Hello Guest it is July 07, 2020, 02:39:22 PM

Author Topic: New Machine Build - Mach 3 Help Needed!  (Read 5891 times)

0 Members and 1 Guest are viewing this topic.

Offline Dom

*
  •  22 22
    • View Profile
    • Bridgeport CNC Retrofit Blog
New Machine Build - Mach 3 Help Needed!
« on: June 15, 2009, 08:09:07 AM »
Hi all,

I'm just nearing completion of a bridgeport retrofit using mach 3, natrually I have read the manuals and watched the tutorial videos and I have got as far as cutting a few parts however there remains a few things which i'm unsure about so I'd be really greatful if someone could help me out.

First of all here is my current mach3 XML file: http://www.ukcnc.org/bpt.xml as I'm sure someone will ask for it at some point. I'm running Version R3.042.020

Now onto the questions:

#1 The other day I was using mach to mill some shapes from HDPE sheet. For one reason or another I chose to stop the cut cycle mid way by pressing the stop button. I then wanted to restart the program so I pressed rewind and then pressed goto zero so I could start again from the same place as before. However when I pressed goto zero it did not operate in the way I expected and all three axes moved at the same time (i.e before the z had time to rise above the material) and as a result it snapped my cutter.

#2 What I would like to know is if it is possible to change the operation of mach 3 so when pressing 'go to zero' it zeros the z axis before moving the x and y?

To reduce mechanical and electrical loads on my system, the acceleration ramps on my spindle inverter drive are set quite quite high - somewhere between 10 and 20 seconds. I have noticed that this causes problems when running g-code programs because Mach 3 starts cutting before my spindle has reached the set speed. How can I tell mach to delay for longer without individually modifying every g-code file ?

#3 Is it possible to get Mach to automatically return to it's G54 zero position at the end of a program without manually pressing goto zero?

#4 What do driver watchdog errors mean ? I seem to get a lot of these when running my spindle at full speed. Is it likley that noise from the VFD is causing these errors or is this just coincidence?

#5 Every time I load Mach3 I get a message saying "No Shuttle Detected of Type Selected" what does this mean and how can I get rid of it ?

#6 I have setup softlimits to protect both ends of each axis and on its own this works very well, making it impossible to jog into the limit switches or beyond accidently or otherwise. I thought it would be great to always have this feature enabled so I turned on softlimits and saved as default settings. Of course next time i loaded up mach 3 I get an error about softlimits exceeded  and I have to turn off softlimits so I can 'ref all home'. Also because I don't want my soft limits to be right on my real limits - I figured it would be sensible to allow some space for stuff to slow down etc , after homing I have to jog all my axes slightly off zero before I can turn soft limits back on.

My question is if it is possible to automate this process in some way, so softlimits are always on but are ignored until the axes are referenced upon each load and after referencing moves each axis just past zero so as not to retrigger the soft limit warning ?

#7 Since calibrating my axes to get a more precise steps per unit value, the DRO's no longer read what they are told. For example if I type in G0 X10, my X DRO displays +9.9996 I realise that this is only a very tiny difference but I do find it irritating that it's not displaying the number I asked it to display. Is there a way to solve this without compromising accuracy of the machine?

#8 How do most people go about transfering G-code files into mach 3? I'm wondering what is the common thing to do here. With my current setup I have a dedicated cnc controler pc which basically just has windows and mach 3 installed and nothing else. I then have a separate pc with all my cad/cam software and everything else. Originally I thought it would be nice and simple and easy to copy files from one to another with USB memory sticks, however experience has now shown me that this is actually really inconvenient espcially if you are prototyping something / experimenting and want to make lots of changes to a file and test out the results.

I'm thinking some sort of LAN/WLAN setup might be the nicest option so then I could save my CAM ouput from one computer directly into the mach3 gcode folder on the other computer. So is this what the rest of you do ? I'm just wondering firstly if the networking protocols are likley to interfere with the running of mach and also how to deal with the thread of viruses/worms. I've read that one should avoid running antivirus or firewall software on their mach pc as it can interfere with the pulsing but then without any of that its kind of exposed to any threats that try to spread accross the network.


I think thats about all for now. Sorry for writing an essay here but I guess that is partly new user syndrome - needing to know an awful lot about everything all at once! I will be very greatful to anyone who can help me out.

Regards,

Dom

Offline Hood

*
  •  25,846 25,846
  • Carnoustie, Scotland
    • View Profile
Re: New Machine Build - Mach 3 Help Needed!
« Reply #1 on: June 15, 2009, 08:50:44 AM »
Hi all,

I'm just nearing completion of a bridgeport retrofit using mach 3, natrually I have read the manuals and watched the tutorial videos and I have got as far as cutting a few parts however there remains a few things which i'm unsure about so I'd be really greatful if someone could help me out.

First of all here is my current mach3 XML file: http://www.ukcnc.org/bpt.xml as I'm sure someone will ask for it at some point. I'm running Version R3.042.020

Now onto the questions:

#1 The other day I was using mach to mill some shapes from HDPE sheet. For one reason or another I chose to stop the cut cycle mid way by pressing the stop button. I then wanted to restart the program so I pressed rewind and then pressed goto zero so I could start again from the same place as before. However when I pressed goto zero it did not operate in the way I expected and all three axes moved at the same time (i.e before the z had time to rise above the material) and as a result it snapped my cutter.

First thing is you shouldnt press Stop unless it is an emergency or the code is at a standstill. Reason is that it will stop instantly and you may lose position. The procedure if you want to halt is press FeedHold then once the axis has stopped you can then press Stop.
 Next thing is it sounds like you have not set a safe Z, if you had that set then the Z should  go up first, X and Y will then move then Z will again go down.
#2 What I would like to know is if it is possible to change the operation of mach 3 so when pressing 'go to zero' it zeros the z axis before moving the x and y?
Answered above
To reduce mechanical and electrical loads on my system, the acceleration ramps on my spindle inverter drive are set quite quite high - somewhere between 10 and 20 seconds. I have noticed that this causes problems when running g-code programs because Mach 3 starts cutting before my spindle has reached the set speed. How can I tell mach to delay for longer without individually modifying every g-code file ?
On Ports and Pins Spindle setup you can add a delay there for this purpose.
#3 Is it possible to get Mach to automatically return to it's G54 zero position at the end of a program without manually pressing goto zero?
Normal way would just to have the move in your G-Code but you could write a macro and then have an m code call that, the macro would basically press the GoToZero button. As you would have to write that m code to the end of the G Code then its probably just as easy to actually write the move in G Code

#4 What do driver watchdog errors mean ? I seem to get a lot of these when running my spindle at full speed. Is it likley that noise from the VFD is causing these errors or is this just coincidence?
Watchdogs can trigger for all sorts of reasons and Arts usual advice is disable them on the General Config page.
#5 Every time I load Mach3 I get a message saying "No Shuttle Detected of Type Selected" what does this mean and how can I get rid of it ?
Go to C:\Mach3\PlugIns and delete the shuttle plugin

#6 I have setup softlimits to protect both ends of each axis and on its own this works very well, making it impossible to jog into the limit switches or beyond accidently or otherwise. I thought it would be great to always have this feature enabled so I turned on softlimits and saved as default settings. Of course next time i loaded up mach 3 I get an error about softlimits exceeded  and I have to turn off softlimits so I can 'ref all home'. Also because I don't want my soft limits to be right on my real limits - I figured it would be sensible to allow some space for stuff to slow down etc , after homing I have to jog all my axes slightly off zero before I can turn soft limits back on.

My question is if it is possible to automate this process in some way, so softlimits are always on but are ignored until the axes are referenced upon each load and after referencing moves each axis just past zero so as not to retrigger the soft limit warning ?
You need to set the X and Y Min  and Z Max to zero on the Softlimits page, that way you can home fine with softlimits enabled. Just to make it clearer, the zero position once you have homed is when the axis has reversed and the switch has closed so going to zero in machine coords will not trip your limits. You will however need to set a slow zone so that if moving at full rapids  towards a softlimit Mach has time to decelerate, how big a slow zone you need will depend on your machione and will have to be found by trial and error.

#7 Since calibrating my axes to get a more precise steps per unit value, the DRO's no longer read what they are told. For example if I type in G0 X10, my X DRO displays +9.9996 I realise that this is only a very tiny difference but I do find it irritating that it's not displaying the number I asked it to display. Is there a way to solve this without compromising accuracy of the machine?
It is not a problem in reality as Mach keeps a check of where it is to many more decimal places. The reason however you see that is that because of your resolution (steps per unit) Mach is unable to move exactly to that position or the next step would take it past the commanded position.
#8 How do most people go about transfering G-code files into mach 3? I'm wondering what is the common thing to do here. With my current setup I have a dedicated cnc controler pc which basically just has windows and mach 3 installed and nothing else. I then have a separate pc with all my cad/cam software and everything else. Originally I thought it would be nice and simple and easy to copy files from one to another with USB memory sticks, however experience has now shown me that this is actually really inconvenient espcially if you are prototyping something / experimenting and want to make lots of changes to a file and test out the results.
I'm thinking some sort of LAN/WLAN setup might be the nicest option so then I could save my CAM ouput from one computer directly into the mach3 gcode folder on the other computer. So is this what the rest of you do ? I'm just wondering firstly if the networking protocols are likley to interfere with the running of mach and also how to deal with the thread of viruses/worms. I've read that one should avoid running antivirus or firewall software on their mach pc as it can interfere with the pulsing but then without any of that its kind of exposed to any threats that try to spread accross the network.


I think thats about all for now. Sorry for writing an essay here but I guess that is partly new user syndrome - needing to know an awful lot about everything all at once! I will be very greatful to anyone who can help me out.

Regards,
 Dom

I have my mill, lathe and desktop computer connected via network, I then place the code in a file on the machines computer and open from there. It is best not to load the code over the network so that is why I place it in a folder on the machines computer and load from there.

Hood


Offline Dom

*
  •  22 22
    • View Profile
    • Bridgeport CNC Retrofit Blog
Re: New Machine Build - Mach 3 Help Needed!
« Reply #2 on: June 15, 2009, 09:06:06 AM »
Cheers Hood, lots of things solved at once there. ;D

If I do as you suggest and set the min soft limits to 0 for x and y and 0 for max on z, wont that mean that I have no soft limits at all operating for one direction on each axis ?

Offline Hood

*
  •  25,846 25,846
  • Carnoustie, Scotland
    • View Profile
Re: New Machine Build - Mach 3 Help Needed!
« Reply #3 on: June 15, 2009, 09:09:24 AM »
The softlimits are in Machine Coords so setting the X and Y min will be at your machine coords zero position, ie exactly where your home switched closed again when you did your homing move. The X and Y Max and Z Min are set to your axis travels (Z being a negative number) so your softlimits are now set from Machine Zero to max travel of your axis :)
Hood

Offline Dom

*
  •  22 22
    • View Profile
    • Bridgeport CNC Retrofit Blog
Re: New Machine Build - Mach 3 Help Needed!
« Reply #4 on: June 15, 2009, 09:42:31 AM »
gotcha
Re: New Machine Build - Mach 3 Help Needed!
« Reply #5 on: March 27, 2012, 02:27:54 AM »
Hi, just to figure out another situation that occures.
i have G28.1 x0y0z0 init string when system loads, so It first ref all axis.
BUT, If i left the machine is a way, so one of the ref switches is ON, I get the message=
"Requested home axis home switch is active, please fix then home...."
and that axis can not be referenced.
How to skip that error, i mean doesn't matter that it is active, go REF anyway!?
 
thanks!