Hi Dan,
A Rigid Tapping G code is not currently supported in KMotionCNC. Actually there is code in KMotionCNC for G84 that is coded to make several spindle synchronized moves, but I don't think that would work well.
We would probably be willing to add that built in functionality into KMotionCNC if we can agree on the syntax and you are willing to help debug. It seems like G84 is more standard on Fanuc and Haas. Mach3 uses it for Floating Tapping.
Of course you can use #Var Parameters, an MCode, and
a User C Program to Rigid Tap now in the same manner as Mach3. The C Program would need to be modified slightly to read the parameters rather than having Mach3 write them to UserData Memory. I can do that for you if you wish. Getting that to work correctly would be first step regardless.
Regards TK
| Group: DynoMotion |
Message: 10140 |
From: Dan |
Date: 9/5/2014 |
| Subject: Re: Tapping in KmotionCNC |
Tom,
I am game to help with this, I have done a fair amount of research into
this. I will send another email when I have time in the next couple days and let
you know my thoughts on this. But I would be glad to help how ever I can.
Dan
Sent: Thursday, September 04, 2014 12:15 PM
Subject: Re: [DynoMotion] Tapping in KmotionCNC
Hi Dan,
A
Rigid Tapping G code is not currently supported in KMotionCNC. Actually
there is code in KMotionCNC for G84 that is coded to make several spindle
synchronized moves, but I don't think that would work well.
We
would probably be willing to add that built in functionality into KMotionCNC if
we can agree on the syntax and you are willing to help debug. It seems
like G84 is more standard on Fanuc and Haas. Mach3 uses it for Floating
Tapping.
Of
course you can use #Var Parameters, an MCode, and a User C Program to Rigid Tap
now in the same manner as Mach3. The C Program would need to be modified
slightly to read the parameters rather than having Mach3 write them to UserData
Memory. I can do that for you if you wish. Getting that to work
correctly would be first step regardless.
Regards
TK
| Group: DynoMotion |
Message: 10179 |
From: Dan |
Date: 9/17/2014 |
| Subject: Re: Tapping in KmotionCNC |
Tom,
I have been
swamped with work, school and getting ready for a wedding so this is a bit
delayed. Here is what I have so far. I could be wrong but I don’t think it will
take a ton of work on your end in coding to make this happen. I need to find
some more info on the structure of the G84 command (how it is put together in
the g-code file). But from the small amount I know I think it follows the
convention of most other canned cycles.
I can test
your code when you get it done, but I have one small hangup right now. My
spindle motor went up in smoke last week and I am running on a temporary motor.
So I will not be able to do any rigid tapping testing until the new motor comes
and I get an encoder installed.
I did a fair amount of internet searching and talked to
a few friends who program CNC’s daily. Here is a compilation of what I have
found.
G Codes for tapping
G33.1
G33.2
G74 – Non rigid tapping Left Hand
G74.1 – Rigid Tapping Left Hand -
G.84 – Generic Tapping G-Code
G84.1 – Right hand Rigid tapping - Mazak
G84.2 – Right Hand rigid tapping
G84.3 – Left hand Rigid tapping
Plus there may be more and there are combinations of
G-codes to comprise different tapping cycles. Write or wrong I am thinking
either we use just G74 and G84 or have it a programmable value for an
initialization file. Where the end user would tell the KFLOP which G-code is
left hand and which is right hand.
The next thing I found was the F value of the canned
cycle can have 2 different values. One version has the F value equal to the
thread pitch (1/4-20 would be 0.050”). The second F value is an actual inches
per minute for the Z axis. This would be calculated by multiplying the thread
pitch times the spindle RPM.
The next variable is the type of tapping, old school
tapping would have been done with a automatically reversing tapping head. The
spindle turns clockwise the entire cycle and the tapping head reverses when the
Z axis retracts. Then there is the tension & compression tapping head that
allows for a non-synchronized Z axis feed. The last type is rigid tapping.
I am thinking that we use the generic G74 and G84
G-Codes like I mentioned before. Then you add a set of parameters to configure
the controller to the type of tapping that the user wants to do. Something like
this is what I a picturing.
The G-Code in the program should look something like
this, just like most other canned routines.
If the user
picks option
A1
– Z axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns clockwise for Z+ move
G74 – Not sure if tapping head supports this?
A2-
Z axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
A3-
Z axis is geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
Dan
|
|
| Group: DynoMotion |
Message: 10196 |
From: Dan |
Date: 9/24/2014 |
| Subject: Re: Tapping in KmotionCNC |
Tom,
Just a little update, I have 2 spindle motors on the way to me and I am
going to order some optical encoders this afternoon. But I want to verify
something with you first.
I have a 6000 RPM and a 8000 RPM motor coming, I was planning on using 1000
line optical encoders. I think you said the sampling rate for the encoder
channels is 1Mhz, is tat correct? I want to verify how that sampling works.
6000 RPM motor with a 1000 line encoder (4000 line w quadrature)
6000 RPM/ 60 Seconds = 100 Rotations per second
100 Rotations per second * 1000 lines per rotation = 100,000hz or 100Khz
single rate per channel
So the sampling needed for this setup is only 100Khz correct? The 4X
multiplication for the quadrature happens after the signal is sampled, right? Or
is the sampling needed 200Khz because the rising and falling edge need to be
detected?
Dan
Sent: Wednesday, September 17, 2014 8:36 AM
Subject: Re: [DynoMotion] Tapping in KmotionCNC
Tom,
I have been swamped with work,
school and getting ready for a wedding so this is a bit delayed. Here is what I
have so far. I could be wrong but I don’t think it will take a ton of work on
your end in coding to make this happen. I need to find some more info on the
structure of the G84 command (how it is put together in the g-code file). But
from the small amount I know I think it follows the convention of most other
canned cycles.
I can test your code when you
get it done, but I have one small hangup right now. My spindle motor went up in
smoke last week and I am running on a temporary motor. So I will not be able to
do any rigid tapping testing until the new motor comes and I get an encoder
installed.
I
did a fair amount of internet searching and talked to a few friends who program
CNC’s daily. Here is a compilation of what I have found.
G
Codes for tapping
G33.1
G33.2
G74 – Non rigid tapping Left Hand
G74.1 – Rigid Tapping Left Hand -
G.84 – Generic Tapping G-Code
G84.1 – Right hand Rigid tapping - Mazak
G84.2 – Right Hand rigid tapping
G84.3 – Left hand Rigid tapping
Plus there may be more and there are combinations of
G-codes to comprise different tapping cycles. Write or wrong I am thinking
either we use just G74 and G84 or have it a programmable value for an
initialization file. Where the end user would tell the KFLOP which G-code is
left hand and which is right hand.
The next thing I found was the F value of the canned
cycle can have 2 different values. One version has the F value equal to the
thread pitch (1/4-20 would be 0.050”). The second F value is an actual inches
per minute for the Z axis. This would be calculated by multiplying the thread
pitch times the spindle RPM.
The next variable is the type of tapping, old school
tapping would have been done with a automatically reversing tapping head. The
spindle turns clockwise the entire cycle and the tapping head reverses when the
Z axis retracts. Then there is the tension & compression tapping head that
allows for a non-synchronized Z axis feed. The last type is rigid tapping.
I
am thinking that we use the generic G74 and G84 G-Codes like I mentioned before.
Then you add a set of parameters to configure the controller to the type of
tapping that the user wants to do. Something like this is what I a picturing.
The G-Code in the program should look something like
this, just like most other canned routines.
If the user picks option
A1 – Z
axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns clockwise for Z+ move
G74 – Not sure if tapping head supports this?
A2- Z
axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
A3- Z
axis is geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
Dan
|
|
| Group: DynoMotion |
Message: 10201 |
From: Tom Kerekes |
Date: 9/24/2014 |
| Subject: Re: Tapping in KmotionCNC |
Hi Dan,
Actually KFLOP samples the A B Quadrature lines at 16.67MHz and performs programmable filtering and counts quadrature transitions (counts). The main limitation is that only +/-127 quadrature transitions can be counted per servo sample time of 90us. This comes out to about 1.4M
quadrature counts/sec. We spec 1.0M quadrature counts/sec which is 250K encoder lines/sec.
You should be good.
Regards TK
| Group: DynoMotion |
Message: 10491 |
From: Tom Kerekes |
Date: 11/11/2014 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
Hi Dan,
I'm not familiar with a tension/compression head. I'm assuming it provides some Z compliance so that exact synchronization is not required?
I think we could use the same Rigid Tapping sequence for it. If you don't have spindle feedback we could still used synchronized Z motion the same as if we did, but just modify the code slightly to assume the actual Spindle Position is the same as the commanded Spindle Position. The C Program here uses the commanded Spindle position (Dest) to slave the Z Motion.
Let's get "Rigid" tapping to work first calling a C Prbefore we begin modifying the Interpreter. This process will need to be modified to work with KMotionCNC instead of Mach3. The Process just involves downloading the parameters for the Tap and then running the C Program
Tap sequence. KFLOP can simply read the GCode Var Parameters directly so there is no need to put them in DROs and download them the way the Mach3 process works.
I forget how your Spindle is controlled. Before we do anything we will need to configure things (open loop?) in a manner that we can tell the Spindle Axis to Move a certain amount (few revs) and then reverse a certain amount and it should move that amount approximately. Do you know how to do this?
Let me know how much of this makes sense.
Regards TK
Have
you had any time to look into the tapping code? Even if the rigid tapping did
not get worked out yet support for G84 and G74 for a tapping head or tension and
compression tap head would be great. Right now I am using a Procunier tapping
head and using a G85 and a reaming cycle. This works but the tapping head is
huge and limits the size of part I can tap. To use a tension and compression
tapping head the same canned cycle as G85 would work as a starting point and
then reverse the spindle when the Z depth is reached. Then flip the spindle back
to the original direction once the machine has reached the retract plane.
If
you do not have time to work on this right now, can you tell me what code file/s
handle the processing of the G code canned cycles? Maybe I can give it a whirl.
As
for development of the rigid tapping code, I still have not been able to get my
motor with encoder modified and installed. I am hoping by the first of the year
now.
From: "Tom Kerekes tk@... [DynoMotion]" <DynoMotion@yahoogroups.com>
To: "DynoMotion@yahoogroups.com" <DynoMotion@yahoogroups.com>
Sent:
Wednesday, September 24, 2014 10:18 AM
Subject: Re: [DynoMotion] Tapping in KmotionCNC [2 Attachments]
[Attachment(s) from Tom Kerekes included below]
Hi Dan,
Actually KFLOP samples the A B Quadrature lines at 16.67MHz and performs programmable filtering and counts quadrature transitions (counts). The main limitation is that only +/-127 quadrature
transitions can be counted per servo sample time of 90us. This comes out to about 1.4M
quadrature counts/sec. We spec 1.0M quadrature counts/sec which is 250K encoder lines/sec.
You should be good.
Regards TK
From: "'Dan' engnerdan@... [DynoMotion]" <DynoMotion@yahoogroups.com>
To: DynoMotion@yahoogroups.com
Sent: Wednesday, September 24,
2014 5:36 AM
Subject: Re: [DynoMotion] Tapping in KmotionCNC
Tom,
Just a little update, I have 2 spindle motors on the way to me and I am
going to order some optical encoders this afternoon. But I want to verify
something with you first.
I have a 6000 RPM and a 8000 RPM motor coming, I was planning on using 1000
line optical encoders. I think you said the sampling rate for the encoder
channels is 1Mhz, is tat correct? I want to verify how that sampling works.
6000 RPM motor with a 1000 line encoder (4000 line w quadrature)
6000 RPM/ 60 Seconds = 100 Rotations per second
100 Rotations per second * 1000 lines per rotation = 100,000hz or 100Khz
single rate per channel
So the sampling needed for this setup is only 100Khz correct? The 4X
multiplication for the quadrature happens after the signal is sampled, right? Or
is the sampling needed 200Khz because the rising and falling edge need to be
detected?
Dan
Sent: Wednesday, September 17, 2014 8:36 AM
Subject: Re: [DynoMotion] Tapping in KmotionCNC
Tom,
I have been swamped with work,
school and getting ready for a wedding so this is a bit delayed. Here is what I
have so far. I could be wrong but I don’t think it will take a ton of work on
your end in coding to make this happen. I need to find some more info on the
structure of the G84 command (how it is put together in the g-code file). But
from the small amount I know I think it follows the convention of most other
canned cycles.
I can test your code when you
get it done, but I have one small hangup right now. My spindle motor went up in
smoke last week and I am running on a temporary motor. So I will not be able to
do any rigid tapping testing until the new motor comes and I get an encoder
installed.
I
did a fair amount of internet searching and talked to a few friends who program
CNC’s daily. Here is a compilation of what I have found.
G
Codes for tapping
G33.1
G33.2
G74 – Non rigid tapping Left Hand
G74.1 – Rigid Tapping Left Hand -
G.84 – Generic Tapping G-Code
G84.1 – Right hand Rigid tapping - Mazak
G84.2 – Right Hand rigid tapping
G84.3 – Left hand Rigid tapping
Plus there may be more and there are combinations of
G-codes to comprise different tapping cycles. Write or wrong I am thinking
either we use just G74 and G84 or have it a programmable value for an
initialization file. Where the end user would tell the KFLOP which G-code is
left hand and which is right hand.
The next thing I found was the F value of the canned
cycle can have 2 different values. One version has the F value equal to the
thread pitch (1/4-20 would be 0.050”). The second F value is an actual inches
per minute for the Z axis. This would be calculated by multiplying the thread
pitch times the spindle RPM.
The next variable is the type of tapping, old school
tapping would have been done with a automatically reversing tapping head. The
spindle turns clockwise the entire cycle and the tapping head reverses when the
Z axis retracts. Then there is the tension & compression tapping head that
allows for a non-synchronized Z axis feed. The last type is rigid tapping.
I
am thinking that we use the generic G74 and G84 G-Codes like I mentioned before.
Then you add a set of parameters to configure the controller to the type of
tapping that the user wants to do. Something like this is what I a picturing.
The G-Code in the program should look something like
this, just like most other canned routines.
If the user picks option
A1 – Z
axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns clockwise for Z+ move
G74 – Not sure if tapping head supports this?
A2- Z
axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
A3- Z
axis is geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
Dan
|
|
| Group: DynoMotion |
Message: 10509 |
From: Dan |
Date: 11/13/2014 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
Tom,
Yes the Tension and compression tapping head does exactly what you thought.
It is spring loaded in both extension and compression. These would be used when
there is no encoder to sync the spindle with.
My spindle currently is a Hitachi VFD, using an analog input for frequency
(speed) and 2 inputs for CW/CCW. The motor I will use for rigid tapping is a 3
HP 8000 RPM Fanuc unit from a industrial CNC, and it will be fitted with a US
Digital 500 line optical encoder. But that one needs an adapter plate made to
mount it and one made for the encoder, it will be several weeks before I get
those done.
I have been looking at the Mach3 rigid tapping code, I think for the most
part I got a handle on what is going on. But there are a couple things I am not
understanding, and I have not had time to search for answers to them. The first
is the reversing of the spindle, it looks like the spindle direction in this
code is handled by commanding a positive or negative movement of the spindle
axis, like it was a servo. Does this work with analog spindle control with a
discrete input for both forward and reverse? My second unanswered item is how to
read GCode Var Parameters
into the c program?
Here are 4 samples of the various ways the g code for tapping could be
presented.
S100 M3
G98 G84 X-1. Y1. Z-1. R0.2 F0.03125 (G-Code with Thread
Pitch, R plane is not used because of G98)
S100 M3
G98 G84 X-1. Y1. Z-1. R0.2 F3.125 (G-Code with actual
feed rate, R plane is not used because of G98)
S100 M3
G99 G84 X-1. Y1. Z-1. R0.2
F0.03125 (G-Code with Thread Pitch, R plane is used as the retract
height)
S100 M3
G99 G84 X-1. Y1. Z-1. R0.2 F3.125 (G-Code with actual
feed rate, R plane is used as the retract height)
Dan
Sent: Tuesday, November 11, 2014 2:57 PM
Subject: Re: [DynoMotion] Tapping in KmotionCNC [2
Attachments]
Hi Dan,
I'm
not familiar with a tension/compression head. I'm assuming it provides
some Z compliance so that exact synchronization is not required?
I
think we could use the same Rigid Tapping sequence for it. If you don't
have spindle feedback we could still used synchronized Z motion the same as if
we did, but just modify the code slightly to assume the actual Spindle
Position is the same as the commanded Spindle Position. The C
Program here uses the commanded Spindle position (Dest) to slave the Z
Motion.
Let's
get "Rigid" tapping to work first calling a C Prbefore we begin modifying the
Interpreter. This process will need to be modified to work with KMotionCNC
instead of Mach3. The Process just involves downloading the parameters for
the Tap and then running the C Program Tap sequence. KFLOP can simply read
the GCode Var Parameters directly so there is no need to put them in DROs and
download them the way the Mach3 process works.
I
forget how your Spindle is controlled. Before we do anything we will need
to configure things (open loop?) in a manner that we can tell the Spindle Axis
to Move a certain amount (few revs) and then reverse a certain amount and it
should move that amount approximately. Do you know how to do this?
Let
me know how much of this makes sense.
Regards
TK
Have you had any time to
look into the tapping code? Even if the rigid tapping did not get worked out yet
support for G84 and G74 for a tapping head or tension and compression tap head
would be great. Right now I am using a Procunier tapping head and using a G85
and a reaming cycle. This works but the tapping head is huge and limits the size
of part I can tap. To use a tension and compression tapping head the same canned
cycle as G85 would work as a starting point and then reverse the spindle when
the Z depth is reached. Then flip the spindle back to the original direction
once the machine has reached the retract plane.
If you do not have time to
work on this right now, can you tell me what code file/s handle the processing
of the G code canned cycles? Maybe I can give it a whirl.
As for development of the
rigid tapping code, I still have not been able to get my motor with encoder
modified and installed. I am hoping by the first of the year now.
| Group: DynoMotion |
Message: 10510 |
From: Tom Kerekes |
Date: 11/13/2014 |
| Subject: Re: Tapping in KmotionCNC |
Hi Dan,
Regarding Spindle Control. I'm not sure if you want to go through the trouble of interfacing the Hitachi VFD if you are going to soon change it out. To do the reversing
with a Relay you would need a few line C program to watch the Servo Output, send the magnitude to a DAC, and sets the relay output bit based on the sign.
Regarding accessing GCode Vars from KFLOP. See the example KFLOPtoPCCmdExamples.c The example uploads 3 numbers (doubles) to GCode Vars, runs an Interpreter command to add one to the first Var, then reads them back into KFLOP and prints them.
// put 3 double values in the persist vars
SetUserDataDouble(10,123.456);
SetUserDataDouble(11,1000.0);
SetUserDataDouble(12,999.9);
// transfer up to the
GCode Vars
SetVars(100,3,10); // Upload 3 to GCode 100 from persist 10
MDI("#100 = [#100 + 1]");
// read them back into different persist Vars
GetVars(100,3,13); // Download 3 from GCode 100 to persist 13
printf("%f %f %f\n",GetUserDataDouble(13),GetUserDataDouble(14),GetUserDataDouble(15));
Regards TK
From: "'Dan' engnerdan@... [DynoMotion]" <DynoMotion@yahoogroups.com>
To: DynoMotion@yahoogroups.com
Sent: Thursday, November 13, 2014 11:34 AM
Subject: Re: [DynoMotion] Tapping in KmotionCNC
Tom,
Yes the Tension and compression tapping head does exactly what you thought.
It is spring loaded in both extension and compression. These would be used when
there is no encoder to sync the spindle with.
My spindle currently is a Hitachi VFD, using an analog input for frequency
(speed) and 2 inputs for CW/CCW. The motor I will use for rigid tapping is a 3
HP 8000 RPM Fanuc unit from a industrial CNC, and it will be fitted with a US
Digital 500 line optical encoder. But that one needs an adapter plate made to
mount it and one made for the encoder, it will be several weeks before I get
those done.
I have been looking at the Mach3 rigid tapping code, I think for the most
part I got a handle on what is going on. But there are a couple things I am not
understanding, and I have not had time to search for answers to them. The first
is the reversing of the spindle, it looks like the spindle direction in this
code is handled by commanding a positive or negative movement of the spindle
axis, like it was a servo. Does this work with analog spindle control with a
discrete input for both forward and reverse? My second unanswered item is how to
read GCode Var Parameters
into the c program?
Here are 4 samples of the various ways the g code for tapping could be
presented.
S100 M3
G98 G84 X-1. Y1. Z-1. R0.2 F0.03125 (G-Code with Thread
Pitch, R plane is not used because of G98)
S100 M3
G98 G84 X-1. Y1. Z-1. R0.2 F3.125 (G-Code with actual
feed rate, R plane is not used because of G98)
S100 M3
G99 G84 X-1. Y1. Z-1. R0.2
F0.03125 (G-Code with Thread Pitch, R plane is used as the retract
height)
S100 M3
G99 G84 X-1. Y1. Z-1. R0.2 F3.125 (G-Code with actual
feed rate, R plane is used as the retract height)
Dan
Sent: Tuesday, November 11, 2014 2:57 PM
Subject: Re: [DynoMotion] Tapping in KmotionCNC [2
Attachments]
Hi Dan,
I'm
not familiar with a tension/compression head. I'm assuming it provides
some Z compliance so that exact synchronization is not required?
I
think we could use the same Rigid Tapping sequence for it. If you don't
have spindle feedback we could still used synchronized Z motion the same as if
we did, but just modify the code slightly to assume the actual Spindle
Position is the same as the commanded Spindle Position. The C
Program here uses the commanded Spindle position (Dest) to slave the Z
Motion.
Let's
get "Rigid" tapping to work first calling a C Prbefore we begin modifying the
Interpreter. This process will need to be modified to work with KMotionCNC
instead of Mach3. The Process just involves downloading the parameters for
the Tap and then running the C Program Tap sequence. KFLOP can simply read
the GCode Var Parameters directly so there is no need to put them in DROs and
download them the way the Mach3 process works.
I
forget how your Spindle is controlled. Before we do anything we will need
to configure things (open loop?) in a manner that we can tell the Spindle Axis
to Move a certain amount (few revs) and then reverse a certain amount and it
should move that amount approximately. Do you know how to do this?
Let
me know how much of this makes sense.
Regards
TK
Have you had any time to
look into the tapping code? Even if the rigid tapping did not get worked out yet
support for G84 and G74 for a tapping head or tension and compression tap head
would be great. Right now I am using a Procunier tapping head and using a G85
and a reaming cycle. This works but the tapping head is huge and limits the size
of part I can tap. To use a tension and compression tapping head the same canned
cycle as G85 would work as a starting point and then reverse the spindle when
the Z depth is reached. Then flip the spindle back to the original direction
once the machine has reached the retract plane.
If you do not have time to
work on this right now, can you tell me what code file/s handle the processing
of the G code canned cycles? Maybe I can give it a whirl.
As for development of the
rigid tapping code, I still have not been able to get my motor with encoder
modified and installed. I am hoping by the first of the year now.
From: "Tom
Kerekes tk@... [DynoMotion]"
<DynoMotion@yahoogroups.com>
To: "DynoMotion@yahoogroups.com"
<DynoMotion@yahoogroups.com>
Sent: Wednesday, September 24, 2014 10:18
AM
Subject: Re: [DynoMotion]
Tapping in KmotionCNC [2 Attachments]
[Attachment(s) from Tom Kerekes included
below]
Hi Dan,
Actually
KFLOP samples the A B Quadrature lines at 16.67MHz and performs programmable
filtering and counts quadrature transitions (counts). The main limitation
is that only +/-127 quadrature transitions can be counted per servo sample time
of 90us. This comes out to about 1.4M quadrature counts/sec. We spec
1.0M quadrature counts/sec which is 250K encoder lines/sec.
You
should be good.
Regards
TK
From:
"'Dan' engnerdan@... [DynoMotion]" <DynoMotion@yahoogroups.com>
To:
DynoMotion@yahoogroups.com
Sent: Wednesday, September 24, 2014 5:36
AM
Subject: Re:
[DynoMotion] Tapping in KmotionCNC
Tom,
Just a little update, I have 2 spindle motors on the way to me and I am
going to order some optical encoders this afternoon. But I want to verify
something with you first.
I have a 6000 RPM and a 8000 RPM motor coming, I was planning on using 1000
line optical encoders. I think you said the sampling rate for the encoder
channels is 1Mhz, is tat correct? I want to verify how that sampling works.
6000 RPM motor with a 1000 line encoder (4000 line w quadrature)
6000 RPM/ 60 Seconds = 100 Rotations per second
100 Rotations per second * 1000 lines per rotation = 100,000hz or 100Khz
single rate per channel
So the sampling needed for this setup is only 100Khz correct? The 4X
multiplication for the quadrature happens after the signal is sampled, right? Or
is the sampling needed 200Khz because the rising and falling edge need to be
detected?
Dan
Sent: Wednesday, September 17, 2014 8:36 AM
Subject: Re: [DynoMotion] Tapping in
KmotionCNC
Tom,
I have been swamped with work, school and
getting ready for a wedding so this is a bit delayed. Here is what I have so
far. I could be wrong but I don’t think it will take a ton of work on your end
in coding to make this happen. I need to find some more info on the structure of
the G84 command (how it is put together in the g-code file). But from the small
amount I know I think it follows the convention of most other canned cycles.
I can test your code when you get it done, but
I have one small hangup right now. My spindle motor went up in smoke last week
and I am running on a temporary motor. So I will not be able to do any rigid
tapping testing until the new motor comes and I get an encoder installed.
I did a fair
amount of internet searching and talked to a few friends who program CNC’s
daily. Here is a compilation of what I have found.
G Codes for
tapping
G33.1
G33.2
G74 – Non rigid
tapping Left Hand
G74.1 – Rigid
Tapping Left Hand -
G.84 – Generic
Tapping G-Code
G84.1 – Right
hand Rigid tapping - Mazak
G84.2 – Right
Hand rigid tapping
G84.3 – Left
hand Rigid tapping
Plus there may
be more and there are combinations of G-codes to comprise different tapping
cycles. Write or wrong I am thinking either we use just G74 and G84 or have it a
programmable value for an initialization file. Where the end user would tell the
KFLOP which G-code is left hand and which is right hand.
The next thing I
found was the F value of the canned cycle can have 2 different values. One
version has the F value equal to the thread pitch (1/4-20 would be 0.050”). The
second F value is an actual inches per minute for the Z axis. This would be
calculated by multiplying the thread pitch times the spindle RPM.
The next
variable is the type of tapping, old school tapping would have been done with a
automatically reversing tapping head. The spindle turns clockwise the entire
cycle and the tapping head reverses when the Z axis retracts. Then there is the
tension & compression tapping head that allows for a non-synchronized Z axis
feed. The last type is rigid tapping.
I am thinking
that we use the generic G74 and G84 G-Codes like I mentioned before. Then you
add a set of parameters to configure the controller to the type of tapping that
the user wants to do. Something like this is what I a picturing.
The G-Code in
the program should look something like this, just like most other canned
routines.
If the user picks option
A1 – Z axis is not
geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns clockwise for Z+ move
G74 – Not sure if tapping head supports this?
A2-
Z axis is not geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
A3-
Z axis is geared to the spindle
G84 – Spindle turns clockwise for Z – move
G84 – Spindle turns counter clockwise for Z+ move
G74 – Spindle turns counter clockwise for Z- move
G74 – Spindle turns clockwise for Z+ move
Dan
|
|
| Group: DynoMotion |
Message: 10511 |
From: Dan |
Date: 11/13/2014 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
Tom,
Thanks for the quick reply.
I am not changing the Hitachi motor drive, just the motor. But your
explanation confirms what I was thinking. That is I would need to manually
change the direction in the C program.
I will look at that code example and see if I can wrap my head around how
it is working. I will keep you posted on my results
Thanks,
Dan
Sent: Thursday, November 13, 2014 1:52 PM
Subject: Re: [DynoMotion] Tapping in KmotionCNC [2
Attachments]
Hi Dan,
Regarding
Spindle Control. I'm not sure if you want to go through the trouble of
interfacing the Hitachi VFD if you are going to soon change it out. To do
the reversing with a Relay you would need a few line C program to watch the
Servo Output, send the magnitude to a DAC, and sets the relay output bit based
on the sign.
Regarding
accessing GCode Vars from KFLOP. See the example
KFLOPtoPCCmdExamples.c The example uploads 3 numbers (doubles) to GCode
Vars, runs an Interpreter command to add one to the first Var, then reads them
back into KFLOP and prints them.
// put 3 double values in the persist vars
SetUserDataDouble(10,123.456);
SetUserDataDouble(11,1000.0);
SetUserDataDouble(12,999.9);
//
transfer up to the GCode Vars
SetVars(100,3,10); //
Upload 3 to GCode 100 from persist 10
MDI("#100 = [#100 +
1]");
//
read them back into different persist Vars
GetVars(100,3,13); // Download 3 from GCode 100 to persist 13
printf("%f %f
%f\n",GetUserDataDouble(13),GetUserDataDouble(14),GetUserDataDouble(15));
Regards
TK
| Group: DynoMotion |
Message: 10628 |
From: engnerdan |
Date: 12/2/2014 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
Tom, I am still picking away at the code for rigid tapping. I thinking I have figured out the example of how to read the g code into a C program. But I have more questions before I can move on.
I have attached a non-working bit of code, only to show what I came up with in the main() section for retrieving the g code variables into the C program.
Question 1. Using the "GetVars" function you had in your code examples. I don't see how variations in the g code format can be taken into account.
Example I am basing the code I write on a g code like looking like this G84 X-1. Y1. Z-1. R0.2 F0.03125
But what if the X and Y values are not given or if the "R" value is left out? G84 Z-1. R0.2 F0.03125
G84 X-1. Y1. Z-1. F0.03125
Question 2. How do I get the Z value from which the tapping starts? Like in this example code, we are starting 1.25" above the Z0 plane and tapping from there down to Z0.5.
Example code G01 X1.5 Y1.5 Z1.25 G84 Xa.5 Y1.5 Z0.5 R.2 F0.03125
Question 3. How do I read in the current commanded spindle RPM into the c program. So if the g code tells KMotionCNC S100 but the operator has the spindle override at 2X. The commanded speed is not 200RPM, is there a way read in what KMotionCNC thinks the spindle RPM is supposed to be?
Thanks, Dan ---In DynoMotion@yahoogroups.com, <engnerdan@...> wrote : Tom, Thanks for the quick reply. I am not changing the Hitachi motor drive, just the motor. But your
explanation confirms what I was thinking. That is I would need to manually
change the direction in the C program. I will look at that code example and see if I can wrap my head around how
it is working. I will keep you posted on my results Thanks, Dan Sent: Thursday, November 13, 2014 1:52 PM Subject: Re: [DynoMotion] Tapping in KmotionCNC [2
Attachments] Hi Dan,
Regarding
Spindle Control. I'm not sure if you want to go through the trouble of
interfacing the Hitachi VFD if you are going to soon change it out. To do
the reversing with a Relay you would need a few line C program to watch the
Servo Output, send the magnitude to a DAC, and sets the relay output bit based
on the sign.
Regarding
accessing GCode Vars from KFLOP. See the example
KFLOPtoPCCmdExamples.c The example uploads 3 numbers (doubles) to GCode
Vars, runs an Interpreter command to add one to the first Var, then reads them
back into KFLOP and prints them.
// put 3 double values in the persist vars
SetUserDataDouble(10,123.456);
SetUserDataDouble(11,1000.0);
SetUserDataDouble(12,999.9);
//
transfer up to the GCode Vars
SetVars(100,3,10); //
Upload 3 to GCode 100 from persist 10
MDI("#100 = [#100 +
1]");
//
read them back into different persist Vars
GetVars(100,3,13); // Download 3 from GCode 100 to persist 13
printf("%f %f
%f\n",GetUserDataDouble(13),GetUserDataDouble(14),GetUserDataDouble(15));
Regards TK
| Group: DynoMotion |
Message: 10635 |
From: Tom Kerekes |
Date: 12/3/2014 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
Hi Dan,
No that isn't the way to read GCode into a C Program. It is reading GCode Variables. GCode Variables are different than the "words" in a Gcode line.
The function:
GetVars(100,3,13); // Download 3 from GCode 100 to persist 13
Reads 3 GCode Variables #100 #101 #102 into KFLOP double persist variables 13, 14, 15.
Are you familiar with GCode Variables? They are sort of like memory variables on a calculator. The Interpreter has 5400 of them. Some have special functionality (values > 5000) but many are for general use.
As I said before as a first step let's not worry about creating the G84 Gcode or modifying the GCode Interpreter yet. Let's do that after we demonstrate that we can successfully do rigid tapping. Let's start doing things just like what works in Mach3 for Rigid Tapping. This will also allow us to be on the same page as to what types and variations of Rigid tapping you think are required. See:
In this case we write GCode to put all the necessary parameters for the Tap into GCode Variables with something like:
#10=20 (TPI - Threads per inch)
#11=700 (Forward Cutting RPM)
#12=1000 (Retract RPM)
#13=0.75 (Z depth Total inches)
#14=0.2 (Z depth Forward per Motion)
#15=0.05 (Z depth Retract per Motion)
Let's assume this is sufficient to define what the Rigid Tapping Sequence should do.
Next we can invoke an M code to run a program in KFLOP to read all these parameters and do the Tap. The Mach3 example used Mcode 84 because it is the same number as G84 that is often used for Rigid Tapping. But KMotionCNC doesn't allow M84 to be used so let's use M100 instead which is able to be configured to run a C Program in KFLOP. Note this is only a test. Later after everything works we will change the GCode Interpreter so that a line of G84 can do the same thing.
So after the above GCode we would add:
M100
Set the Tool Setup to configure M100 to execute your program "DLW - Rigid Tapping.c"
The first thing the C program should do is download the GCode Vars. Mach3 downloaded those 6 values into persist Variables 12-23 (which as double words would be 6-11). So let's download them to the same KFLOP persist variables with:
GetVars(10,6,6); // Download 6 values from GCode #10-15 to persist 6-11
Then lets print the 6 values to see if that much is working so far:
printf("%f %f %f %f %f %f\n",GetUserDataDouble(6),GetUserDataDouble(7),GetUserDataDouble(8),GetUserDataDouble(9),GetUserDataDouble(10),GetUserDataDouble(11));
Please try that as a first step and let me know how much of this makes sense. Regards TK
| Group: DynoMotion |
Message: 14231 |
From: engnerdan |
Date: 12/6/2016 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
|
Tom,
I am going to drive back into this rigid tapping work (after a two year delay). I will do everything you talked about in your previous reply and post back here.
In the time since I started this topic I have run several commercial/industrial CNC mills and tried to observe how they handle rigid tapping. Which I have found they are blocking out any feedrate overrides or feedrate and spindle overrides when they enter a rigid tapping cycle. Additionally they are disabling a feedhold being issued while the tapping cycle is happening. Is this already implemented in KMOTION for a lathe installation with single point threading? If so is it possible to block a feedrate or spindle override (set it to 100%) and block a feedhold from a C-program?
Dan
|
|
| Group: DynoMotion |
Message: 14232 |
From: Tom Kerekes |
Date: 12/6/2016 |
| Subject: Re: Tapping in KmotionCNC |
Hi Dan,
No I believe most of that would need to be added if needed.
I would think that you may want SSO for single point Threading.
Rigid Tapping is performed by a C Program basically performing an
Independent Spindle Motion ie. MoveRelAtVel(SPINDLE_AXIS,
Dist*TPI*CNTS_PER_REV, Rate*TPI*CNTS_PER_REV); while the Z axis is
following the spindle using Independent MoveExp() calls. I
believe this should run unaffected by SSO or FRO changes.
Feedhold might also make sense while rigid tapping. Feedhold only
affects the Axes included in the Coordinated Motion System.
Regards
TK
Tom,
I am going to drive back into this rigid tapping work
(after a two year delay). I will do everything you talked
about in your previous reply and post back here.
In the time since I started this topic I have run several
commercial/industrial CNC mills and tried to observe how
they handle rigid tapping. Which I have found they are
blocking out any feedrate overrides or feedrate and
spindle overrides when they enter a rigid tapping cycle.
Additionally they are disabling a feedhold being issued
while the tapping cycle is happening. Is this already
implemented in KMOTION for a lathe installation with
single point threading? If so is it possible to block a
feedrate or spindle override (set it to 100%) and block a
feedhold from a C-program?
Dan
|
|
| Group: DynoMotion |
Message: 14236 |
From: mmurray70@hotmail.com |
Date: 12/6/2016 |
| Subject: Re: Tapping in KmotionCNC [2 Attachments] |
Hi Dan,
I blocked feedhold from my toolchange program. I setup my machine so pushing feedhold external button sets a variable, and i set a persist.UserData variable in my toolchange program to prevent feedhold, and i check both these variables in my forever loop and then apply feedhold.
Another huge bonus of doing it this way is it remembers if you push feedhold while executing a C program. It seemed to ignore feedhold for me if it was pushed while spindle was ramping up. And pushing it before while toolchanging would have caused my toolchanger to crash. Now i can push feedhold during a spindle ramp up and safely during a toolchange without messing it up, and feedhold is applied automatically on the first move. Heres the code i used, may not be perfect, but it works:
if (ReadBit(1038)) persist.UserData[160] = 1; // If Feedhold button pushed set feedhold variable to 1 // If Fhold var is 1, any axis moves, toolchanger done and job active then stop motion if (persist.UserData[160] == 1 && CheckDoneXYZABC && !persist.UserData[161] && JOB_ACTIVE) StopCoordinatedMotion(); if (ReadBit(1037)) // if cycle start button pushed { persist.UserData[160] = 0; // Disable feedhold variable ResumeCoordinatedMotion(); // Resume motion }
Also, all the machines i have used (fanuc and mazak) also ignore feed and speed overrides and feedholds. Once you start you cant stop. Good luck with it.
Mark |
|
| Group: DynoMotion |
Message: 14240 |
From: engnerdan |
Date: 12/7/2016 |
| Subject: Re: Tapping in KmotionCNC |
|
Your timing with this reply is ironic because at the same time I was implementing the same thing for a different reason. I have not cared for how the ExternalButtons.c example code handled the FeedHold operation because if I accidentally double pressed the FeedHold switch I was no longer in FeedHold.
So last night I rewrote the example code and planned to share it today. But while I was falling asleep last night I realized that having a bit for the feedhold state was beneficial for other purposes, like a tower light to indicate the machine is in a feedhold.
Its early and I am not wrapping my head around your other state tests in your code, but I will look at it again later.
-Dan
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