Go Back   AzBilliards.com > Products Talk > Ask The Cuemaker
Reload this Page Speaking of Mach 3 offsets and limits
Reply
Page 2 of 3 12 3
 
Share Thread Tools Rate Thread
Old
  (#16)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-22-2020, 09:39 AM

I made a video on how to home a cnc without home switches, and how to use that in conjunction with the work offsets, safe Z, Z28 home, and more. This was very confusing to me when I started in cnc world, and probably confusing to most of us when we started. I hope it helps!

Link:
https://youtu.be/Wg8I5eFKgz0
  
Reply With Quote

Old
  (#17)
whammo57
Kim Walker
whammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond reputewhammo57 has a reputation beyond repute
 
whammo57's Avatar
 
Status: Offline
Posts: 4,211
vCash: 500
iTrader: 2 / 100%
Join Date: Dec 2009
Location: Near Athens GA
   
05-22-2020, 06:15 PM

I have been trying to follow this thread but....... I am missing something/....

when I draw a part or inlay... it is drawn in BobCad on a coordinate system........ I know where zero is........... on the part or the material.............

when I run it ... I set my zero at that position ....... and press cycle start

Kim


Walker Custom Cues

Southern Cue Systems

http://www.facebook.com/groups/366326706736784/
  
Reply With Quote
Old
  (#18)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-22-2020, 06:35 PM

<=== Not a cue maker....


What if you have a cnc router with a big table. And you set up 4 identical stations with rotating axes on it, so you can inlay 4 cues while you do something else in the shop. Each of those cues would be on its own work offset.

Or, you have 4 different stations on that table. One for turning shafts, one for pocketing inlays, one for cutting out inlays from a sheet, and one for cutting grooves for trim rings. Each station would have its own offset. So if you select a new zero for the station for cutting inlays from a sheet, it won't affect your zero for the station that turns shafts.

You need a home position, and offsets for each station, to do that. Otherwise, you'd be using the same offset for each station, and would have to ruin your 0,0 anytime you change stations.
  
Reply With Quote
Old
  (#19)
JC
The Thread Stops Here
JC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond repute
 
Status: Offline
Posts: 12,613
vCash: 500
iTrader: 28 / 100%
Join Date: Oct 2011
Location: PNW
   
05-22-2020, 07:38 PM

Quote:
Originally Posted by whammo57 View Post
I have been trying to follow this thread but....... I am missing something/....

when I draw a part or inlay... it is drawn in BobCad on a coordinate system........ I know where zero is........... on the part or the material.............

when I run it ... I set my zero at that position ....... and press cycle start

Kim
The reason I want a repeatable zero in an offset is to be able to go back to the exact center of round stock mounted between centers on the fourth axis. Really it's only the X axis I care much about. Jogging to exact center ends up taking more time than I want to use over and over again each time after I do something else on the table and zero there. I want to establish the center line of my dovetail and keep it.

That's my motive anyway. Lots of ways to skin a cat I like to do it fast.
  
Reply With Quote
Old
  (#20)
conetip
AzB Silver Member
conetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond reputeconetip has a reputation beyond repute
 
conetip's Avatar
 
Status: Offline
Posts: 5,312
vCash: 2900
iTrader: 28 / 100%
Join Date: Nov 2007
Location: Hamilton, New Zealand
   
05-24-2020, 01:11 AM

Quote:
Originally Posted by iusedtoberich View Post
I made a video on how to home a cnc without home switches, and how to use that in conjunction with the work offsets, safe Z, Z28 home, and more. This was very confusing to me when I started in cnc world, and probably confusing to most of us when we started. I hope it helps!

Link:
https://youtu.be/Wg8I5eFKgz0
Thank you for the informative video. I will bookmark this for future reference.

Neil


Neil Lickfold.
Cuttlefish Cues.
cuttlefishcues@gmail.com
Sorry, not taking any cue orders until further notice.
  
Reply With Quote
Old
  (#21)
JC
The Thread Stops Here
JC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond repute
 
Status: Offline
Posts: 12,613
vCash: 500
iTrader: 28 / 100%
Join Date: Oct 2011
Location: PNW
   
05-24-2020, 09:10 AM

Quote:
Originally Posted by iusedtoberich View Post
I made a video on how to home a cnc without home switches, and how to use that in conjunction with the work offsets, safe Z, Z28 home, and more. This was very confusing to me when I started in cnc world, and probably confusing to most of us when we started. I hope it helps!

Link:
https://youtu.be/Wg8I5eFKgz0
Very nice video thank you. I am really starting to grasp the whole home and offset strategy.

Where did you get the GUI? It looks nothing like the mach3 screens I'm used to.

Also I'm a little confused about the reason for setting machine coordinates in g53. If you sync G54 with the machine coordinates and soft limits aren't you accomplishing the same thing? Without having to ever type any commands? G54 then becomes a mirror of g53 and is the defacto home, you just burn the offset for other uses but there's plenty more to use.

Also my experience is that unless you have a power failure not allowing you to exit mach normally or move your machine manually after shut down that Mach does indeed remember exactly where the machine was when you stopped. Even if you turn off your PC. When I reboot and restart mach the machine coordinates are right where I left it and if I haven't moved the machine by hand no more re zeroing is needed after verifying. I am trying to get the habit of moving my machine to g54 home prior to shutdown that way even if by some chance machine coordinates boot up other than zero you can ref all home in g54 from that spot.

Since my machine has no hand wheels to move things with power off this seems to work pretty well.
  
Reply With Quote
Old
  (#22)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-24-2020, 09:48 AM

Quote:
Originally Posted by JC View Post
Very nice video thank you. I am really starting to grasp the whole home and offset strategy.

Where did you get the GUI? It looks nothing like the mach3 screens I'm used to.

Also I'm a little confused about the reason for setting machine coordinates in g53. If you sync G54 with the machine coordinates and soft limits aren't you accomplishing the same thing? Without having to ever type any commands? G54 then becomes a mirror of g53 and is the defacto home, you just burn the offset for other uses but there's plenty more to use.

Also my experience is that unless you have a power failure not allowing you to exit mach normally or move your machine manually after shut down that Mach does indeed remember exactly where the machine was when you stopped. Even if you turn off your PC. When I reboot and restart mach the machine coordinates are right where I left it and if I haven't moved the machine by hand no more re zeroing is needed after verifying. I am trying to get the habit of moving my machine to g54 home prior to shutdown that way even if by some chance machine coordinates boot up other than zero you can ref all home in g54 from that spot.

Since my machine has no hand wheels to move things with power off this seems to work pretty well.
-The gui link is in the video description on YouTube. I super like that interface compared to the standard Mach 3 one. Edit, here it is: http://www.thecncwoodworker.com/mach3.html
-My machine also remembers the g54-g59 offsets upon turning off mach3/computer, but not machine coordinates.
-The reason to use machine coordinates for the machine home, machine soft limits, g28 position, safe z height, etc, is because that is what machine coordinates are for. They are specifically reserved for those functions. Meant to be set once and then never touched again, unless something physically changes on your machine. They never change when you put in a new part and zero xyz to the new part. If you figured out a way not to use them, and instead use g54 for everything, that's all good. As you say a million ways to skin a cat But that is not the intended function of g54-g59.

Actually now that I typed this, do you use soft limits? Using g54 I don't believe you can. On my machine, when I shut down and restart, Mach does indeed remember what the g54 position was, but the machine coordinates (g53) are all reset to zero. So that would mean soft limits could never work (as they are set in machine coordinates), neither could go to safe z, etc. You're leaving good functionality on the table if you don't home your machine using machine coordinates, IMO
  
Reply With Quote
Old
  (#23)
JC
The Thread Stops Here
JC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond repute
 
Status: Offline
Posts: 12,613
vCash: 500
iTrader: 28 / 100%
Join Date: Oct 2011
Location: PNW
   
05-24-2020, 09:55 AM

Quote:
Originally Posted by iusedtoberich View Post
-The gui link is in the video description on YouTube. I super like that interface compared to the standard Mach 3 one. Edit, here it is: http://www.thecncwoodworker.com/mach3.html
-My machine also remembers the g54-g59 offsets upon turning off mach3/computer, but not machine coordinates.
-The reason to use machine coordinates for the machine home, machine soft limits, g28 position, safe z height, etc, is because that is what machine coordinates are for. They are specifically reserved for those functions. Meant to be set once and then never touched again, unless something physically changes on your machine. They never change when you put in a new part and zero xyz to the new part. If you figured out a way not to use them, and instead use g54 for everything, that's all good. As you say a million ways to skin a cat But that is not the intended function of g54-g59.

Actually now that I typed this, do you use soft limits? Using g54 I don't believe you can. On my machine, when I shut down and restart, Mach does indeed remember what the g54 position was, but the machine coordinates (g53) are all reset to zero. So that would mean soft limits could never work (as they are set in machine coordinates), neither could go to safe z, etc. You're leaving good functionality on the table if you don't home your machine using machine coordinates, IMO
I do have soft limits set up and by having g54 set at zero machine coordinates they work well. And machine coordinates are remembered because they are in fact the g54 offset. It seems to me you zero your machine alot with your indicator and block needlessly.

I probably watched this video 6 times before I got it. https://www.youtube.com/watch?v=zFk_U3yqrks&t=94s

He never mentions g53 at all which is why I needed clarification when you guys started talking about it.

Us retards can learn anything but we can't do it quickly.

Last edited by JC; 05-24-2020 at 09:58 AM.
  
Reply With Quote
Old
  (#24)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-24-2020, 10:03 AM

If it works then keep it

I think I watched that video also a while back. Iíll try to watch it again soon as I canít remember what was on it. Cnc definitely is a steep learning curve. I have a long way to go!
  
Reply With Quote
Old
  (#25)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-24-2020, 07:37 PM

Quote:
Originally Posted by JC View Post
I do have soft limits set up and by having g54 set at zero machine coordinates they work well. And machine coordinates are remembered because they are in fact the g54 offset. It seems to me you zero your machine alot with your indicator and block needlessly.

I probably watched this video 6 times before I got it. https://www.youtube.com/watch?v=zFk_U3yqrks&t=94s

He never mentions g53 at all which is why I needed clarification when you guys started talking about it.

Us retards can learn anything but we can't do it quickly.
Yikes, I just finished watching that video. Holy moly that was hard to follow. I'm of course biased, but I think my video with the phone held in one hand and the mouse on the other was way easier to understand

I think his video would have been easier to follow if he showed the physical machine along with the screen.

So, I think I see what you and he are doing now. You are syncing up G54 with the machine coordinates, so they both show 0,0,0 at the same time. If that is the case, you never use G54 for actual machining, correct? You do all of your machining in G55-G59?

The scene in the video when he turned off the software and then turned it back on, and it showed the same G54 and G55 from before he turned it off, mine does that as well. But then he presses "go to zero" (which moves the table in G54, his current work offset). Once his "virtual table" has moved to 0,0,0 in G54, he hits the machine coord button a few times toggling it on and off. When it is displaying the G54 offset, the DRO reads 0,0,0. When it is displaying machine ccordinates, the DRO also reads 0,0,0. Then he "ref all axes".

My Mach doesn't work that way. There must be a setting that is different. I just went to my machine to triple check this. When I shut down Mach, and then restart it, it always remembers the G54-G59 offsets, but the machine coordinates are 0,0,0 upon startup. If I did what he did in that video (go to zero in g54 after restarting mach), and then switched to machine coord like he did, the DRO would not show zero in machine coord.

He also never talks in that video about an actual physical position on the machine that is home. He just says "go about 1 inch away from each endstop". I don't think that is such a great idea. If you lose steps or crash (these are hobby machines after all), then how do you get back to where you were? You just wing it and say "I'm about one inch from the axis end of travel"?
  
Reply With Quote
Old
  (#26)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-24-2020, 08:12 PM

I'm far from an expert, but I'm not sure the guy on YouTube knows what he is talking about. I just read through every single comment on his video. Several people said the same thing I did, that when they restart the software, the machine coordinates (G53) are in 0,0,0. His standard response is to try reinstalling the software? wtf?

Then a few people asked about physical limit switches. He replied to two separate people that you can't use physical limit switches and soft limits at the same time. That is definitely wrong.

And he uses the word integer in the video and in the comments section wrong. An integer is a whole number. He uses it to mean any decimal number.

I'm don't mean to nitpick, but I don't think he is an expert as he portrays to be.

<====== I'm NO expert, barely intermediate
  
Reply With Quote
Old
  (#27)
JC
The Thread Stops Here
JC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond repute
 
Status: Offline
Posts: 12,613
vCash: 500
iTrader: 28 / 100%
Join Date: Oct 2011
Location: PNW
   
05-24-2020, 08:35 PM

Quote:
Originally Posted by iusedtoberich View Post
Yikes, I just finished watching that video. Holy moly that was hard to follow. I'm of course biased, but I think my video with the phone held in one hand and the mouse on the other was way easier to understand

I think his video would have been easier to follow if he showed the physical machine along with the screen.

So, I think I see what you and he are doing now. You are syncing up G54 with the machine coordinates, so they both show 0,0,0 at the same time. If that is the case, you never use G54 for actual machining, correct? You do all of your machining in G55-G59?

The scene in the video when he turned off the software and then turned it back on, and it showed the same G54 and G55 from before he turned it off, mine does that as well. But then he presses "go to zero" (which moves the table in G54, his current work offset). Once his "virtual table" has moved to 0,0,0 in G54, he hits the machine coord button a few times toggling it on and off. When it is displaying the G54 offset, the DRO reads 0,0,0. When it is displaying machine ccordinates, the DRO also reads 0,0,0. Then he "ref all axes".

My Mach doesn't work that way. There must be a setting that is different. I just went to my machine to triple check this. When I shut down Mach, and then restart it, it always remembers the G54-G59 offsets, but the machine coordinates are 0,0,0 upon startup. If I did what he did in that video (go to zero in g54 after restarting mach), and then switched to machine coord like he did, the DRO would not show zero in machine coord.

He also never talks in that video about an actual physical position on the machine that is home. He just says "go about 1 inch away from each endstop". I don't think that is such a great idea. If you lose steps or crash (these are hobby machines after all), then how do you get back to where you were? You just wing it and say "I'm about one inch from the axis end of travel"?
Yes it was a holy hell to get the gems from it. Like I said I watched it 5 or 6 times.

Here is what I garnered. Never ever hit the ref all to home button after you set up G54 to machine coordinates unless you just started your program and you know for a fact the machine is at home where you last left it.. In fact never zero anything or machine anything in G54 once it's set to home. It's only purpose is keeping track of the axis' home positions in reference to the soft limits. It's a "burner" offset.

Always physically move your machine to home in G54 prior to shutting it down. This way when you restart or reboot you know you can hit ref all home in G54 as long as your machine hasn't been manually moved with the machine off. This way your soft limits are always valid in relation to your machine position in G54. And all other offsets are a child of the parent zero.

I have also decided to set up "ghost" offsets for the ones I want to keep using software as the homing switches. What I mean is set up your offset say in G55 then make a duplicate in G56 and machine from it. This way you never corrupt your home position in G55 by touching off from it. As soon as you zero an axis in an offset it becomes the new zero position. By creating a duplicate you can do whatever you like in that offset as far as touching off y and z and always have a backup to resync to. Once you have machined a piece in G56 and touched off in different spots you can go back to G55 and zero your machine to the original offset then switch to G56, your working offset and zero it to match in a couple of clicks to start over and corrupt it however you like from there with G55 untouched as the master copy if you will. Hope that makes sense. There are plenty of offsets available to use them any way a person sees fit.

On a final note it turns out my runaway jogging is a well known issue in Mach3 where if you release the shift key prior to the arrow key when jogging fast while in step jogging the motor keeps on trucking. Nothing to do with the chinese version. Just remember to release the arrow key before the shift key and it's all good. I have not found a solution just a lot of people identifying the problem. Apparently it's not fixed 100% in Mach4 either. I can duplicate this 100% of the time now that I understand the sequence of events that's causing it.
  
Reply With Quote
Old
  (#28)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-24-2020, 08:37 PM

Quote:
Originally Posted by JC View Post
I have watched every how to video I can find and still have trouble with this concept.

I set up soft limits to prevent my gantry and spindle from crashing in g54 and it works fine as long as you don't zero an axis. For instance if I center my x axis for ring billets by clicking on the zero x button it changes the default g54 x from the lower left corner to the center of my fourth axis permanently. Or if I touch off my router bit and click zero z the zero position for z in g 54 changes permanently and the machine position also then says zero instead of what it's supposed to tell you which is how far from home you are. Then when I hit go to zero the router slams into my table. Therefore I'm scared to death to push that button as I am never sure what's going to happen even though I know it's supposed to go back to the original home. It's supposed to be the slickest thing since sliced bread but I am not sure what to do different to stop this from occurring.


Then I tried setting up an offset in g55 mainly just for remembering the center of my ring billet rounds in the x axis which is a pain to find every time I want to cut a billet and when I clicked on reference all home and zeroed the axis' it worked perfectly. Until I went back to g54 to find every setting there was identical to what i had just set up in g55. So If I set zeros back on g54 to the lower left corner of my table and then click on g55 it's also now zeroing there. I do click save settings after every change. And then when I close Mach and come back it's just a hot mess.

On the videos I watch it works like a dream but on my machine it's a damned nightmare.

Can anyone relate to these issues in their past and found out what they were doing wrong?

Thanks,
Back to your original problem, I read it again and I'm 100% convinced its because your machine coordinates (g53) are not in a fixed physical location, and you are not homing (in G53!) to this physical location upon every single startup of the software.

Can you simply put 3 pieces of masking tape on your table for testing purposes? Draw an X on each piece. And label one piece machine home, the second G54, and the third G55.

Put a small drill bit in your spindle. Jog to the machine home tape and eyeball your drill bit above the X. Then jog down until the drill bit point is lets say approx 1" above the table. Press "ref all axes" at this location.

Then jog to the G54 tape, make sure you are in offset G54, and zero (NOT reference axis) x y z there.

Then jog to the G55 tape, make sure you are in G55 offset, and zero x y z there.

Then turn mach software off. Save the offsets pop up warning window. Then turn the mach software back on. Jog to the machine home tape (and Z about 1" above the table), and press ref all axes when you are there.

Then make sure you are in offset G54, and press go to zero. You should get to the G54 tape.

Then make sure you are in offset G55, and press go to zero. you should get to the G55 tape.

Do this whole procedure (turn mach 3 off and on) a bunch of times, and see if it works every time. If it does, and it convinces you this was the issue, then set up a real home location on your machine, and the soft limits based on that, like I did in my video. Home typically is the furthest you can go in the X negative direction, the furthest you can go in the Y negative direction, and the furthest you can go in Z positive direction. Real machines with physical home switches will have the switches at those locations. But for hobby use, you can make machine home anywhere, as long as you can get to it with precision at will.

Good luck
  
Reply With Quote
Old
  (#29)
JC
The Thread Stops Here
JC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond reputeJC has a reputation beyond repute
 
Status: Offline
Posts: 12,613
vCash: 500
iTrader: 28 / 100%
Join Date: Oct 2011
Location: PNW
   
05-24-2020, 09:25 PM

Quote:
Originally Posted by iusedtoberich View Post
Back to your original problem, I read it again and I'm 100% convinced its because your machine coordinates (g53) are not in a fixed physical location, and you are not homing (in G53!) to this physical location upon every single startup of the software.
That's sort of right but I have no desire to indicate my home position every time I start the program or set z with a block. I can find center of A axis on the Z plane with scrap wood just as quickly.

The real problem is I wasn't understanding the flow and logic of Mach in relation to home and limits. I'm starting to get it now.

Last edited by JC; 05-24-2020 at 10:20 PM.
  
Reply With Quote
Old
  (#30)
iusedtoberich
AzB Silver Member

iusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond reputeiusedtoberich has a reputation beyond repute
 
Status: Offline
Posts: 12,129
vCash: 1470
iTrader: 20 / 100%
Join Date: Mar 2004
   
05-25-2020, 06:51 AM

Quote:
Originally Posted by JC View Post
Yes it was a holy hell to get the gems from it. Like I said I watched it 5 or 6 times.

Here is what I garnered. Never ever hit the ref all to home button after you set up G54 to machine coordinates unless you just started your program and you know for a fact the machine is at home where you last left it.. In fact never zero anything or machine anything in G54 once it's set to home. It's only purpose is keeping track of the axis' home positions in reference to the soft limits. It's a "burner" offset.

Always physically move your machine to home in G54 prior to shutting it down. This way when you restart or reboot you know you can hit ref all home in G54 as long as your machine hasn't been manually moved with the machine off. This way your soft limits are always valid in relation to your machine position in G54. And all other offsets are a child of the parent zero.

I have also decided to set up "ghost" offsets for the ones I want to keep using software as the homing switches. What I mean is set up your offset say in G55 then make a duplicate in G56 and machine from it. This way you never corrupt your home position in G55 by touching off from it. As soon as you zero an axis in an offset it becomes the new zero position. By creating a duplicate you can do whatever you like in that offset as far as touching off y and z and always have a backup to resync to. Once you have machined a piece in G56 and touched off in different spots you can go back to G55 and zero your machine to the original offset then switch to G56, your working offset and zero it to match in a couple of clicks to start over and corrupt it however you like from there with G55 untouched as the master copy if you will. Hope that makes sense. There are plenty of offsets available to use them any way a person sees fit.

On a final note it turns out my runaway jogging is a well known issue in Mach3 where if you release the shift key prior to the arrow key when jogging fast while in step jogging the motor keeps on trucking. Nothing to do with the chinese version. Just remember to release the arrow key before the shift key and it's all good. I have not found a solution just a lot of people identifying the problem. Apparently it's not fixed 100% in Mach4 either. I can duplicate this 100% of the time now that I understand the sequence of events that's causing it.
I believe this will all work. Key being to use G54 as a burner offset, like you said, and never ever machining in it.

I like the idea of making ghost offsets also.

I know you don't want to make a physical home, but if you did, you could still do exactly what you are doing here, and simply never "home" the machine with blocks or indicator or whatever, unless you had a crash or lost steps.

I haven't experienced that error with the jog keys, but I will experiment with it see if I can get it to error.

One error I have seen a bunch of times, is when pressing the button for lets say G56, the button I pressed will light up, but the offset number in the line that shows the state the machine is in, will still show whatever the prior offset was. That is why in my video I was showing it in 3 places on the screen (the button I pressed, the place it says "offset number", and the line that shows all the Gcode states the machine is in). I don't know if this is a bug with Mach 3, or with the screenset I use. I'd wager Mach 3
  
Reply With Quote
Reply
Page 2 of 3 12 3

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity (Lite) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.