Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: nanoplane on December 07, 2010, 12:09:06 PM

Title: Suddenly Goto Zero isn't working right...
Post by: nanoplane on December 07, 2010, 12:09:06 PM
I'm a relatively new Mach3 user (a month or two).  Things have been great! except...

A few days ago, goto zero stopped working correctly.  it drives the Y and Z axis correctly to the zero, but the X axis stepper just "buzzes" and doesn't move.  During actual milling operations all works fine, it's just the go to zero that fails.

Andy ideas??

--marcel
Title: Re: Suddenly Goto Zero isn't working right...
Post by: Hood on December 07, 2010, 02:11:06 PM
Your motor is stalling, what is causing it could be one of many problems, a few of which could be
Axis is binding
Power supply is failing
Loose connections
Drive or motor failing


You can maybe try swapping drives and motors around to see if you can make the problem follow the component but just do one at a time.

Hood
Title: Re: Suddenly Goto Zero isn't working right...
Post by: nanoplane on December 07, 2010, 03:43:46 PM
I don't think that is the issue,  Like I said, it works fine during any milling operation or manual jog or in the "test" screens. 

The only thing that doesn't work is when I hit the "goto zero" button.

Everything else works fine..
Title: Re: Suddenly Goto Zero isn't working right...
Post by: Hood on December 07, 2010, 03:54:29 PM
Please attach your xml.
Hood
Title: Re: Suddenly Goto Zero isn't working right...
Post by: nanoplane on December 07, 2010, 10:55:14 PM
Hmm Ok, something weird happened... I attached the file and hit the post button... but my message didn't appear to get posted.  When I tried a second time, it says my attached file already exists..

Forum seems to be acting flakey for me today...
Title: Re: Suddenly Goto Zero isn't working right...
Post by: nanoplane on December 08, 2010, 12:10:00 AM
Trying again.. changing the file name to protect the guilty..
Title: Re: Suddenly Goto Zero isn't working right...
Post by: Hood on December 08, 2010, 04:11:38 AM
XML looks fine, what happens if you command a rapid move for both X and Y from the MDI line, eg G0X100Y100

Hood
Title: Re: Suddenly Goto Zero isn't working right...
Post by: nanoplane on December 08, 2010, 08:45:26 AM
ok, so that's interesting...

G0X4Y4 (it's a small mill).. The X moves 4", the Y stalls about 1/2 way
G0X4 the x stalls about 1/2 way
G0Y4 the y stalls about 1/2 way

G0X4Y4 (second try) Both axis stalled about 1/2 way.

sometimes I'm lucky and it will succeed, other times I'm not..
I'm beginning to suspect hardware... the computer is rather old..

Title: Re: Suddenly Goto Zero isn't working right...
Post by: Hood on December 08, 2010, 08:54:39 AM
I dont think its computer, much more likely either accel/Vel settings too high or that you have binding axis or maybe power supply is varying too much. If you have a volt meter check on the DC side of the power supply and see if it varies quite a bit when you command a rapid move.

Hood
Title: Re: Suddenly Goto Zero isn't working right...
Post by: jtcdudeman on December 08, 2010, 10:01:02 PM
I agree with Hood.   Im a complete newbie though, so it may not be worth much.

Try going into the config drop down.  Then, clicking on motor tuning.   

Then, cut your acceleration in half of what you have listed on each axis  and drop the velocity down to about 2/3 of what its set at now.  Leave the steps alone.

Then, try repeating the problematic action.   If it cures it, your motor settings were too optimistic.   I've read you should set your motors at about 80% of what they are listed.  Ive slowed mine down to about 20% of max because everything is moving faster than I can handle right now (my confidence anyways.)
Title: Re: Suddenly Goto Zero isn't working right...
Post by: nanoplane on December 09, 2010, 12:28:00 AM
And you were all right... my max speed was set to about 27 in / minute and with microstepping to 16000 pulses per inch... it was just too dang fast... but only since the weather got colder... :-)  When I bought the mill in the summer time it worked fine

It's all working now though,  thanks to you all

--marcel