Z Homing

[geo0rpo]

Hello everybody!

I guess this is a very silly question..but please bare with me.

When homing the Z axis with the endstop at the top this is Zmin or Z max?

Which way is 0 on Z axis? Nozzle up, or nozzle touching the pcb?

Also in the dual nozzle scenario do I need both Z endstops?

Is there an example with the dual head?

Thanks.

[ma...@makr.zone]

https://github.com/openpnp/openpnp/wiki/Machine-Axes#the-openpnp-coordinate-system

> but please bare with me.

English is a dangerous language ;-)

Verb

1.

bare - lay bare; "bare your breasts"; "bare your feelings" uncover, expose - remove all or part of one's clothes to show one's body; "uncover your belly"; "The man exposed himself in the subway"

https://idioms.thefreedictionary.com/bear+with+me

_Mark

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[geo0rpo]

I thought bear was a big brown wild animal :)

So this means that with the specific dual head the endstop at the top  is the Zmax end after homing Z I set the max Z value as the current Z position. Right?

And of course I only need one endstop. Right?

Thanks again.

[ma...@makr.zone]

With dual nozzle shared Z axis you typically home in the middle, i.e. your switch would engage when the nozzle is balanced.

I specifically improved Smoothieware to do that and if you loaded my firmware, you already have this.

https://makr.zone/adding-mid-axis-homing-to-smoothieware/359/

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/8d206a9f-12e6-48f0-951d-6934a1fc983cn%40googlegroups.com.

[geo0rpo]

Yes I have your firmware!!!

But then I whenever the endstop is engaged I will get error hit limit etc. No?

Is there an example setup?

Thanks.

[geo0rpo]

Also in order to use the nozzle tip runout I guess I need endstops on both rotational nozzles. Right?

[ma...@makr.zone]

Maybe ask @Mike, he was my testing expert (I only have a single nozzle machine).

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/b98c21be-9b87-448c-b0c5-d956f41cb073n%40googlegroups.com.

[ma...@makr.zone]

No. You can re-do the calibration every time a nozzle is loaded or at least when the machine is homed, so the machine does not need to know a physical zero rotation.

https://github.com/openpnp/openpnp/wiki/Nozzle-Tip-Calibration-Setup#automatic-recalibration

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/b2d3ae39-a575-471b-84ba-52b90359683dn%40googlegroups.com.

[Mike Menci]

Hi

I preference soft end-stops if you are on Smoothie controller . 

http://smoothieware.org/endstops

BR, 

Mike

***************************Disclaimer**

On 16 Jan 2021, at 21.53, ma...@makr.zone wrote:



To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/63ee9fc6-46a4-014f-b95f-dea31bb7416a%40makr.zone.

[Duncan Ellison]

Hi (George?),

I probably have most experience in the group on this specific topic.  I have two machines, both using the 'China' head and both are building boards fine.

Here are some hints:

1. You MUST use _Mark's firmware on the Smoothieboard.  This is not optional for this scenario (IMHO), there is code in here that supports your use case that is not (and probably never will be) incorporated into the official Smoothe builds.

2. You need only ONE of the Z sensors (advise to remove the other one) and NONE of the rotational sensors.  The key thing is that you are looking for the balance point when the sensor goes from 0 to 1 or vice versa.  This is an arbitrary point, but you can arrange it by adjusting the sensor position to be very close to the '0' position (see caveat below).

3. Don't over think the absolute accuracy of the Z position.  The springs in the nozzles will take care of small inaccuracies quite well.  In all probability with a home made machine the restraining factor here will be the flatness of the bed relative to the motion of the head, that's a harder problem to solve.

4. To answer your question about Z sign.  'zero' (for both heads) should be the balance point of the cam.  For BOTH nozzles an increasingly negative number indicates the nozzle tip going DOWN.  The negative transform in the Axis set up takes care of this for you.  Note that you will not likely get more than 23mm of downwards travel before you hit the endstops.  IMHO, this is one of the few limitations of this head design.

5. If you try to command a nozzle to make a down motion further than it is physically possible, the nozzle carriage will move until it hits the endstops and then the stepper will lose steps.  At this point all bets are off regarding the Z position, it will be at a random physical state, but the machine will think it knows where the nozzle is and since the other nozzle position is logically tied to the one you are moving, this will be incorrect as well.  This means that any XY motion you make from this point forward will have an invalid Safe Z.  If you try to move the XY position at this point you stand a very good chance of crashing the nozzle.  

6. Further to point 6.  It is very important to set up your machine to home the Z Axis before you make any XY homing movements.  The best way to achieve safety here, is to cut power to all motors BEFORE issuing a homing command.  This will cause the nozzles to retract to an approximate Z=0 state (and this taking them out of harm's way) before attempting a homing move.  This is easily achieved by issuing an M84 command in the Driver before you home.

7. Some people have attempted to set Z=0 simply by issuing an M84, letting the carriages return to the upper (physical) endstop under spring power and calling it a day.  This can work, but you will find it not especially repeatable.  One issue is that when the motor power is restored in the next move, the stepper will click to the next detent position and move the cam arm slightly to one side or the other.  If your set up is predictable in this way, then you could simply then apply a fudge offset to correct for this, but I don't recommend this approach.

8. There is a shared physical upper endstop (the bolt with the plastic/ rubber covering) for the nozzle carriages.  Depending on the manufacturing tolerances of your head, you will find that you hit this endstop before the cam arm has reached the absolute zero point.  Therefore there is a deadband where the arm cam move slightly, but it has no effect on the nozzles.  This is important.  It mans that you cannot reliably set the sensor to detect the actual, real life zero balance point.  The strategy to resolve this is to set the sensor to detect a KNOWN, BUT NOT ZERO position close to the upper stop point.  Let Smoothie think that this is the Z Home for the purposes of autodetecting, then tell it that the home is actually xxx.xx mm further up from that.  You will have to figure out what the xxx.xx mm figure is.  If I'm not being clear about this, the critical point is that you can't reliably sense an exact point where the movement is physically constrained by the endstop.

Note for people with 'Peter's' type heads:  This doesn't apply to you as both nozzles have an equal and opposite motion with no constrained middle position and therefore no deadband.

9.  In my case, a homing sequence consists of :

a) Cut power to Z stepper, let both nozzles return to approximately Z=0

b) Home 'left' until the endstop now knowing the nozzles are out of harm's way

c) Home 'back' until the endstop

d) OK, we are now at the nominal 0,0, we know there are no nozzle hazards here, so bounce 5mm off the endstops and issue another home command 

e) Homing now complete, set every to 0,0,0

I'll try to pull my config files for you, but bear in mind that you shouldn't just blindly copy them, make sure you know what each bit is doing before you apply it.

Duncan

[Duncan Ellison]

Here are three files you might find useful:

SmoothieBoard config.txt

Gcode for driver 

Optional script which resets the z to the actual 0 position after the homing is complete.

[geo0rpo]

Hello everybody!

Duncan really thanks for taking the time to explain all this stuff to me. Appreciated!

I expect to receive the dual head today or tomorrow and test it.

Some things are not so clear to me but I will try to study your setup and of course ask again :)

Thanks again to all of you.

[Trinh Dinh Huu]

Hi  Duncan Ellison

When my computer ran, I had an error in Z axis. I followed "Issues and solution".

Position_Report_reger I use issues and solutions, the function is as follows

^.*X:(?<X>-?\d+\.\d+) Y:(?<Y>-?\d+\.\d+) .*A:(?<A>-?\d+\.\d+) B:(?<B>-?\d+\.\d+).*

Vào CN, 17 thg 1, 2021 vào lúc 20:40 Duncan Ellison <duncan_...@colnewater.com> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/2186b634-4bdd-45ca-a2d0-8a69fdbae4ccn%40googlegroups.com.

--

Đinh Hữu Trình

TDC Bắc Giang

Điện thoại 0978691222; 0912851598

[ma...@makr.zone]

Hi Trinh

It seems you have two controllers. You Z seems to be mapped to a different one.

Is this correct? If yes, you need to let Issues&Solutions handle both controllers.

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/CAKDs3YzdU%2BmbSwAG0y4szZjy4XXyD8C4y5EeonAJ8SwE3Mvn%2BA%40mail.gmail.com.

[Trinh Dinh Huu]

hi 

ma...@makr.zone

I am building machine 2 smoothier controllers. I followed the Issues & Solutions instructions and accepted. But it seems that my incorrect settings lead to miss Z reporting as debugging.
In the position_report_reger part I tried to add Z part for each controller however it failed.
So my machine can only move x and y and part z has not been set up correctly. Or help me fix it

Vào Th 3, 19 thg 1, 2021 vào lúc 14:36 ma...@makr.zone <ma...@makr.zone> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/1e54d5ff-c465-8248-c98c-afafb98be774%40makr.zone.

[Trinh Dinh Huu]

I done Creater the POSITION_REPORT_REGEX, for all the axes of that controller at once and using the Axis Letters as the regex group names: 

^.*X:(?<X>-?\d+\.\d+) Y:(?<Y>-?\d+\.\d+) Z2:(?<Z2>-?\d+\.\d+) A:(?<A>-?\d+\.\d+) B:(?<B>-?\d+\.\d+).*  controller 2

^.* Z2:(?<Z2>-?\d+\.\d+) A:(?<A>-?\d+\.\d+) B:(?<B>-?\d+\.\d+).*   controller 1

but the machine is working error. and I use issues and solution the hint is to lose Z

  ^.*X:(?<X>-?\d+\.\d+) Y:(?<Y>-?\d+\.\d+)  A:(?<A>-?\d+\.\d+) B:(?<B>-?\d+\.\d+).*  

^.*A:(?<A>-?\d+\.\d+) B:(?<B>-?\d+\.\d+).*   

When coming home, the debug reports missed Z1 and Z2 locations

Vào Th 3, 19 thg 1, 2021 vào lúc 21:12 Trinh Dinh Huu <dinhhu...@gmail.com> đã viết:

[ma...@makr.zone]

Please check, if the Z axis is assigned to a driver:

https://github.com/openpnp/openpnp/wiki/Machine-Axes#controller-settings

And if the Nozzle is assigned a Z axis:

https://github.com/openpnp/openpnp/wiki/Mapping-Axes

You could also send the machine.xml

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/CAKDs3YxLJVz7avhVyY3hP7%3D5B%2Bah35nYkGmBaSDOr%2B2GK1Ef2A%40mail.gmail.com.

[Trinh Dinh Huu]

Hi Mark.

i sent file machine.xml 

Vào Th 3, 19 thg 1, 2021 vào lúc 22:28 ma...@makr.zone <ma...@makr.zone> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/2d63f391-9c62-56f2-7f06-6d77ad5735b8%40makr.zone.

[ma...@makr.zone]

Hi Trinh

You have modeled the Z axes as two independent axes. It this correct? Normally they are shared (using one motor to drive two nozzles), using something like this

Image: Pick and place head dual nozzle by Betz Technik.

You have only one Z ReferenceControllerAxis and then one or two transformed axes:

https://github.com/openpnp/openpnp/wiki/Transformed-Axes

Even if you have two independent Axes, you cannot give them a letter Z1 and Z2. G-code does not work like this. The "1" would be interpreted as part of the coordinate.

The allowed axis letters are X Y Z A B C D U V W

Smoothie supports X Y Z A B C (and D on the STM32 port).

I will add a check for that in Issues & Solutions, so it will be caught in the future.

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/CAKDs3YwP%3DCxVGdjPvw-NKt_ftD3W4_mjrzo36KD53-ub4Lk0DA%40mail.gmail.com.

[Trinh Dinh Huu]

Thanks Mark. 

I will change z1 : Z and z2: D and try. 

Vào 14:04, Th 4, 20 thg 1, 2021 ma...@makr.zone <ma...@makr.zone> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/d0b72a40-d684-0555-c93a-3e0eac0486d7%40makr.zone.

[ma...@makr.zone]

On Smoothie you should use the driver letters in a continuous sequence with no gaps:

Probably X Y Z A B

These are technically the wrong letters, but that does not matter. Make sure to use my firmware.

https://makr.zone/smoothieware-new-firmware-for-pnp/500/

_Mark

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/CAKDs3YyL_zVvnCDCiCFwmdg%3Dr8DKijKZzktrxA9Nm%2Bveyksmfg%40mail.gmail.com.

[Trinh Dinh Huu]

Thanks Mark.

Vào Th 4, 20 thg 1, 2021 vào lúc 14:18 ma...@makr.zone <ma...@makr.zone> đã viết:

To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/3905fbbe-e1fd-929b-2f81-ac082cbae9c4%40makr.zone.

[geo0rpo]

Hello friends.

Finally the dual head arrived and it is mounted on my machine.

both A & B motors rotate properly and the Z motor homes OK.

I have set the left endstop as Zmin and if I give positive Z values the left nozzle comes down to the table. I hope this is correct.

Please see my axis setup.

X,Y,Z, 2 rotational for the 2 nozzles and 2 virtual for the fiducial camera already assigned to the camera even if I do not understand why.

Now I need help. What more must I setup for the dual head to work?

Also which one is the zero. The camera or one of the nozzles?

I am very anxious to see it work :)))

Thanks! 

[geo0rpo]

OK, I have success...I guess..

But when I try to pick up a part I get the message cannot find vacuum actuator A1.

There is no A1 actuator!

[geo0rpo]

OK, basic problems:

The pump turns ON after the nozzle picks up the part.

Also the nozzle does not wait for the X-Y move to complete before getting down to the strip feeder.

[Clemens Koller]

Hello, geo0rpo.

On 22/01/2021 21.52, geo0rpo wrote:
> I have set the left endstop as Zmin and if I give positive Z values the left nozzle comes down to the table. I hope this is correct.

I am not sure if I understood you correctly. In my case (Liteplacer + TinyG), Z+ is pointing away from the table, which is opposite to yours.
The upper limit switch is the home switch. The Z-axis home is about 42mm above the table.

Clemens

On 22/01/2021 21.52, geo0rpo wrote:
> Hello friends.
> Finally the dual head arrived and it is mounted on my machine.
> both A & B motors rotate properly and the Z motor homes OK.
> I have set the left endstop as Zmin and if I give positive Z values the left nozzle comes down to the table. I hope this is correct.
>
> Please see my axis setup.
> X,Y,Z, 2 rotational for the 2 nozzles and 2 virtual for the fiducial camera already assigned to the camera even if I do not understand why.
>
> Now I need help. What more must I setup for the dual head to work?
> Also which one is the zero. The camera or one of the nozzles?
>
> I am very anxious to see it work :)))
>
> Thanks! 
>

> axis.jpg

>
>
> head.jpg
>
> On Wednesday, January 20, 2021 at 11:33:46 AM UTC+2 dinhhu...@gmail.com wrote:
>
> Thanks Mark.

> image.png
>
> Vào Th 4, 20 thg 1, 2021 vào lúc 14:18 ma...@makr.zone <ma...@makr.zone> đã viết:
>
> On Smoothie you should use the driver letters in a continuous sequence with no gaps:
>
> Probably X Y Z A B
>
> These are technically the wrong letters, but that does not matter. Make sure to use my firmware.
>

> https://makr.zone/smoothieware-new-firmware-for-pnp/500/ <https://makr.zone/smoothieware-new-firmware-for-pnp/500/>

>
> _Mark
>
> Am 20.01.2021 um 08:13 schrieb Trinh Dinh Huu:
>> Thanks Mark. 
>> I will change z1 : Z and z2: D and try. 
>>
>> Vào 14:04, Th 4, 20 thg 1, 2021 ma...@makr.zone <ma...@makr.zone> đã viết:
>>
>> Hi Trinh
>>
>> You have modeled the Z axes as two independent axes. It this correct? Normally they are shared (using one motor to drive two nozzles), using something like this
>>

>> Peters HeadImage: Pick and place head dual nozzle by Betz Technik <https://www.betztechnik.ca/store/p34/Pick_and_Place_head_-_dual_nozzle_-_OpenPnP_compatible.html#>.

>>
>> You have only one Z ReferenceControllerAxis and then one or two transformed axes:
>>

>> https://github.com/openpnp/openpnp/wiki/Transformed-Axes <https://github.com/openpnp/openpnp/wiki/Transformed-Axes>

>>
>> Even if you have two independent Axes, you cannot give them a letter Z1 and Z2. G-code does not work like this. The "1" would be interpreted as part of the coordinate.
>>
>> The allowed axis letters are X Y Z A B C D U V W
>>
>> Smoothie supports X Y Z A B C (and D on the STM32 port).
>>
>> I will add a check for that in Issues & Solutions, so it will be caught in the future.
>>
>> _Mark
>>
>>
>>
>>
>> Am 20.01.2021 um 02:51 schrieb Trinh Dinh Huu:
>>> Hi Mark.
>>> i sent file machine.xml 
>>>
>>> Vào Th 3, 19 thg 1, 2021 vào lúc 22:28 ma...@makr.zone <ma...@makr.zone> đã viết:
>>>
>>> Please check, if the Z axis is assigned to a driver:
>>>

>>> https://github.com/openpnp/openpnp/wiki/Machine-Axes#controller-settings <https://github.com/openpnp/openpnp/wiki/Machine-Axes#controller-settings>

>>>
>>> And if the Nozzle is assigned a Z axis:
>>>

>>> https://github.com/openpnp/openpnp/wiki/Mapping-Axes <https://github.com/openpnp/openpnp/wiki/Mapping-Axes>

>>>
>>> You could also send the machine.xml
>>>
>>> _Mark
>>>
>>>
>>> Am 19.01.2021 um 15:12 schrieb Trinh Dinh Huu:
>>>> hi 
>>>>
>>>>
>>>> ma...@makr.zone
>>>>
>>>> I am building machine 2 smoothier controllers. I followed the Issues & Solutions instructions and accepted. But it seems that my incorrect settings lead to miss Z reporting as debugging.
>>>> In the position_report_reger part I tried to add Z part for each controller however it failed.
>>>> So my machine can only move x and y and part z has not been set up correctly. Or help me fix it
>>>>
>>>> Vào Th 3, 19 thg 1, 2021 vào lúc 14:36 ma...@makr.zone <ma...@makr.zone> đã viết:
>>>>
>>>> Hi Trinh
>>>>
>>>> It seems you have two controllers. You Z seems to be mapped to a different one.
>>>>
>>>> Is this correct? If yes, you need to let Issues&Solutions handle both controllers.
>>>>
>>>> _Mark
>>>>
>>>>
>>>> Am 19.01.2021 um 05:03 schrieb Trinh Dinh Huu:
>>>>> Hi  Duncan Ellison
>>>>> When my computer ran, I had an error in Z axis. I followed "Issues and solution".
>>>>> Position_Report_reger I use issues and solutions, the function is as follows
>>>>> ^.*X:(?<X>-?\d+\.\d+) Y:(?<Y>-?\d+\.\d+) .*A:(?<A>-?\d+\.\d+) B:(?<B>-?\d+\.\d+).*

>>>>> image.png
>>>>>
>>>>> Vào CN, 17 thg 1, 2021 vào lúc 20:40 Duncan Ellison <duncan_...@colnewater.com> đã viết:
>>>>>
>>>>> Here are three files you might find useful:
>>>>>
>>>>> SmoothieBoard config.txt
>>>>>
>>>>> Gcode for driver 
>>>>>
>>>>> Optional script which resets the z to the actual 0 position after the homing is complete.
>>>>>
>>>>>
>>>>>
>>>>> On Sunday, 17 January 2021 at 12:40:41 UTC Duncan Ellison wrote:
>>>>>
>>>>> Hi (George?),
>>>>>
>>>>> I probably have most experience in the group on this specific topic.  I have two machines, both using the 'China' head and both are building boards fine.
>>>>>
>>>>> Here are some hints:
>>>>>

>>>>> 1. You *MUST *use _Mark's firmware on the Smoothieboard.  This is not optional for this scenario (IMHO), there is code in here that supports your use case that is not (and probably never will be) incorporated into the official Smoothe builds.

>>>>>
>>>>> 2. You need only ONE of the Z sensors (advise to remove the other one) and NONE of the rotational sensors.  The key thing is that you are looking for the balance point when the sensor goes from 0 to 1 or vice versa.  This is an arbitrary point, but you can arrange it by adjusting the sensor position to be very close to the '0' position (see caveat below).
>>>>>
>>>>> 3. Don't over think the absolute accuracy of the Z position.  The springs in the nozzles will take care of small inaccuracies quite well.  In all probability with a home made machine the restraining factor here will be the flatness of the bed relative to the motion of the head, that's a harder problem to solve.
>>>>>
>>>>> 4. To answer your question about Z sign.  'zero' (for both heads) should be the balance point of the cam.  For BOTH nozzles an increasingly negative number indicates the nozzle tip going DOWN.  The negative transform in the Axis set up takes care of this for you.  Note that you will not likely get more than 23mm of downwards travel before you hit the endstops.  IMHO, this is one of the few limitations of this head design.
>>>>>

>>>>> 5. If you try to command a nozzle to make a down motion further than it is physically possible, the nozzle carriage will move until it hits the endstops and then the stepper will lose steps.  At this point all bets are off regarding the Z position, it will be at a random physical state, but the machine will think it knows where the nozzle is and since the other nozzle position is logically tied to the one you are moving, this will be incorrect as well.  *This means that any XY motion you make from this point forward will have an invalid Safe Z*.  If you try to move the XY position at this point you stand a very good chance of crashing the nozzle.  
>>>>>
>>>>> 6. Further to point 6.  *It is very important to set up your machine to home the Z Axis before you make any XY homing movements*.  The best way to achieve safety here, is to cut power to all motors BEFORE issuing a homing command.  This will cause the nozzles to retract to an approximate Z=0 state (and this taking them out of harm's way) before attempting a homing move.  This is easily achieved by issuing an M84 command in the Driver before you home.

>>>>>
>>>>> 7. Some people have attempted to set Z=0 simply by issuing an M84, letting the carriages return to the upper (physical) endstop under spring power and calling it a day.  This can work, but you will find it not especially repeatable.  One issue is that when the motor power is restored in the next move, the stepper will click to the next detent position and move the cam arm slightly to one side or the other.  If your set up is predictable in this way, then you could simply then apply a fudge offset to correct for this, but I don't recommend this approach.
>>>>>

>>>>> 8. There is a shared physical upper endstop (the bolt with the plastic/ rubber covering) for the nozzle carriages.  Depending on the manufacturing tolerances of your head, you will find that you hit this endstop before the cam arm has reached the absolute zero point.  Therefore there is a deadband where the arm cam move slightly, but it has no effect on the nozzles.  *This is important*.  It mans that you cannot reliably set the sensor to detect the actual, real life zero balance point.  The strategy to resolve this is to set the sensor to detect a KNOWN, BUT NOT ZERO position close to the upper stop point.  Let Smoothie think that this is the Z Home for the purposes of autodetecting, then tell it that the home is actually xxx.xx mm further up from that.  You will have to figure out what the xxx.xx mm figure is.  If I'm not being clear about this, the critical point is that you can't reliably sense an exact point where the movement is

>>>>> physically constrained by the endstop.
>>>>>
>>>>> Note for people with 'Peter's' type heads:  This doesn't apply to you as both nozzles have an equal and opposite motion with no constrained middle position and therefore no deadband.
>>>>>
>>>>> 9.  In my case, a homing sequence consists of :
>>>>>
>>>>> a) Cut power to Z stepper, let both nozzles return to approximately Z=0
>>>>> b) Home 'left' until the endstop now knowing the nozzles are out of harm's way
>>>>> c) Home 'back' until the endstop
>>>>> d) OK, we are now at the nominal 0,0, we know there are no nozzle hazards here, so bounce 5mm off the endstops and issue another home command 
>>>>> e) Homing now complete, set every to 0,0,0
>>>>>
>>>>>
>>>>> I'll try to pull my config files for you, but bear in mind that you shouldn't just blindly copy them, make sure you know what each bit is doing before you apply it.
>>>>>
>>>>> Duncan
>>>>>
>>>>>
>>>>>  
>>>>>
>>>>>
>>>>>
>>>>> On Saturday, 16 January 2021 at 21:38:38 UTC mike....@gmail.com wrote:
>>>>>
>>>>> Hi
>>>>> I preference soft end-stops if you are on Smoothie controller . 
>>>>>

>>>>> http://smoothieware.org/endstops <http://smoothieware.org/endstops>

>>>>>
>>>>> BR, 
>>>>> Mike
>>>>>
>>>>> ***************************Disclaimer**
>>>>>
>>>>>
>>>>>
>>>>>> On 16 Jan 2021, at 21.53, ma...@makr.zone wrote:
>>>>>>
>>>>>> 
>>>>>>
>>>>>> No. You can re-do the calibration every time a nozzle is loaded or at least when the machine is homed, so the machine does not need to know a physical zero rotation.
>>>>>>

>>>>>> https://github.com/openpnp/openpnp/wiki/Nozzle-Tip-Calibration-Setup#automatic-recalibration <https://github.com/openpnp/openpnp/wiki/Nozzle-Tip-Calibration-Setup#automatic-recalibration>

>>>>>>
>>>>>> _Mark
>>>>>>
>>>>>> Am 16.01.2021 um 21:33 schrieb geo0rpo:
>>>>>>> Also in order to use the nozzle tip runout I guess I need endstops on both rotational nozzles. Right?
>>>>>>>
>>>>>>>
>>>>>>> On Saturday, January 16, 2021 at 10:20:17 PM UTC+2 geo0rpo wrote:
>>>>>>>
>>>>>>> Yes I have your firmware!!!
>>>>>>> But then I whenever the endstop is engaged I will get error hit limit etc. No?
>>>>>>> Is there an example setup?
>>>>>>>
>>>>>>> Thanks.
>>>>>>>
>>>>>>>
>>>>>>> On Saturday, January 16, 2021 at 10:05:39 PM UTC+2 ma...@makr.zone wrote:
>>>>>>>
>>>>>>> With dual nozzle shared Z axis you typically home in the middle, i.e. your switch would engage when the nozzle is balanced.
>>>>>>>
>>>>>>> I specifically improved Smoothieware to do that and if you loaded my firmware, you already have this.
>>>>>>>

>>>>>>> https://makr.zone/adding-mid-axis-homing-to-smoothieware/359/ <https://makr.zone/adding-mid-axis-homing-to-smoothieware/359/>

>>>>>>>
>>>>>>> _Mark
>>>>>>>
>>>>>>>
>>>>>>> Am 16.01.2021 um 20:55 schrieb geo0rpo:
>>>>>>>> I thought bear was a big brown wild animal :)
>>>>>>>> So this means that with the specific dual head the endstop at the top  is the Zmax end after homing Z I set the max Z value as the current Z position. Right?
>>>>>>>> And of course I only need one endstop. Right?
>>>>>>>> Thanks again.
>>>>>>>>
>>>>>>>>
>>>>>>>> On Saturday, January 16, 2021 at 9:24:39 PM UTC+2 ma...@makr.zone wrote:
>>>>>>>>
>>>>>>>> Axis Coordinate System
>>>>>>>>

>>>>>>>> https://github.com/openpnp/openpnp/wiki/Machine-Axes#the-openpnp-coordinate-system <https://github.com/openpnp/openpnp/wiki/Machine-Axes#the-openpnp-coordinate-system>
>>>>>>>>
>>>>>>>> /> but please bare with me./

>>>>>>>>
>>>>>>>> English is a dangerous language ;-)
>>>>>>>>

>>>>>>>> *Verb* *1.* *bare* - lay bare; "bare your breasts"; "bare your feelings"
>>>>>>>> uncover <https://www.thefreedictionary.com/uncover>, expose <https://www.thefreedictionary.com/expose> - remove all or part of one's clothes to show one's body; "uncover your belly"; "The man exposed himself in the subway"
>>>>>>>>
>>>>>>>> https://idioms.thefreedictionary.com/bear+with+me <https://idioms.thefreedictionary.com/bear+with+me>

>>>>>>>>
>>>>>>>> _Mark
>>>>>>>>
>>>>>>>>
>>>>>>>> Am 16.01.2021 um 19:44 schrieb geo0rpo:
>>>>>>>>> head2.jpg
>>>>>>>>> Hello everybody!
>>>>>>>>> I guess this is a very silly question..but please bare with me.
>>>>>>>>> When homing the Z axis with the endstop at the top this is Zmin or Z max?
>>>>>>>>>
>>>>>>>>> Which way is 0 on Z axis? Nozzle up, or nozzle touching the pcb?
>>>>>>>>>
>>>>>>>>> Also in the dual nozzle scenario do I need both Z endstops?
>>>>>>>>>
>>>>>>>>> Is there an example with the dual head?
>>>>>>>>>
>>>>>>>>> Thanks.
>>>>>>>>> --
>>>>>>>>> You received this message because you are subscribed to the Google Groups "OpenPnP" group.
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>>>>>>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/daf3d01e-ffa8-4da3-b819-fa9500ee8244n%40googlegroups.com <https://groups.google.com/d/msgid/openpnp/daf3d01e-ffa8-4da3-b819-fa9500ee8244n%40googlegroups.com?utm_medium=email&utm_source=footer>.

>>>>>>>>
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>>>>>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/8d206a9f-12e6-48f0-951d-6934a1fc983cn%40googlegroups.com <https://groups.google.com/d/msgid/openpnp/8d206a9f-12e6-48f0-951d-6934a1fc983cn%40googlegroups.com?utm_medium=email&utm_source=footer>.

>>>>>>>
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>>>>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/b2d3ae39-a575-471b-84ba-52b90359683dn%40googlegroups.com <https://groups.google.com/d/msgid/openpnp/b2d3ae39-a575-471b-84ba-52b90359683dn%40googlegroups.com?utm_medium=email&utm_source=footer>.

>>>>>> --
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>>>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/63ee9fc6-46a4-014f-b95f-dea31bb7416a%40makr.zone <https://groups.google.com/d/msgid/openpnp/63ee9fc6-46a4-014f-b95f-dea31bb7416a%40makr.zone?utm_medium=email&utm_source=footer>.

>>>>>
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>>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/2186b634-4bdd-45ca-a2d0-8a69fdbae4ccn%40googlegroups.com <https://groups.google.com/d/msgid/openpnp/2186b634-4bdd-45ca-a2d0-8a69fdbae4ccn%40googlegroups.com?utm_medium=email&utm_source=footer>.

>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Đinh Hữu Trình
>>>>> TDC Bắc Giang
>>>>> Điện thoại 0978691222; 0912851598
>>>>> --
>>>>> You received this message because you are subscribed to the Google Groups "OpenPnP" group.
>>>>> To unsubscribe from this group and stop receiving emails from it, send an email to openpnp+u...@googlegroups.com.

>>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/CAKDs3YzdU%2BmbSwAG0y4szZjy4XXyD8C4y5EeonAJ8SwE3Mvn%2BA%40mail.gmail.com <https://groups.google.com/d/msgid/openpnp/CAKDs3YzdU%2BmbSwAG0y4szZjy4XXyD8C4y5EeonAJ8SwE3Mvn%2BA%40mail.gmail.com?utm_medium=email&utm_source=footer>.

>>>> --
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>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/1e54d5ff-c465-8248-c98c-afafb98be774%40makr.zone <https://groups.google.com/d/msgid/openpnp/1e54d5ff-c465-8248-c98c-afafb98be774%40makr.zone?utm_medium=email&utm_source=footer>.

>>>>
>>>>
>>>>
>>>> --
>>>> Đinh Hữu Trình
>>>> TDC Bắc Giang
>>>> Điện thoại 0978691222; 0912851598
>>>> --
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>>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/CAKDs3YxLJVz7avhVyY3hP7%3D5B%2Bah35nYkGmBaSDOr%2B2GK1Ef2A%40mail.gmail.com <https://groups.google.com/d/msgid/openpnp/CAKDs3YxLJVz7avhVyY3hP7%3D5B%2Bah35nYkGmBaSDOr%2B2GK1Ef2A%40mail.gmail.com?utm_medium=email&utm_source=footer>.

>>> --
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>>> To view this discussion on the web visit https://groups.google.com/d/msgid/openpnp/2d63f391-9c62-56f2-7f06-6d77ad5735b8%40makr.zone <https://groups.google.com/d/msgid/openpnp/2d63f391-9c62-56f2-7f06-6d77ad5735b8%40makr.zone?utm_medium=email&utm_source=footer>.

>>>
>>>
>>>
>>> --
>>> Đinh Hữu Trình
>>> TDC Bắc Giang
>>> Điện thoại 0978691222; 0912851598
>>> --
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>> --
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>>
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>
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>
>
>
> --
> Đinh Hữu Trình
> TDC Bắc Giang
> Điện thoại 0978691222; 0912851598
>
> --
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