Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Excellent! You'll have a lot more fun once you have the servo loop
closed and can play around with precise positioning, accel/decel,
homing, etc. Remember to wire the index signal from your encoders back
to the control for eventual use for precise homing.

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Excellent! You'll have a lot more fun once you have the servo loop
closed and can play around with precise positioning, accel/decel,
homing, etc. Remember to wire the index signal from your encoders back
to the control for eventual use for precise homing.

I will definitely use the index signal. As of now, I do not even know,
yet, if my encoders work at all.

Another big chunk of work is wiring all external things like limit
switches, buttons etc.

i

Ignoramus15939 wrote:

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Excellent! You'll have a lot more fun once you have the servo loop
closed and can play around with precise positioning, accel/decel,
homing, etc. Remember to wire the index signal from your encoders back
to the control for eventual use for precise homing.

I will definitely use the index signal. As of now, I do not even know,
yet, if my encoders work at all.

Another big chunk of work is wiring all external things like limit
switches, buttons etc.

i

If you get ambitious, think about adding decel switches to allow you to
home at rapid rate most of the way.

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Excellent! You'll have a lot more fun once you have the servo loop
closed and can play around with precise positioning, accel/decel,
homing, etc. Remember to wire the index signal from your encoders back
to the control for eventual use for precise homing.

I will definitely use the index signal. As of now, I do not even know,
yet, if my encoders work at all.

Another big chunk of work is wiring all external things like limit
switches, buttons etc.

i

If you get ambitious, think about adding decel switches to allow you to
home at rapid rate most of the way.

My mill does approximately 70 IPM right now, I think that it is slow
enough for homing, no?

i

Ignoramus15939 wrote:

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Excellent! You'll have a lot more fun once you have the servo loop
closed and can play around with precise positioning, accel/decel,
homing, etc. Remember to wire the index signal from your encoders back
to the control for eventual use for precise homing.

I will definitely use the index signal. As of now, I do not even know,
yet, if my encoders work at all.

Another big chunk of work is wiring all external things like limit
switches, buttons etc.

i

If you get ambitious, think about adding decel switches to allow you to
home at rapid rate most of the way.

My mill does approximately 70 IPM right now, I think that it is slow
enough for homing, no?

i

Most likely not, but it depends on how fast your decel rate ends up set
at. You will probably want to home at around 10 IPM so you can drop down
to 1 IPM when you detect the limit switch and creep up on the index
without overshooting it. You'll figure it out once you start testing
your homing. You can also either adjust your limit switch position
slightly, or your encoder position on the motor shaft so that the index
pulse isn't too close behind the limit switch trip point.

The key thing with decel switches is that they allow you to home at
rapid speed most of the way through the homing process, which on a
machine with long travels and high rapid speeds can make a significant
difference in homing time.

"Pete C." wrote:

Ignoramus15939 wrote:

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

On 2010-07-12, Pete C. wrote:

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i

Excellent! You'll have a lot more fun once you have the servo loop
closed and can play around with precise positioning, accel/decel,
homing, etc. Remember to wire the index signal from your encoders back
to the control for eventual use for precise homing.

I will definitely use the index signal. As of now, I do not even know,
yet, if my encoders work at all.

Another big chunk of work is wiring all external things like limit
switches, buttons etc.

i

If you get ambitious, think about adding decel switches to allow you to
home at rapid rate most of the way.

My mill does approximately 70 IPM right now, I think that it is slow
enough for homing, no?

i

Most likely not, but it depends on how fast your decel rate ends up set
at. You will probably want to home at around 10 IPM so you can drop down
to 1 IPM when you detect the limit switch and creep up on the index
without overshooting it. You'll figure it out once you start testing
your homing. You can also either adjust your limit switch position
slightly, or your encoder position on the motor shaft so that the index
pulse isn't too close behind the limit switch trip point.

The key thing with decel switches is that they allow you to home at
rapid speed most of the way through the homing process, which on a
machine with long travels and high rapid speeds can make a significant
difference in homing time.

Crappy ASCII art for homing sequence:


----------|----------|---------| (home)
(rapid) ^ (slow) ^ (creep) ^
D L I
e i n
c m d
e i e
l t x

You rapid travel in the home direction until you hit the decel switch
about an inch out from the limit switch. When you hit the decel switch
you drop from rapid to slow until you hit the limit switch. When you hit
the limit switch you drops to creep for ~ 1/2 rev until you reach the
index signal at which point you stop and zero/home the axis.

Obviously if the axis happens to be near the home end at the start, the
decel setup doesn't make much difference, but if the axis is a few feet
from home, being able to rapid most of that distance saves a lot of
time.

....
You rapid travel in the home direction until you hit the decel switch
about an inch out from the limit switch. When you hit the decel switch
you drop from rapid to slow until you hit the limit switch. When you hit
the limit switch you drops to creep for ~ 1/2 rev until you reach the
index signal at which point you stop and zero/home the axis.

The home procedure with a galil card is different. First it homes off only a
home switch and an encoder index pulse on each axis

1. rapid till NC home switch opens.
2. reverse slow till home switch closes
3. creep till index pulse made.

This is occurring on all axis simultaneously. If you shut down anywhere near
home it only takes a few seconds.

Karl

Karl Townsend wrote:

...
You rapid travel in the home direction until you hit the decel switch
about an inch out from the limit switch. When you hit the decel switch
you drop from rapid to slow until you hit the limit switch. When you hit
the limit switch you drops to creep for ~ 1/2 rev until you reach the
index signal at which point you stop and zero/home the axis.

The home procedure with a galil card is different. First it homes off only a
home switch and an encoder index pulse on each axis

1. rapid till NC home switch opens.
2. reverse slow till home switch closes
3. creep till index pulse made.

This is occurring on all axis simultaneously. If you shut down anywhere near
home it only takes a few seconds.

Karl

That's a similar process really. It's basically using a decel switch as
the home switch, and needs to have enough travel after that decel/home
switch to avoid crashing into the limit when rapiding in to home. One
presumes that this setup also includes a home offset, so that axis zero
is just off the limit and not +1" out at the decel/home switch.

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

...
You rapid travel in the home direction until you hit the decel switch
about an inch out from the limit switch. When you hit the decel switch
you drop from rapid to slow until you hit the limit switch. When you
hit
the limit switch you drops to creep for ~ 1/2 rev until you reach the
index signal at which point you stop and zero/home the axis.

The home procedure with a galil card is different. First it homes off
only a
home switch and an encoder index pulse on each axis

1. rapid till NC home switch opens.
2. reverse slow till home switch closes
3. creep till index pulse made.

This is occurring on all axis simultaneously. If you shut down anywhere
near
home it only takes a few seconds.

Karl

That's a similar process really. It's basically using a decel switch as
the home switch, and needs to have enough travel after that decel/home
switch to avoid crashing into the limit when rapiding in to home. One
presumes that this setup also includes a home offset, so that axis zero
is just off the limit and not +1" out at the decel/home switch.

The X axis home on lathes is nowhere near a limit. You don't want to go
clear to the back of the lathe to home it.

At least on my machines decel switches aren't used. Instead softlimits are
used to prevent motion out-of-bounds. They allow for a barrier in the work
zone like a lathe chuck. Just more than one way to skin a cat.

Karl

Karl, just curious, do you do CNC retrofits for money? As in, "I will
set up your machine with a new control for $XXXXXX.XX"? Or do you buy,
retrofit and sell machines?

i

Karl Townsend wrote:

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

...
You rapid travel in the home direction until you hit the decel switch
about an inch out from the limit switch. When you hit the decel switch
you drop from rapid to slow until you hit the limit switch. When you
hit
the limit switch you drops to creep for ~ 1/2 rev until you reach the
index signal at which point you stop and zero/home the axis.

The home procedure with a galil card is different. First it homes off
only a
home switch and an encoder index pulse on each axis

1. rapid till NC home switch opens.
2. reverse slow till home switch closes
3. creep till index pulse made.

This is occurring on all axis simultaneously. If you shut down anywhere
near
home it only takes a few seconds.

Karl

That's a similar process really. It's basically using a decel switch as
the home switch, and needs to have enough travel after that decel/home
switch to avoid crashing into the limit when rapiding in to home. One
presumes that this setup also includes a home offset, so that axis zero
is just off the limit and not +1" out at the decel/home switch.

The X axis home on lathes is nowhere near a limit. You don't want to go
clear to the back of the lathe to home it.

Yes, it makes no difference where along the axis you home, as long as
you know where that point is.


At least on my machines decel switches aren't used. Instead softlimits are
used to prevent motion out-of-bounds. They allow for a barrier in the work
zone like a lathe chuck. Just more than one way to skin a cat.

Softlimits don't work when you are not sure of your position, such as
when you are homing.

Pete C. wrote:
Ignoramus15939 wrote:

If you get ambitious, think about adding decel switches to allow you to
home at rapid rate most of the way.
My mill does approximately 70 IPM right now, I think that it is slow
enough for homing, no?

EMC2 has a two-stage or 3-stage homing sequence. It runs at a high
speed toward the switch, reverses and then approaches the switch slower,
then can search for the index pulse from the encoder. So, as long as
the initial search is slow enough that the reversal doesn't overtax the
machine or run past the safe limit beyond the switch, you can make the
initial search as fast as you like. All 3 speeds can be set in the
..ini file.

Jon

"Ignoramus20495" wrote in message
...
Karl, just curious, do you do CNC retrofits for money? As in, "I will
set up your machine with a new control for $XXXXXX.XX"? Or do you buy,
retrofit and sell machines?

i
I'm too slow an electrician and millwright to refit for money. I consult by
the hour for control programming. I also buy used control equipment, test
it, and resell. And I get a commission on any software I sell. All of this
is just a sideline.

Karl

On 2010-07-12, Karl Townsend wrote:

"Ignoramus20495" wrote in message
...
Karl, just curious, do you do CNC retrofits for money? As in, "I will
set up your machine with a new control for $XXXXXX.XX"? Or do you buy,
retrofit and sell machines?

i
I'm too slow an electrician and millwright to refit for money. I consult by
the hour for control programming. I also buy used control equipment, test
it, and resell. And I get a commission on any software I sell. All of this
is just a sideline.

Sounds like a great sideline. What kind of control programming are you
referring to, just curious.

i

On 2010-07-12, Jon Elson wrote:
Pete C. wrote:
Ignoramus15939 wrote:

If you get ambitious, think about adding decel switches to allow you to
home at rapid rate most of the way.
My mill does approximately 70 IPM right now, I think that it is slow
enough for homing, no?

EMC2 has a two-stage or 3-stage homing sequence. It runs at a high
speed toward the switch, reverses and then approaches the switch slower,
then can search for the index pulse from the encoder. So, as long as
the initial search is slow enough that the reversal doesn't overtax the
machine or run past the safe limit beyond the switch, you can make the
initial search as fast as you like. All 3 speeds can be set in the
.ini file.

This sounds like a perfect implementation. Thanks. I will try to hook
up one encoder to your board tonight.

i

"Ignoramus20495" wrote in message
...
On 2010-07-12, Karl Townsend wrote:

"Ignoramus20495" wrote in message
...
Karl, just curious, do you do CNC retrofits for money? As in, "I will
set up your machine with a new control for $XXXXXX.XX"? Or do you buy,
retrofit and sell machines?

i
I'm too slow an electrician and millwright to refit for money. I consult
by
the hour for control programming. I also buy used control equipment, test
it, and resell. And I get a commission on any software I sell. All of
this
is just a sideline.

Sounds like a great sideline. What kind of control programming are you
referring to, just curious.

i

Camsoft and Galil

Karl

On Mon, 12 Jul 2010 14:15:01 -0500, "Karl Townsend"
wrote the following:


"Ignoramus20495" wrote in message
...
Karl, just curious, do you do CNC retrofits for money? As in, "I will
set up your machine with a new control for $XXXXXX.XX"? Or do you buy,
retrofit and sell machines?

i
I'm too slow an electrician and millwright to refit for money. I consult by
the hour for control programming. I also buy used control equipment, test
it, and resell. And I get a commission on any software I sell. All of this
is just a sideline.

Yabbut, your real job is giving away (but not shipping) bushels of
apples, isn't it, Karl?

--

EXPLETIVE: A balm, usually applied verbally in hindsight,
which somehow eases those pains and indignities following
our every deficiency in foresight.

"Pete C." wrote:

Karl Townsend wrote:

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

...
You rapid travel in the home direction until you hit the decel switch
about an inch out from the limit switch. When you hit the decel switch
you drop from rapid to slow until you hit the limit switch. When you
hit
the limit switch you drops to creep for ~ 1/2 rev until you reach the
index signal at which point you stop and zero/home the axis.

The home procedure with a galil card is different. First it homes off
only a
home switch and an encoder index pulse on each axis

1. rapid till NC home switch opens.
2. reverse slow till home switch closes
3. creep till index pulse made.

This is occurring on all axis simultaneously. If you shut down anywhere
near
home it only takes a few seconds.

Karl

That's a similar process really. It's basically using a decel switch as
the home switch, and needs to have enough travel after that decel/home
switch to avoid crashing into the limit when rapiding in to home. One
presumes that this setup also includes a home offset, so that axis zero
is just off the limit and not +1" out at the decel/home switch.

The X axis home on lathes is nowhere near a limit. You don't want to go
clear to the back of the lathe to home it.

Yes, it makes no difference where along the axis you home, as long as
you know where that point is.

I should add that if your home point is not at the end of an axis
travel, your homing routine needs to have the intelligence to reverse
and search for home in the other direction if it encounters a limit
switch instead of a home switch.



At least on my machines decel switches aren't used. Instead softlimits are
used to prevent motion out-of-bounds. They allow for a barrier in the work
zone like a lathe chuck. Just more than one way to skin a cat.

Softlimits don't work when you are not sure of your position, such as
when you are homing.

"Larry Jaques" wrote in message
...
On Mon, 12 Jul 2010 14:15:01 -0500, "Karl Townsend"
wrote the following:


"Ignoramus20495" wrote in message
...
Karl, just curious, do you do CNC retrofits for money? As in, "I will
set up your machine with a new control for $XXXXXX.XX"? Or do you buy,
retrofit and sell machines?

i
I'm too slow an electrician and millwright to refit for money. I consult
by
the hour for control programming. I also buy used control equipment, test
it, and resell. And I get a commission on any software I sell. All of this
is just a sideline.

Yabbut, your real job is giving away (but not shipping) bushels of
apples, isn't it, Karl?

I haven't had a real job since 1991. Right now, we're giving away (but not
shipping) garden vegetables out of Julie's high tunnel. We just finished
strawberries, and then a break until apples.

Karl

Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i


Since I'm getting a timeout on your server, the picture is really lousy today

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

On 2010-07-12, Wes wrote:
Ignoramus15939 wrote:

Sorry for a lousy picture.

http://igor.chudov.com/projects/Brid...d-Up-Computer/

Encoder cable is next for tonight.

i


Since I'm getting a timeout on your server, the picture is really lousy today

Lost internet at home. I will find out what it is soon.

i

Strap sez:

"Yabbut, your real job is giving away (but not shipping) bushels of
apples, isn't it, Karl? "

Karl ain't too generous 'bout giving away any apples. He has owed me a sack, lo, these many years.

Bob Swinney




"