have the home position in a different place.

At the moment when i press ref home the motors move to the bottom left hand corner, just like what is shown on Mach3.

What i would like to do is have the home position at the top left hand corner. The reason for this is if the table is at the home position at he moment it is very difficult to place anything on the table as the drill covers the working area.

What would be ideal is for the table to go home first on pressing the ref home and the for the y axis to move to postion y250 x0 then i would be able to get at the surface area.

I hope someone will be able to help me.

Regards

Rick

3

General Mach Discussion / Re: Scaling Problem - Help Needed

« on: October 14, 2009, 10:50:51 AM »

Yes it was set at 800 initailly but now that i have run the Automatic calculation setup this value has now reduce to 81 which is closer to your calcuation

Rick

4

General Mach Discussion / Re: Scaling Problem - Help Needed

« on: October 14, 2009, 10:12:37 AM »

Hood

Thx for working out the steps per mm.

Quick question. I've tried using the Automatic Setting of Steps per Unit and is almost sync in the X, Y and Z axis.

Would using your calculation be more accurate than using the Automatic setting built into Mach3?

If it's better to use the Automatic settings is it better to measure over a longer or shorter distance?

The reason i ask regarding the distance to measure is because at the moment after using the Automatic settings over a short distance the movement is perfect but as the distance increases the accuracy reduces, this can be up to 1mm over a distance of 100mm.

Thanks for your help in advance

Rick

5

General Mach Discussion / Re: Scaling Problem - Help Needed

« on: October 13, 2009, 12:09:45 PM »

Hi

I've been reading the manual and i've now set the steps to 1/16 and i'm using for the time being 800 steps per unit. this figure seems to be as close as i'm going to get it until i can work out the proper equation!!

regards

Rick
 

6

General Mach Discussion / Re: Scaling Problem - Help Needed

« on: October 13, 2009, 09:27:58 AM »

It sounds like your steps per unit is incorrect. What pitch is your leadscrew? how many steps on your steppers? and what microstep did you select? These are what will affect the differences in travel from what I understand.

Thanks for the quick reply

The stepper motors are 1.8 degrees full step but i'm running them at 1/2 step.

I'm not using a lead screw on the X and Y drivers. My milling machine has a toothed wheel and belt system, each belt pitch is 2.03mm and the toothed wheel outer diameter is 12.93mm and the pitch is 2.03mm with 20 teeth.

The size of my working table area is 435mm x 275mm

see here for more info :
Pully - http://www.mcmaster.com/#1375K39
Belt - http://www.mcmaster.com/#7959K21

Kind regards

Rick

7

General Mach Discussion / Scaling Problem - Help Needed

« on: October 13, 2009, 08:37:10 AM »

Hi all

I need help with scaling :

I have set up my milling machine using Mach 3 software but i've come across a scaling problem between the X and Y coordinates on the screen and the X and Y coordinates on my milling table.

For example : a movement of 200mm on the table relates to 0.9mm on the DRO's

How do i set the correct scale on both X and Y axis so that 100mm on the DRO's equal 100mm on the table.

I've comfigured the software in mm's and i've set the milling table size in the Homing/Limits page.

Kind Regards

Rick