Hello Guest it is April 18, 2024, 03:28:29 PM

Author Topic: very strange problem  (Read 6269 times)

0 Members and 1 Guest are viewing this topic.

very strange problem
« on: August 11, 2009, 03:33:46 AM »
hi all i am marco from the netherlands and i am trying to build a cnc portal machine

i am so far that i can move 2 axes with mach3  with th arrow's only thing is

i can move the both in 1 dirrection as soon as i change 1 direction off a axes it stops or makes a lot off noise and move strange

and another thing is

if i move the x as it works great but if i want the move the y as it works only one way i have to give the x as another hit and then the y as works in both ways

hardware

p4 q6600

breakoutboard http://cgi.ebay.nl/CNC-DB25-Breakout-Board_W0QQitemZ120436845158QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item1c0a986a66&_trksid=p3286.m63.l1177

2 microdrivers leadshine M542

power supply 48v 8 amp

i made a small video off it
http://www.youtube.com/watch?v=YCppWxqDgFk

if someone has a idea what i can try

thnx in advange

« Last Edit: August 11, 2009, 03:37:26 AM by marcoooo »

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: very strange problem
« Reply #1 on: August 11, 2009, 04:49:31 AM »
please attach your xml.
Hood
Re: very strange problem
« Reply #2 on: August 11, 2009, 05:03:35 AM »
thnx for your time

i attached a zip file

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: very strange problem
« Reply #3 on: August 11, 2009, 05:15:41 AM »
Have you got the steps per Inch set correctly? you seem to just have the standard settings for that in the motor tuning and all axis are the same. This may be correct but as your motors sound like they are stalling I am guessing that is your issue.
Hood
Re: very strange problem
« Reply #4 on: August 11, 2009, 05:27:29 AM »
it should be m/m

and all axes are the same motors and spindels

but the strange thing is how is it possible it works in one way 2 axes the same time bbut when i switch to the other side with one axes it goes wrong

sorry for the noob question what can i do if the motor is stalling ?



Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: very strange problem
« Reply #5 on: August 11, 2009, 05:35:34 AM »
If the xml you sent me is the one you are using then you have the native units set to inches.
 What is the pitch of your ballscrews?
 What microstepping do you have the drives set to?
 What is the gearing between motor and screw?
If indeed your steps per mm are 2000 then your kernel speed will need to be increased when you change the native units to mm rather than inches as with your present setting of 25KHz your max rapid would be 750mm/min

Hood
Re: very strange problem
« Reply #6 on: August 11, 2009, 06:06:27 AM »
the nut move's 5 m/m a turn

microstep = at the moment  800 steps a turn

so that will bring me to

800/5=160 steps a m/m

the steppers to the spindel = 1:1

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: very strange problem
« Reply #7 on: August 11, 2009, 06:12:42 AM »
Ok the xml you sent me has Inch as default units and is set to 2000 steps per unit, check and see if this is what you are seeing, if not then you have sent the wrong xml. If it is then you need to set the correct default units and  steps per unit and then retune your motors. You would likely be better setting to 8 or 10 microstepping which would equate to 1600 or 2000 on the drives dip switches.
Hood
« Last Edit: August 11, 2009, 06:16:08 AM by Hood »
Re: very strange problem
« Reply #8 on: August 11, 2009, 08:51:44 AM »
did some playing with mach3

and if i disable a axes in port en pins the other axes just does what it should do  visa versa the problems begins when i enable both axes
is it possible mine 5 v psu for the breakoutboard is to weak to controlle 2 drivers
i used a old nokia adaptor for it  it is 5v 800 mA ?

thats all i can think off at the moment

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: very strange problem
« Reply #9 on: August 11, 2009, 09:02:43 AM »
Are you using the xml you attached or is it a different one? If you are then that will cause problems in as much as accuracy is concerned and that should be your first step to resolve any issues.

As for the 5v, that should be fine as the requirements of the power supply should just be milli amps,  however I should qualify that by saying I am not familiar with the CNC4PC boards and their requirements.  It is more likely to be your motors power supply that is an issue if you are not able to move two or more axis at one time but all are fine when moved individually. Put a voltmeter on the drives power input terminals and jog one axis and see what it reads, then jog two axis and see if the voltage drops.
 Another thing that could be causing issues is if your Step/Dir cables are not shielded and properly grounded at one single point. This could cause noise to be introduced when you are moving multiple axis.
Hood