[Emc-users] A clarifying post that might help another victum of poor Chinese docs.

[Gene Heskett]

On Saturday 26 December 2020 18:54:09 Gene Heskett wrote:

A clarifying post for the list archive that might help someone else.

After reading several different versions of the manual I've found online, 
and killing another tree for hard copy BIG enough to read, it becomes 
obvious that the common point reference for the speed input AND the 
MultiFunction terminal labeled VO in my unit, all use the AGM terminal 
as a commom reference, while the FWD(RUN in my case)/REV are referenced 
to the DCM terminal.

Said another way, the AGM terminal MUST be grounded to the 7i76 GND bus 
in order to give the A2D's on the first 4 inputs a ground to read the VO 
output against, and it was not the way I had it wired, it was floating. 
The controls don't care. This is discovered only after a carefull 
perusal of the block wiring only partially shown in the manuals.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] for PCW

[Gene Heskett]

On Saturday 26 December 2020 18:21:01 Gene Heskett wrote:

> On Friday 25 December 2020 15:27:39 Peter C. Wallace wrote:
> > On Fri, 25 Dec 2020, Gene Heskett wrote:
> > > Date: Fri, 25 Dec 2020 15:03:43 -0500
> > > From: Gene Heskett 
> > > Reply-To: "Enhanced Machine Controller (EMC)"
> > > 
> > > To: emc-users@lists.sourceforge.net
> > > Subject: [Emc-users] for PCW
> > >
> > > Greetings and Merry Christmas.
> > >
> > > The 7i76 manual has mention of modes 0, 1, and 2 for reading the
> > > analog voltages applied to the first 4 inputs.
> > >
> > > But no place in that lengthy manual does it mention how to switch
> > > it so this mode 1 is enabled so as to enable that ability.
> >
> > The hostmot2 man page has the information
> >
> > basically you set the mode with a token/value pair
> > in the hm2_xxx driver command line like:
> >
> > sserial_port_0=23xx
> >
> > (this sets sserial port 0 channel 0 to mode 2 and channel 1 to mode
> > 3)
>
> Ok, but define channel. What I am getting for a 1xxx argument is
> nonsensical.
>
> At s15000 m3, I see about 6.2 volts, steady, between ACM and VO which
> is a 0-10 volt signal representing 0 to 400 HZ output. From that I
> should be able to scale it up by 60 and have an rpm to display.
>
> But at hm2_5i25.0.7i76.0.0.analogin0, I seeing at very random
> intervals, a floating point value that is 0, 97% of the time and when
> it does flash up a reading its always well under a volt. Like the
> ground reference isn't there or is very noisy. But its a dead steady
> 6.2 volts on 2 other dvm's.  So obviously I'm doing something wrong. 
> But what? I've even put a clip lead from ACM to DCM which aren't
> ohmicaly common but made no difference in how it worked for controls
> or in this analog function. I'll go back out and verify that my ground
> buss is ground, but I've no other ideas.
>
> Thanks Peter.

And it turned out the ground buss was fine. but the drain wire for one of 
the shielded cables is missconnected in the 7i76, so I'll have to 
reconfigure how I am using that cable as Iwas treating it as a ground at 
the vfd. the spindle_enable - at the other end is nowehere near a ground 
according to my scope. The end result is that cable has several volts of 
HF junk on it from the vfd.  Its long enough I can cut it off and rewire 
it, but my tummy says its feed me time. My apologies, Peter.

>  > > And it does output a 0-9.9 volt signal for a 0 to 397 HZ input on
> > >
> > > the vfd's VO terminal.  So where do I put this mysterious "mode 1"
> > > ???
> > >
> > > Thanks Peter.
> > >
> > > Cheers, Gene Heskett
> > > --
> > > "There are four boxes to be used in defense of liberty:
> > > soap, ballot, jury, and ammo. Please use in that order."
> > > -Ed Howdershelt (Author)
> > > If we desire respect for the law, we must first make the law
> > > respectable. - Louis D. Brandeis
> > > Genes Web page 
> > >
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> > Peter Wallace
> > Mesa Electronics
> >
> > (\__/)
> > (='.'=) This is Bunny. Copy and paste bunny into your
> > (")_(") signature to help him gain world domination.
> >
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
> Cheers, Gene Heskett


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Chinese VFDs with good reputations

[Gregg Eshelman via Emc-users]

I picked up a couple of 220V 1PH to 220V 3PH VFDs, rated for up to 3HP, for 
under $300 each new. Don't recall the brand and I'm not home where I can go 
look in the shop.
What I find insane is how *simple* electronic phase converters that do nothing 
but change single to three phase, doing nothing to the voltage, no speed 
adjusting, no remote control, no where to connect a braking resistor, are so 
expensive. $1500 and all it does is exactly the same thing as an old rotary 
phase converter.

So rather than a "plug and play" box for my Monarch 12CK I had to buy a fancy 
box with almost 100 settings I had to fiddle with just to get it to run the 
antique 3HP motor without hitting overload. Still have to slip the clutch a 
little in higher gears but once it's turning it's 100% solid. Adding some 
MolySlip gear lube to the headstock made it quieter and easier to get spinning.

On Saturday, December 26, 2020, 11:50:37 AM MST, John Dammeyer 
 wrote:  
 I looked at prices for a 2HP 3phase and a VFD (like Hitatchi Vectorless?) and 
found without shipping the price was approaching $600.  For less than that I 
ended up with Bergerda.  
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Re: [Emc-users] for PCW

[Gene Heskett]

On Friday 25 December 2020 15:27:39 Peter C. Wallace wrote:

> On Fri, 25 Dec 2020, Gene Heskett wrote:
> > Date: Fri, 25 Dec 2020 15:03:43 -0500
> > From: Gene Heskett 
> > Reply-To: "Enhanced Machine Controller (EMC)"
> > 
> > To: emc-users@lists.sourceforge.net
> > Subject: [Emc-users] for PCW
> >
> > Greetings and Merry Christmas.
> >
> > The 7i76 manual has mention of modes 0, 1, and 2 for reading the
> > analog voltages applied to the first 4 inputs.
> >
> > But no place in that lengthy manual does it mention how to switch it
> > so this mode 1 is enabled so as to enable that ability.
>
> The hostmot2 man page has the information
>
> basically you set the mode with a token/value pair
> in the hm2_xxx driver command line like:
>
> sserial_port_0=23xx
>
> (this sets sserial port 0 channel 0 to mode 2 and channel 1 to mode 3)
>
Ok, but define channel. What I am getting for a 1xxx argument is 
nonsensical.

At s15000 m3, I see about 6.2 volts, steady, between ACM and VO which is 
a 0-10 volt signal representing 0 to 400 HZ output. From that I should 
be able to scale it up by 60 and have an rpm to display.

But at hm2_5i25.0.7i76.0.0.analogin0, I seeing at very random intervals, 
a floating point value that is 0, 97% of the time and when it does flash 
up a reading its always well under a volt. Like the ground reference 
isn't there or is very noisy. But its a dead steady 6.2 volts on 2 other 
dvm's.  So obviously I'm doing something wrong.  But what? I've even put 
a clip lead from ACM to DCM which aren't ohmicaly common but made no 
difference in how it worked for controls or in this analog function. 
I'll go back out and verify that my ground buss is ground, but I've no 
other ideas.

Thanks Peter.

 > > And it does output a 0-9.9 volt signal for a 0 to 397 HZ input on
> > the vfd's VO terminal.  So where do I put this mysterious "mode 1"
> > ???
> >
> > Thanks Peter.
> >
> > Cheers, Gene Heskett
> > --
> > "There are four boxes to be used in defense of liberty:
> > soap, ballot, jury, and ammo. Please use in that order."
> > -Ed Howdershelt (Author)
> > If we desire respect for the law, we must first make the law
> > respectable. - Louis D. Brandeis
> > Genes Web page 
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
> Peter Wallace
> Mesa Electronics
>
> (\__/)
> (='.'=) This is Bunny. Copy and paste bunny into your
> (")_(") signature to help him gain world domination.
>
>
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Making L Type Timing pulleys.

[Gene Heskett]

On Saturday 26 December 2020 14:55:02 andy pugh wrote:

> On Sat, 26 Dec 2020 at 19:34, John Dammeyer  
wrote:
> > Making a new lower pulley with 9 teeth is out of the question.  It's
> > too small for only 9T and definitely won't fit on the 19mm motor
> > shaft.  And that's the kicker.  At almost 3/4" the pulley that goes
> > onto it has to be large enough to have a decent grip with set screws
> > onto a 6mm key.
>
> I seem to recall that it is recommended to not go below 12T anyway.
>
> I don't know much about L and XL belts, all my machines have used T5.
> T5 is available in widths from 8mm to 25mm.
> https://www.bearingboys.co.uk/T5-Section-5mm-Pitch-1224-c
>
> I also have the correct hob for making custom T5 pulleys, so that is
> one reason for _me_ to use them.
>
> You could consider ignoring the keyway, especially if the motor shafts
> have a threaded hole in the end.
>
> I have several times taken inspiration from the Trantorque bushings:
> https://uk.rs-online.com/web/p/keyless-bushes/7542545/
> However they require a huge central bore, so what I have done is
> machine the pulley bore with a taper and then pull or push in a
> sleeve.
> At various times I have used a bolt in the end of the shaft, a nut
> pulling the wedge through, or a ring of bolts to push the wedge in.
>
> Here is variation on the theme, with two tapers:
> https://bodgesoc.blogspot.com/2017/01/gears.html

That I like, a lot. I've made my own taperlock setups several times, but 
nothing that thin. Thanks for posting it.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] cnc lathe retrofit

[andy pugh]

On Sat, 26 Dec 2020 at 21:11, Gene Heskett  wrote:

> No synchros in that gearbox? I'd be getting quotes to replace it with one
> that did.

It was built in 1916. It's perfect as it is :-)

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1912


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Re: [Emc-users] Chinese VFDs with good reputations

[Gene Heskett]

On Saturday 26 December 2020 13:48:29 John Dammeyer wrote:

> I looked at prices for a 2HP 3phase and a VFD (like Hitatchi
> Vectorless?) and found without shipping the price was approaching
> $600.  For less than that I ended up with Bergerda.
>
> I'm using a Bergerda AC Servo 110SM series (1.8kW, 6NM)  on my
> spindle, currently with a cheap PWM module until I wire up a second
> BoB for step/dir control.  With PWM I get 100RPM to 3000RPM without a
> belt change.  With stepper I can have it move very very slowly.
>
> I also swapped in, for testing, a smaller 60SM series 1.27NM Bergerda
> onto the X axis.  Once I read the manual correctly I got step and
> direction working well.  The drive isn't overly large but is a bit
> bigger than the HP_UHU which runs the brushed servo motors also 1.2
> NM. This video shows it now working.  I can get 180ipm on the X axis
> just like the much bigger DC Servo. https://youtu.be/43liAVILgHY
>
> The Gecko Stepper G213V driver on the knee has now failed for the
> second time melting the connector again.  Absolutely no response from
> Gecko so it's being scrapped and FedEx tracking says my new Bergerda
> AC 80SM series servo (3.5NM) will arrive on Wednesday along with 2
> more of the small 60SM units.
>
> They aren't cheap compared to stepper motors.  In my case I get to
> remove a complete Toroidal power supply that runs only the stepper but
> is big enough for the entire mill with 60VDC motor drivers.
>
> The DC Servos and Harmonic drive (controlled with STMBL) run on a
> 105DC Toroidal power supply.  I could remove this and run the Harmonic
> off 110VAC to DC with a smaller isolation transformer.  Then I'd have
> room for the Bergerda drives. This is the MACH3 Road Runner with the
> much bigger DC Servos and the 1200 oz-in (drops to 3.5NM at 300RPM) on
> the knee. https://youtu.be/OUQzyp-3WXY
>
> I've found support and price excellent, shipping horrendous.   For
> example I found that when the spindle stopped it would sometimes sit
> with a bit of a squeal.  A quick email to Bergerda and discussion and
> we figured out which parameters to tweak.  Now it's dead quiet.  And
> much smaller than the single phase 1.5kW 2HP motor.
> http://www.autoartisans.com/mill/NewPulleys-1.jpg
>
> John Dammeyer

Looks pretty good from here, John.  You do better finish work than I and 
its obvious.
>
> > -Original Message-
> > From: Dave Cole [mailto:linuxcncro...@gmail.com]
> > Sent: December-26-20 9:44 AM
> > To: emc-users@lists.sourceforge.net
> > Subject: [Emc-users] Chinese VFDs with good reputations
> >
> > What low cost Chinese drives have you guys used with great success?
> >
> > I'm talking mostly single phase input drives.
> >
> > There are a lot of look a likes on Ebay.�� Some are dirt cheap.
> > Others not so much.
> >
> > Some specify that they are specifically for water cooled spindles,
> > etc.
> >
> > Others say almost nothing.
> >
> > Dave
> >
> >
> >
> > ___
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> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
> ___
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] cnc lathe retrofit

[Gene Heskett]

On Saturday 26 December 2020 13:36:18 andy pugh wrote:

> On Sat, 26 Dec 2020 at 16:49, Gene Heskett  
wrote:
> > Two additional questions. That 70 ohm 300 watt braking resistor just
> > walked up and rang my doorbell, so are you using one?
>
> I am not using one. It would be useful if I was, since I added
> on-the-fly gearshifting to the two speed box.

These spindles don't come with a gearbox. Plain old motors.

> The idea is that if it is in low gear and the spindle speed goes above
> 500 rpm then it disconnects the low-speed clutch and slows the motor
> down to the right speed to operate the high-speed clutch.
> Unfortunately the spindle slows faster than the motor, so they only
> really catch each other at zero-zero.
>
> If I had a braking resistor then I could slow the motor faster, and
> there would be more chance of catching the gear change.
>
> But the VFD is next to the motor, behind a panel that is only
> accessible once the lathe is pulled away from the wall.
> So I have not tried to add one.
>
> Downshifting goes a little better.
>
> I drive an old fire engine that has the same problem, if you are going
> up a steep hill, that the vehicle could climb in top or third gear, if
> you have to stop and go into first, there is no way to get out of
> first and you have to hold it to the top of the hill.

No synchros in that gearbox? I'd be getting quotes to replace it with one 
that did. Racers use an ignition killer for upshifts, leaning on the 
synchro rings kills the ignition until the rings are unloaded as the 
shift is completed. Mopar trannys from about 1932 have a different 
internal motion and are amenable to that in both directions, lean on the 
lever to downshift, tap the kill for long enough to unload the gears, 
the ignition comes back on and as the rpms build the synchro finishes 
the shift. An upshift is done the same way but the ignition isn't 
re-enabled until the shift is completed. Clutch pedal not required for 
either.

Those boxes weren't really rated for the hemi v8's so gear life isn't 
great usually breaking second gear idling along in 5 o-clock traffic, 
but never when I was busy showing the Chevies how its done. I did 140k 
miles in a 52 Chrysler Saratoga all on the same transmission case.  That 
car was the best concealed weapon ever in the stoplight grand prix once 
its m6 tranny and fluid drive were replaced with a 53 dodge od tranny.

That made the effective rear end gear 2.42/1. 30 mph per 1000 rpms in 
high overdrive, it could go the length of South Dakota at 3300 rpm in 
about 4 hours, on one 21 gallon tank of gas, getting 21+ mpg doing it. I 
knew a few tricks with those old carter carbs too. Even with a 10 foot 
2.5" straight pipe exiting under the rear axle it never got the laws 
attention. It could do anything I wanted it do except turn a corner. 
That hemi was simply too heavy, 1100 lbs hanging on a hoist. Lots of 
cast iron in that puppy.
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Checking vfd hookup question?

[Gene Heskett]

On Saturday 26 December 2020 12:35:17 Dave Cole wrote:

> I'm sure those could be made to work if they are of an acceptable Ohms
> range, but how do you mount them?
> They are just elements.
> Most braking resistors on larger machines are in cages on the top or
> side of the control panels.
> For small drives, they are oftentimes just screwed to the panel
> backplane,   But then they don't get that hot.
>
> By the time you fab the cage, you can almost buy one new with a cage
> and that is rated.

Which is what I did, but its not in a cage, its encapsulated in a 1x2 alu 
extrusion about 8" long with bolt holes in the end tabs. $29.95 + ship 
from a seller in KY. With leads long enough I can hang it on the 
plumbers strapping holding up the shelf the electrics are on above the 
6040.

> Dave
>
> On 12/24/2020 1:36 PM, Jon Elson wrote:
> > On 12/24/2020 11:43 AM, Dave Cole wrote:
> >> Automation Direct sells braking resistors.
> >> https://www.automationdirect.com/adc/shopping/catalog/drives_-a-_so
> >>ft_starters/ac_variable_frequency_drives_(vfd)/vfd_accessories/braki
> >>ng_units_-a-_resistors
> >>
> >> Looks like the cheapest one is about $30.
> >
> > I've used stovetop elements from eBay for about $12 or so.  If they
> > are good enough for
> > Haas in mass manufacture, they ought to be good enough for me.
> >
> > Jon
> >
> >
> > ___
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] Making L Type Timing pulleys.

[Chris Albertson]

I must have missed the designed size.  Yes there is a minimum size.  You
need to have a minimum number of teeth engaged.  So even if you have a 13T
pulley, if it is very close to a larger pully it would not have enough
teeth on the belt.

You CAN design a system that works if you move to different tooth size and
shape.   The specs on modern belts are better then the older L and MXL
belts so you might be able to fit hat you want into the same space as the
original.  You do a recalculation from scratch.

As to how to make the pulleys.   Just buy them.  But for testing you can 3D
print timing gear pulleys.   I make mine by  printing a plastic ring with
the teeth and then epoxying the ring to a steel pulley hub.   Fully printed
pulleys don't work well but the hybrids are nearly perfect and really easy
to make

To make a plastic ring, download the CAD file for the pulley from the
vendors web site.  I use SPD/SI and get the .step file.   Then use yu CAD
system to bore a huge hole (like 20mm or 30mm) in the pulley model.  Print
that.   Then as the printer is working turn a 20mm or 30mm hub on your
lathe and drill and tap for set screws.  What makes this a quick job is
that they provide CAD files or every pulley so you don't need to know how
to layout the teeth.



On Sat, Dec 26, 2020 at 11:57 AM andy pugh  wrote:

> On Sat, 26 Dec 2020 at 19:34, John Dammeyer 
> wrote:
>
> > Making a new lower pulley with 9 teeth is out of the question.  It's too
> small for only 9T and definitely won't fit on the 19mm motor shaft.  And
> that's the kicker.  At almost 3/4" the pulley that goes onto it has to be
> large enough to have a decent grip with set screws onto a 6mm key.
>
> I seem to recall that it is recommended to not go below 12T anyway.
>
> I don't know much about L and XL belts, all my machines have used T5.
> T5 is available in widths from 8mm to 25mm.
> https://www.bearingboys.co.uk/T5-Section-5mm-Pitch-1224-c
>
> I also have the correct hob for making custom T5 pulleys, so that is
> one reason for _me_ to use them.
>
> You could consider ignoring the keyway, especially if the motor shafts
> have a threaded hole in the end.
>
> I have several times taken inspiration from the Trantorque bushings:
> https://uk.rs-online.com/web/p/keyless-bushes/7542545/
> However they require a huge central bore, so what I have done is
> machine the pulley bore with a taper and then pull or push in a
> sleeve.
> At various times I have used a bolt in the end of the shaft, a nut
> pulling the wedge through, or a ring of bolts to push the wedge in.
>
> Here is variation on the theme, with two tapers:
> https://bodgesoc.blogspot.com/2017/01/gears.html
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1912
>
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>


-- 

Chris Albertson
Redondo Beach, California

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Re: [Emc-users] cnc lathe retrofit

[Gene Heskett]

On Saturday 26 December 2020 12:27:29 Jon Elson wrote:

> On 12/26/2020 10:47 AM, Gene Heskett wrote:
> > Two additional questions. That 70 ohm 300 watt braking
> > resistor just walked up and rang my doorbell, so are you
> > using one? and if so what settings mods have you made in
> > the VFD?
>
> Mine has several settings.  There is a minimum frequency,
> below which it goes to DC injection braking.

Thanks, the booklet doesn't actually say that. What IU m seeing now hints 
at dc braking coming in below about 50 rpm. Coasting for several seconds 
before.

> You don't want to use too much DC injection as it will cause
> an abrupt stop of the motor.  Quicker braking time will
> cause more energy to go to the resistor, if you set it too
> short, the DC link may go to overvoltage.  You may have to
> just experiment a bit to find out what decel times make
> sense on your particular machine.

What I have done, but not yet on this machine because these spindles 
aren't very amenable to being encoded, is a limit3 at the input to the 
pwmgen, no PID, and a combo of an xor to detect that the command and the 
actual dir disagree, so the present state of the dir is held in a 
sample-hold until a oneshot watching the encoder times out as the input 
to the limit3 is zeroed via a mux when the dirs disagree. Once the 
encoder times out indicating the spindle has stopped or nearly so, the 
new dir is allowed thru, the input to the limit3 is restored. and that 
re-accels the motor in the new direction.

Wash, rinse and repeat at the M4->M3 turnaround at the top of the G33.1. 
Pause 4 secs to blow the tap clean and anoint it again, repeating that 
whole sequence with an increment in the depth until the hole is tapped 
to the needed depth.

But without an encoder, I can't time any of that. I have considered a 
reflective IR lashup watching the ER-nut flats go by but how would I 
separate that for an index?  So its not been attempted to be made into a 
working, albeit very coarse encoder. But that idea works very well on 
the Sheldon, and on the GO704, but TLM's magic has been limited to taper  
tricks with g73, that quick turnaround code has not been hauled to it. I 
should, but its propensity for breaking drive parts has made me a bit 
reticent to apply this quick turnaround code there. I do have a oneshot 
watching the encoder, but its there to issue an F2 off if I leave the 
head in neutral. Easy to do since the lever is on the back of the head 
and its position isn't tallied.

> If you rigid tap, you 
> need a braking resistor to reduce the overrun after you get
> to desired depth.

Rigid tappiing also needs an encoder on the spindle, which it does not 
have. A floating tap holder maybe, but torque enough for more than a 
4-40 tap is highly problematic.

Is there an aftermarket encoder for these 24k rpm spindles?

> Jon
>
>
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Cheers, Gene Heskett
-- 
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 soap, ballot, jury, and ammo. Please use in that order."
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Re: [Emc-users] Making L Type Timing pulleys.

[andy pugh]

On Sat, 26 Dec 2020 at 19:34, John Dammeyer  wrote:

> Making a new lower pulley with 9 teeth is out of the question.  It's too 
> small for only 9T and definitely won't fit on the 19mm motor shaft.  And 
> that's the kicker.  At almost 3/4" the pulley that goes onto it has to be 
> large enough to have a decent grip with set screws onto a 6mm key.

I seem to recall that it is recommended to not go below 12T anyway.

I don't know much about L and XL belts, all my machines have used T5.
T5 is available in widths from 8mm to 25mm.
https://www.bearingboys.co.uk/T5-Section-5mm-Pitch-1224-c

I also have the correct hob for making custom T5 pulleys, so that is
one reason for _me_ to use them.

You could consider ignoring the keyway, especially if the motor shafts
have a threaded hole in the end.

I have several times taken inspiration from the Trantorque bushings:
https://uk.rs-online.com/web/p/keyless-bushes/7542545/
However they require a huge central bore, so what I have done is
machine the pulley bore with a taper and then pull or push in a
sleeve.
At various times I have used a bolt in the end of the shaft, a nut
pulling the wedge through, or a ring of bolts to push the wedge in.

Here is variation on the theme, with two tapers:
https://bodgesoc.blogspot.com/2017/01/gears.html

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1912


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Re: [Emc-users] Making L Type Timing pulleys.

[Chris Albertson]

My source for buying belts and pulleys is SPD/SI.   On their web site is
some tables that will allow you to select the proper size belt.
https://sdp-si.com/resources/


Here is a good on-line length calculator.
Length: https://www.bbman.com/belt-length-calculator/

One more thing:  If you are going to replace the belts and one pulley why
not replace BOTH pulleys and move to a more modern tooth profile?   The
newer GT2 profile will be stronger, have near zero-backlash, and is
quieter. In general, the newer rounded profile is better than those
square profiles.

On Sat, Dec 26, 2020 at 11:34 AM John Dammeyer 
wrote:

> Hi everyone,
> As I mentioned in a previous posting I'm expecting a Bergerda AC Servo to
> replace the Stepper motor on the knee of my mill.
> http://www.autoartisans.com/mill/KneeDrive.jpg
>
> The photo shows how the stepper is connected.  The L type pulleys were a
> gift from a friend who salvaged them from some equipment.  The ratio is 3:1
> with the smaller pulley having an insert for the 1/2" shaft on the stepper
> motor.  With 3:1 the 7NM motor can work up to 300 RPM before the torque
> falls below about 3.5NM and it stalls.  That 3:1 reduction puts 100 RPM
> works out to 25ipm.
>
> The 80SM-M0320MAL I've ordered will handle the 3.5NM all the way to the
> 2000 RPM max speed will give 166 ipm which is probably way more than the
> vertical ACME screw can handle on a regular basis but I'll be more likely
> to do a quick move to a tool change position than right now where it
> appears to take forever to get out of the way.
> http://www.autoartisans.com/mill/80SeriesACServoMotor.pdf
>
> I'm right on the edge though.  I'd like to change to 4:1.  Currently the
> upper pulley at 36T, as shown in the photo, is slid onto the 25mm shaft and
> anchored onto the square handle drive part.  The lower pulley at 12T has a
> steel insert with a single set screw on the stepper motor 1/2" flat.
>
> Making a new lower pulley with 9 teeth is out of the question.  It's too
> small for only 9T and definitely won't fit on the 19mm motor shaft.  And
> that's the kicker.  At almost 3/4" the pulley that goes onto it has to be
> large enough to have a decent grip with set screws onto a 6mm key.
>
> And so here's the problem.  A large enough pulley from say Misumi, in L
> Type, makes for too many teeth to get 4:1 without a huge driven pulley.
> I've been using the various pulley calculators and I can't seem to come up
> with a different belt size that will work.
>
> My thinking is as follows:
> 1. A 4:1 ratio implies driven pulley is 4x the diameter of driving pulley
> 2. A driven pulley of 6" diameter means 1.5" max for the driving pulley or
> a Pd of 38mm driving 152mm Pd.
> 3. 38mm - 19mm shaft diameter leaves 19mm or a hub thickness of 9.5mm.
> 4. Minus half the key width of 3mm I'm left with 6.5mm set screw length.
> That's  enough right?
> 5. Circumference of 38mm Pd pulley is about 119mm.
> 6. Using an XL size belt with a pitch of 5.08mm suggests about 24 Teeth
> and a Pd of 38.8mm.
> 7. So I need 96 teeth or circumference of 487.68 gives 155.23mm diameter
> (6.11") which is just at the max size.
>
> Will an XL series 9.5mm wide belt be strong enough turning a 24T 39mm
> pulley at 2000 RPM which drives a 96T 155mm pulley at 500 RPM?
>
> Do I have enough 'meat' on the driving pulley?
>
> Is there a better more appropriate belt style?
>
> Thanks
> John Dammeyer
>
>
> "ELS! Nothing else works as well for your Lathe"
> Automation Artisans Inc.
> www dot autoartisans dot com
>
>
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>


-- 

Chris Albertson
Redondo Beach, California

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[Emc-users] Making L Type Timing pulleys.

[John Dammeyer]

Hi everyone,
As I mentioned in a previous posting I'm expecting a Bergerda AC Servo to 
replace the Stepper motor on the knee of my mill.
http://www.autoartisans.com/mill/KneeDrive.jpg
 
The photo shows how the stepper is connected.  The L type pulleys were a gift 
from a friend who salvaged them from some equipment.  The ratio is 3:1 with the 
smaller pulley having an insert for the 1/2" shaft on the stepper motor.  With 
3:1 the 7NM motor can work up to 300 RPM before the torque falls below about 
3.5NM and it stalls.  That 3:1 reduction puts 100 RPM works out to 25ipm.  
 
The 80SM-M0320MAL I've ordered will handle the 3.5NM all the way to the 2000 
RPM max speed will give 166 ipm which is probably way more than the vertical 
ACME screw can handle on a regular basis but I'll be more likely to do a quick 
move to a tool change position than right now where it appears to take forever 
to get out of the way.
http://www.autoartisans.com/mill/80SeriesACServoMotor.pdf
 
I'm right on the edge though.  I'd like to change to 4:1.  Currently the upper 
pulley at 36T, as shown in the photo, is slid onto the 25mm shaft and anchored 
onto the square handle drive part.  The lower pulley at 12T has a steel insert 
with a single set screw on the stepper motor 1/2" flat.
 
Making a new lower pulley with 9 teeth is out of the question.  It's too small 
for only 9T and definitely won't fit on the 19mm motor shaft.  And that's the 
kicker.  At almost 3/4" the pulley that goes onto it has to be large enough to 
have a decent grip with set screws onto a 6mm key.  
 
And so here's the problem.  A large enough pulley from say Misumi, in L Type, 
makes for too many teeth to get 4:1 without a huge driven pulley.  I've been 
using the various pulley calculators and I can't seem to come up with a 
different belt size that will work.
 
My thinking is as follows:  
1. A 4:1 ratio implies driven pulley is 4x the diameter of driving pulley
2. A driven pulley of 6" diameter means 1.5" max for the driving pulley or a Pd 
of 38mm driving 152mm Pd.
3. 38mm - 19mm shaft diameter leaves 19mm or a hub thickness of 9.5mm. 
4. Minus half the key width of 3mm I'm left with 6.5mm set screw length.  
That's  enough right?
5. Circumference of 38mm Pd pulley is about 119mm.
6. Using an XL size belt with a pitch of 5.08mm suggests about 24 Teeth and a 
Pd of 38.8mm.
7. So I need 96 teeth or circumference of 487.68 gives 155.23mm diameter 
(6.11") which is just at the max size.
 
Will an XL series 9.5mm wide belt be strong enough turning a 24T 39mm pulley at 
2000 RPM which drives a 96T 155mm pulley at 500 RPM?
 
Do I have enough 'meat' on the driving pulley?  
 
Is there a better more appropriate belt style?
 
Thanks
John Dammeyer
 
 
"ELS! Nothing else works as well for your Lathe"
Automation Artisans Inc.
www dot autoartisans dot com 
 

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Re: [Emc-users] Chinese VFDs with good reputations

[Jon Elson]

On 12/26/2020 11:44 AM, Dave Cole wrote:
What low cost Chinese drives have you guys used with great 
success?


I have a Magnetek (made by Yaskawa) GPD333 on my Bridgeport 
mill.  I think it is designed for single-phase operation.  
It is a 1 HP drive on a 21 HP motor, so not derated.  I do 
put a fan on it for

rigid tapping.

I have an 11 KW Hitachi drive on my Sheldon 15" lathe.  It 
is NOT rated for single-phase, but works fine.


Jon


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Re: [Emc-users] Chinese VFDs with good reputations

[John Dammeyer]

I looked at prices for a 2HP 3phase and a VFD (like Hitatchi Vectorless?) and 
found without shipping the price was approaching $600.  For less than that I 
ended up with Bergerda.

I'm using a Bergerda AC Servo 110SM series (1.8kW, 6NM)  on my spindle, 
currently with a cheap PWM module until I wire up a second BoB for step/dir 
control.  With PWM I get 100RPM to 3000RPM without a belt change.  With stepper 
I can have it move very very slowly.

I also swapped in, for testing, a smaller 60SM series 1.27NM Bergerda onto the 
X axis.  Once I read the manual correctly I got step and direction working 
well.  The drive isn't overly large but is a bit bigger than the HP_UHU which 
runs the brushed servo motors also 1.2 NM. 
This video shows it now working.  I can get 180ipm on the X axis just like the 
much bigger DC Servo.
https://youtu.be/43liAVILgHY

The Gecko Stepper G213V driver on the knee has now failed for the second time 
melting the connector again.  Absolutely no response from Gecko so it's being 
scrapped and FedEx tracking says my new Bergerda AC 80SM series servo (3.5NM) 
will arrive on Wednesday along with 2 more of the small 60SM units.

They aren't cheap compared to stepper motors.  In my case I get to remove a 
complete Toroidal power supply that runs only the stepper but is big enough for 
the entire mill with 60VDC motor drivers.

The DC Servos and Harmonic drive (controlled with STMBL) run on a 105DC 
Toroidal power supply.  I could remove this and run the Harmonic off 110VAC to 
DC with a smaller isolation transformer.  Then I'd have room for the Bergerda 
drives.
This is the MACH3 Road Runner with the much bigger DC Servos and the 1200 oz-in 
(drops to 3.5NM at 300RPM) on the knee.
https://youtu.be/OUQzyp-3WXY

I've found support and price excellent, shipping horrendous.   For example I 
found that when the spindle stopped it would sometimes sit with a bit of a 
squeal.  A quick email to Bergerda and discussion and we figured out which 
parameters to tweak.  Now it's dead quiet.  And much smaller than the single 
phase 1.5kW 2HP motor.
http://www.autoartisans.com/mill/NewPulleys-1.jpg

John Dammeyer

> -Original Message-
> From: Dave Cole [mailto:linuxcncro...@gmail.com]
> Sent: December-26-20 9:44 AM
> To: emc-users@lists.sourceforge.net
> Subject: [Emc-users] Chinese VFDs with good reputations
> 
> What low cost Chinese drives have you guys used with great success?
> 
> I'm talking mostly single phase input drives.
> 
> There are a lot of look a likes on Ebay.�� Some are dirt cheap. Others
> not so much.
> 
> Some specify that they are specifically for water cooled spindles, etc.
> 
> Others say almost nothing.
> 
> Dave
> 
> 
> 
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Re: [Emc-users] cnc lathe retrofit

[andy pugh]

On Sat, 26 Dec 2020 at 16:49, Gene Heskett  wrote:

> Two additional questions. That 70 ohm 300 watt braking resistor just
> walked up and rang my doorbell, so are you using one?

I am not using one. It would be useful if I was, since I added
on-the-fly gearshifting to the two speed box.

The idea is that if it is in low gear and the spindle speed goes above
500 rpm then it disconnects the low-speed clutch and slows the motor
down to the right speed to operate the high-speed clutch.
Unfortunately the spindle slows faster than the motor, so they only
really catch each other at zero-zero.

If I had a braking resistor then I could slow the motor faster, and
there would be more chance of catching the gear change.

But the VFD is next to the motor, behind a panel that is only
accessible once the lathe is pulled away from the wall.
So I have not tried to add one.

Downshifting goes a little better.

I drive an old fire engine that has the same problem, if you are going
up a steep hill, that the vehicle could climb in top or third gear, if
you have to stop and go into first, there is no way to get out of
first and you have to hold it to the top of the hill.


--
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1912


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[Emc-users] Chinese VFDs with good reputations

[Dave Cole]

What low cost Chinese drives have you guys used with great success?

I'm talking mostly single phase input drives.

There are a lot of look a likes on Ebay.   Some are dirt cheap. Others 
not so much.


Some specify that they are specifically for water cooled spindles, etc.

Others say almost nothing.

Dave



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Re: [Emc-users] Checking vfd hookup question?

[Dave Cole]

I'm sure those could be made to work if they are of an acceptable Ohms 
range, but how do you mount them?

They are just elements.
Most braking resistors on larger machines are in cages on the top or 
side of the control panels.
For small drives, they are oftentimes just screwed to the panel 
backplane,   But then they don't get that hot.


By the time you fab the cage, you can almost buy one new with a cage and 
that is rated.


Dave

On 12/24/2020 1:36 PM, Jon Elson wrote:

On 12/24/2020 11:43 AM, Dave Cole wrote:

Automation Direct sells braking resistors.
https://www.automationdirect.com/adc/shopping/catalog/drives_-a-_soft_starters/ac_variable_frequency_drives_(vfd)/vfd_accessories/braking_units_-a-_resistors 


Looks like the cheapest one is about $30.
I've used stovetop elements from eBay for about $12 or so.  If they 
are good enough for

Haas in mass manufacture, they ought to be good enough for me.

Jon


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Re: [Emc-users] cnc lathe retrofit

[Jon Elson]

On 12/26/2020 10:47 AM, Gene Heskett wrote:
Two additional questions. That 70 ohm 300 watt braking 
resistor just walked up and rang my doorbell, so are you 
using one? and if so what settings mods have you made in 
the VFD?
Mine has several settings.  There is a minimum frequency, 
below which it goes to DC injection braking.
You don't want to use too much DC injection as it will cause 
an abrupt stop of the motor.  Quicker braking time will 
cause more energy to go to the resistor, if you set it too 
short, the DC link may go to overvoltage.  You may have to 
just experiment a bit to find out what decel times make 
sense on your particular machine.  If you rigid tap, you 
need a braking resistor to reduce the overrun after you get 
to desired depth.


Jon


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Re: [Emc-users] cnc lathe retrofit

[Gene Heskett]

On Saturday 26 December 2020 11:23:20 Gene Heskett wrote:

> On Saturday 26 December 2020 10:08:47 andy pugh wrote:

[...]

> I think we are on about the same page, just need to find the round
> tuit.

Two additional questions. That 70 ohm 300 watt braking resistor just 
walked up and rang my doorbell, so are you using one? and if so what 
settings mods have you made in the VFD?

Thanks Andy.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] cnc lathe retrofit

[Gene Heskett]

On Saturday 26 December 2020 10:08:47 andy pugh wrote:

> On Sat, 26 Dec 2020 at 10:00, andrew beck  
wrote:
> > also what do people do for E stop circuits with analog systems? I
> > have only used a  step direction system before this
>
> On my lathe the main servo power supply comes via a contactor with a
> 24V coil, and that coil power passes through two e-stop switches.
>
> LinuxCNC controls the 24V contactor coil, but the e-stop switches in
> series in that circuit can over-ride.
> I couldn't  remember if the contactor was controlled via an ssr, or
> whether it's directly from a 7i84 output. So I found this photo:
> https://photos.app.goo.gl/7VSURFqEFVq9s3bk8 which suggests an SSR for
> the main relay.

Same here, I have a pile of the hoymc(sp?) 40 amp 600 volt SSR's in such 
circuits already. In fact since my field power is 12 volts, that enough 
to fire 2 of them in series, so one 7i76D output controls both sides of 
the 250volt to the new vfd on the 6040.  I can see the reflection of the 
lit leds thru a small hole in the box cover. Adding a contact from a 
relay in series with that signal would be easily done.  But I'm not done 
yet.

The mister draws enough air it keeps a bigger 125 psi 2hp compressor 
moderately busy, and HOT, so since it does not need that much air 
pressure, I've bought one of those car tire compressors but with a 120 
volt motor, so it will grow a relay to turn it on with the misters pump 
circuit. With timers running it, it outputs about 1/4 drop of liquid 5 
to 20 times a second, not enough to flood the work but does keep the 
tool wet.

But its a lot noisier than I expected and not muffle-able as it has no 
identifiable intake port, so I'll have to put it in a noise containing 
box yet to be made. Suspended on bike tire innertube straps I think.

As is from the bigger compressor, it keeps a 1/8" tool wet with kool-mist 
and clean enough I have cut out the motor mounts for the BS-1 from 1/2" 
alu with one tool, at 14k revs for a total cut length of nearly a meter, 
leaving a beautiful finish. Feed depth increments cannot be seen in the 
finished cut, moving half a mm deep a pass at 250mm feeds. This will, at 
virtually no head pressure, supply enough air to sweep away some of the 
alu mud the existing setup doesn't.  And so far has used less than half 
an 8 oz coke bottle of kool-mist mix.

> There is a wire back from the 24V coil terminals to a 7i84 input. That
> is used to inform LinuxCNC if the e-stops are activated, triggering
> the software e-stop and turning the machine off.

> I seem to recall making sure that there was a protection diode, so
> that the voltage as the coil turned off didn't damage the 7i84 input

I forgot to put one in on one of my relay circuits and I have a 7i76D 
port that may stick on, but hasn't since I installed the diode. Dumb old 
man...

> pin.
>
> So, e-stop drops out the contactor, the drives turn off, LinuxCNC
> spots that the coil is de-energised and e-stops itself to match.

I think we are on about the same page, just need to find the round tuit. 

Thanks Andy.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
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Re: [Emc-users] cnc lathe retrofit

[andy pugh]

On Sat, 26 Dec 2020 at 10:00, andrew beck  wrote:

> also what do people do for E stop circuits with analog systems? I have only
> used a  step direction system before this

On my lathe the main servo power supply comes via a contactor with a
24V coil, and that coil power passes through two e-stop switches.

LinuxCNC controls the 24V contactor coil, but the e-stop switches in
series in that circuit can over-ride.
I couldn't  remember if the contactor was controlled via an ssr, or
whether it's directly from a 7i84 output. So I found this photo:
https://photos.app.goo.gl/7VSURFqEFVq9s3bk8 which suggests an SSR for
the main relay.

There is a wire back from the 24V coil terminals to a 7i84 input. That
is used to inform LinuxCNC if the e-stops are activated, triggering
the software e-stop and turning the machine off.
I seem to recall making sure that there was a protection diode, so
that the voltage as the coil turned off didn't damage the 7i84 input
pin.

So, e-stop drops out the contactor, the drives turn off, LinuxCNC
spots that the coil is de-energised and e-stops itself to match.

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1912


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Re: [Emc-users] cnc lathe retrofit

[Gene Heskett]

On Saturday 26 December 2020 04:57:38 andrew beck wrote:

> hey everyone
>
> just for your interest here is a cnc lathe I am retrofitting here in
> NZ
>
> link to video on youtube 
>
> still got a whole lot of work and need to sort out analog servo drive
> stuff tomorrow but thought I would send a email anyway
>
> also what do people do for E stop circuits with analog systems? I have
> only used a  step direction system before this
>
> the servo drive has a "servo on input)  that allows power to motor.  I
> think the enable input from 7i77 should trigger this on and off.  I
> want my big estop to also cut power too though so that I am not
> relying on software as that is not safe.  current plan is to just put
> a relay in the servo enable circuit from 7i77 to servo drive.  which
> gets cut by the Estop switch circuit.  seems simple enough
>
> would love any ideas though
>
> and any things to watch out for.
>
> I know about checking encoder direction first and leaving motors on
> bench at first and all that sort of stuff.  I will just take it easy
>
> regards

Wow, Andrew.  That is a lot more machine than anything I've got. And 
separate e-stop circuits are something that I have been lacking in 
doing. I have tended to make all that stuff as slaves to the motion 
enable signal, controlled by the F2 key on the keyboard, which in turn 
controls all other machine power, and has worked flawlessly. But it is 
not a guard against a computer crash which really needs an independent 
way to shut down the power. I've considered a multipole relay which 
would be in series with the enable signal, which could shut off all 
power to the machine independent of the computer, and I bought several 
of the latching switches from the mini-lathe parts list, but haven't 
found that famous round tuit yet. But I think that idea has the best 
merit, bypassing, and over-riding anything the computer might decide to 
make the machine do.

I did change the motors and drives on my Sheldon this fall, from normal 
steppers to the newer 3 phase stepper/servo's and I am very happy with 
the results of feeding the FAULT signals back into LinuxCNC, effectively 
toggling the F2 button there. I traded a 1600 oz/in nema 34 on the z 
screw for a 3NM nema-23, as much because the 1600 shook tools off the 
whole machine, doubling my Z speed rapids, and pulled a 270 oz/in 
nema-23 off the X in favor of a 2NM version of the 3 phase drive. The 
whole machine now can move 2-3x faster, and moves like casper the ghost.

I haven't tested the X because the screw is so small and I might damage 
it with the 2NM motor geared 2/1, but I can now mount a carbide tool, 
position it to hit a chuck jaw, and drive it into the chuck jaw at 2 
ipm, from the Z, it detects the contact and faults, with the Z bouncing 
back from jaw contact by about .010" as the power goes off, without 
damage to the chuck jaw or to the carbide chip in the tool. With a 25mm 
Z screw, that 1600 would have crushed the chip and bent the tool if it 
were pinned to the carriage, which it is not.

That to me was worth the nominally $250 to swap the motors. And although 
I've been warned that some have noted the stepper servos can lose 
counts, the 3 phase drives I have used so far haven't lost a step. I'd 
submit that those reporting such as problem have noise in their systems 
or are pushing the step timing.

Anyway, that's my take on it, but if anyone has a good pattern to make 
round tuits that isn't already copyrighted, I'll make some for my 
friends as several have lamented they haven't found one yet.

That would be a piece of cake for my 6040 with its new 2.2kw spindle.

Now, lets all hope that 2021 will be a better year, 2020 was/is the pits.

> Andrew
>
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Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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[Emc-users] cnc lathe retrofit

[andrew beck]

hey everyone

just for your interest here is a cnc lathe I am retrofitting here in NZ

link to video on youtube 

still got a whole lot of work and need to sort out analog servo drive stuff
tomorrow but thought I would send a email anyway

also what do people do for E stop circuits with analog systems? I have only
used a  step direction system before this

the servo drive has a "servo on input)  that allows power to motor.  I
think the enable input from 7i77 should trigger this on and off.  I want my
big estop to also cut power too though so that I am not relying on software
as that is not safe.  current plan is to just put a relay in the servo
enable circuit from 7i77 to servo drive.  which gets cut by the Estop
switch circuit.  seems simple enough

would love any ideas though

and any things to watch out for.

I know about checking encoder direction first and leaving motors on bench
at first and all that sort of stuff.  I will just take it easy

regards

Andrew

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