Hello Guest it is March 28, 2024, 10:38:18 AM

Author Topic: Home Offset Proble  (Read 3976 times)

0 Members and 1 Guest are viewing this topic.

Home Offset Proble
« on: May 22, 2013, 01:48:03 PM »
I have spent days searching the forum for information on a problem I am experiencing.  I have not been able to find an answer.

I use a plate and clip on the end mill for the Z axis home.  After setting up the homing an home offset it works fine for a while.  If Mach3 terminates abnormally (power failure etc.), the ref all home function et the Z axis to a different value from that on the homing/limits screen.  It is acting like there is a value stored somewhere else that is added to the value on the homing/limits screen.

Replacing the XML config file and redoing the Z axis home does not help.  So far the only way to get it working correctly again is to uninstall Mach3. Delete the C:\Mach3 folder, install Mach3 and redo the Z axis home setup. 

This is getting to be very frustrating to me.

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: Home Offset Proble
« Reply #1 on: May 22, 2013, 02:40:39 PM »
Do you have home switches set up on your machine?

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!
Re: Home Offset Proble
« Reply #2 on: May 22, 2013, 05:49:12 PM »
I do not use home switches.  I use an aluminum plate on top of the material as 1/2 of the Z axis home circuit.  The other half is a wire with an aligator clip for cliping on the bit.

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: Home Offset Proble
« Reply #3 on: May 22, 2013, 06:33:06 PM »
OK, all offsets are based on machine coordinates which is what you set when you reference the machine.  When you fire Mach up do you jog to a known location and hit the reference all button?  Setting your work coordinates 0 and your reference (machine) zero are 2 totaly different things.

Brett

;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!
Re: Home Offset Proble
« Reply #4 on: May 22, 2013, 07:32:04 PM »
OK, all offsets are based on machine coordinates which is what you set when you reference the machine.  When you fire Mach up do you jog to a known location and hit the reference all button?  Setting your work coordinates 0 and your reference (machine) zero are 2 totaly different things.

Brett


OK, all offsets are based on machine coordinates which is what you set when you reference the machine.  When you fire Mach up do you jog to a known location and hit the reference all button?  Setting your work coordinates 0 and your reference (machine) zero are 2 totaly different things.

Brett



I don't mean to sound dense but I am now confused.  I do the following and, until the problem starts, it usually gives the desired results:
1.  Turn on the computer and drive electronics.
2.  Turn the machine on.
3.  Load Mach3.
4.  Click Reset.
5.  Mount the material in the desired location.
6.  Jog the tool to where I want X0 and Y0.
7.  Set the homing plate on the op of the material and clip to other circuit wire to the bit.
8.  Click Ref All Home.

At this point the Z axis will descend until it touches the plate then back off slightly.
It is supposed to set the Z axis to the value in Home Offset for Z Home (+0.2300).
I then set X and Y to 0.

Currently it is setting the Z axis to some value like +2.3950 even though Z Home Offset is set to +0.2300.

I am unsure as to what a "known Location" is.  I assume machine 0 is the position of the tool when the machine is at the limit of travel in the negative direction for each axis.

It appears that the program is using the values from the last known position before the crash as a base number and adding the value in home offset to it.  Jogging to a position does not affect this behavior.

Glenn
 

Offline Chaoticone

*
  • *
  •  5,624 5,624
  • Precision Chaos
    • View Profile
Re: Home Offset Proble
« Reply #5 on: May 22, 2013, 08:09:37 PM »
The way your using your plate as a z home switch should work.  When you do this and the number is some number other than the +0.230 you have set for your home off distance, are you looking at the machine coord. DRO or the work Coord. Dros.  I'm assuming work Coords becasue when you do a ref all home the machine coord. dros of x and y should zero out by them selves if you do not have home switches enabled in ports and pins for the x and/or y axis.  When you say

Quote
I then set X and Y to 0.

I think you are zeroing your work coord. DROS by clicking the zero x and zero y buttons beside their respective dros.  This will not zero the machine coor. dros although they should be because you just referenced the machine (if you haven't moved it).  Run through your routine and before you jog press the MAchine Coord. button below the dros and see if the z number is what you set for your z home off distance.

Brett
;D If you could see the things I have in my head, you would be laughing too. ;D

My guard dog is not what you need to worry about!
Re: Home Offset Proble
« Reply #6 on: May 24, 2013, 05:54:51 PM »
ready to finish the renovation of my air compressor, Craftman. Got a single phase input to 3ph output VFD for 152$... So far Im way under buying just a nice branded electric motor.. A single ph 1.5 from baldors or leesons is approx 400dollars. Have looked at Baldors, and found one that is more or less compatible  https://www.mrosupply.com/ what do you think of this Baldor brand? or is Leeson better?
Thanks!