Idea needed on howto configure machine with 2 z-axis
- ahhkoch
- Offline
- New Member
-
Less
More
- Posts: 18
- Thank you received: 0
17 Aug 2018 06:43 - 17 Aug 2018 06:47 #116192
by ahhkoch
Idea needed on howto configure machine with 2 z-axis was created by ahhkoch
Hi,
i am looking around for an idea for my new concept: I have a classic 3-axis-machine, but with a second Independent z-axis. Idea is simple: produce 2 parts at same time. thatswhy i have some questions and i hope to get some hints here:
homing
both z-axis are independtly controlled by a stepper and with separate reference-switches. Maybe the new "Joints" Feature can help here.
tool lenghts-sensor
both z-axis can use same TLS (sits in the middle of both z-axis). TLS-macro would be: move to tls-position for Z1 and do G38 for Z1, move to tls-position for Z2 and do G38 again. i think this is not possible for Joints, only for axis, right? Here i am stuck...
Only idea i have, is to abuse the TLS as homing Switch (would be sufficient for me). But how can i modify the homing procedure because i need an offset move in xy to get Z1 and Z2 over same tls for "homing".
Gcode/auto-mode
In auto-mode both Z-Axis shall be moved as one Z-Axis (in sync)...Do i have to do this in gcode or is there a way to do this in linuxcnc?
Greetings
Andreas
i am looking around for an idea for my new concept: I have a classic 3-axis-machine, but with a second Independent z-axis. Idea is simple: produce 2 parts at same time. thatswhy i have some questions and i hope to get some hints here:
homing
both z-axis are independtly controlled by a stepper and with separate reference-switches. Maybe the new "Joints" Feature can help here.
tool lenghts-sensor
both z-axis can use same TLS (sits in the middle of both z-axis). TLS-macro would be: move to tls-position for Z1 and do G38 for Z1, move to tls-position for Z2 and do G38 again. i think this is not possible for Joints, only for axis, right? Here i am stuck...
Only idea i have, is to abuse the TLS as homing Switch (would be sufficient for me). But how can i modify the homing procedure because i need an offset move in xy to get Z1 and Z2 over same tls for "homing".
Gcode/auto-mode
In auto-mode both Z-Axis shall be moved as one Z-Axis (in sync)...Do i have to do this in gcode or is there a way to do this in linuxcnc?
Greetings
Andreas
Last edit: 17 Aug 2018 06:47 by ahhkoch.
Please Log in or Create an account to join the conversation.
- andypugh
-
- Offline
- Moderator
-
Less
More
- Posts: 23178
- Thank you received: 4865
20 Aug 2018 13:43 #116374
by andypugh
Replied by andypugh on topic Idea needed on howto configure machine with 2 z-axis
This is logically identical to a gantry. The controller does not need to know that both Z axes have tools and spindles.
Tool length compensation is where it gets messy.
With fully independent axes you would call one Z and the other W. Then the tool table can contain both Z and W lengths and stuff should just work.
If your G-code contains only Z moves then I think that it can only use one offset from the tool table.
This might be an application for the "external offsets" experimental branch, the difference in tool lengths could be applied via a userspace HAL component (written in C or Python).
There may be other ways to do it that I haven't thought of, though.
Gantry homing to two separate tool length switches would be pretty seamless, but handling the top-of-travel limit might be tricky. (possibly wok-round-able by just declaring the axes shorter than they physically are)
Tool length compensation is where it gets messy.
With fully independent axes you would call one Z and the other W. Then the tool table can contain both Z and W lengths and stuff should just work.
If your G-code contains only Z moves then I think that it can only use one offset from the tool table.
This might be an application for the "external offsets" experimental branch, the difference in tool lengths could be applied via a userspace HAL component (written in C or Python).
There may be other ways to do it that I haven't thought of, though.
Gantry homing to two separate tool length switches would be pretty seamless, but handling the top-of-travel limit might be tricky. (possibly wok-round-able by just declaring the axes shorter than they physically are)
Please Log in or Create an account to join the conversation.
- Todd Zuercher
-
- Away
- Platinum Member
-
Less
More
- Posts: 4957
- Thank you received: 1441
20 Aug 2018 15:21 #116376
by Todd Zuercher
Replied by Todd Zuercher on topic Idea needed on howto configure machine with 2 z-axis
I have a couple of machines configured just as you describe.
I have them set up with one of the Z axis configured as W. When I am carving 2 identical parts, I have the machine configured to use some custom M-codes and some hal trickery to slave the W axis to the Z and have them move together as one Z axis.
One of the two machines I have set up uses stepper motors and the other uses servos. The servo machine has a much more complicated hal setup, but functionally the two are the same.
If you like I could post a copy of the configuration files for the stepper machine and an example g-code file that shows how the custom M-codes are used.
I have them set up with one of the Z axis configured as W. When I am carving 2 identical parts, I have the machine configured to use some custom M-codes and some hal trickery to slave the W axis to the Z and have them move together as one Z axis.
One of the two machines I have set up uses stepper motors and the other uses servos. The servo machine has a much more complicated hal setup, but functionally the two are the same.
If you like I could post a copy of the configuration files for the stepper machine and an example g-code file that shows how the custom M-codes are used.
Please Log in or Create an account to join the conversation.
- carlosbahia
- Offline
- New Member
-
Less
More
- Posts: 5
- Thank you received: 0
26 Jan 2019 17:38 #124909
by carlosbahia
Replied by carlosbahia on topic Idea needed on howto configure machine with 2 z-axis
hi my friend my name is Carlos, I wanted your help, I want to implement 2 or 3 independent spindles in my cnc machine, but to work as an ATC, an ATC is very expensive, that is when calling the tool change using one of the spindles, every time, I'm initiating in cnc linux, I saw that you already did something similar, could you help me, friend?
Please Log in or Create an account to join the conversation.
Time to create page: 0.053 seconds