Re: [Emc-users] Spindle positioning.

[andy pugh]

On Tue, 23 Nov 2021 at 01:05, John Dammeyer  wrote:

>   Likely why the set screw works loose after a number of cycles.

I am surprised that the air wrench doesn't have the usual ball-detente
to retain the socket.

-- 
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

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

And therein lies the problem.  For your NMBT-30 quick change tooling you could 
just as easily set up wave washers and just press and release the draw bar as 
is done on so many of those instead of turning into the holder itself.  But it 
only requires one or two turns before that large cone is no longer held by 
friction.

Contrast that with .75" or so of the top of the R8 which is a sliding fit with 
supposedly 0.001" difference in diameter.  That requires a substantial push to 
release it compared with the NMBT-30 or TTS that require a push of 0.050" or so.

BTW, for fun I installed the 1/4" TTS held chuck and then manually brought the 
drawbar down with the air cyl.  Then spun the spindle up to 700 RPM on the AXIS 
display. Some LCNC content here...  8-).The airmotor in the wrench, 
although not lubricated with oily air at this point, spun without any issues.  
However it was visibly clear that the draw bar nut wasn't completely centered 
as the bottom of the socket wobbled ever so slightly, and at the top there was 
also ticking noise from the 3/8" socket connection since it wasn't spinning 
concentric with the impact wrench spindle.  Likely why the set screw works 
loose after a number of cycles.

 John



> From: John Figie [mailto:zephyr9...@gmail.com]
> Maybe I didn't fully answer your question. After the tool drops out. If the
> button is held the impact driver will just keep spinning like an unloaded
> impact wrench.
> 
> John
> 
> On Mon, Nov 22, 2021, 5:57 PM John Figie  wrote:
> 
> > When the load or unload button is pressed the impact driver first moves
> > down and then starts impacting for as long as the button is pressed. I only
> > let it impact for about 1 or 2 seconds.
> >
> > On Mon, Nov 22, 2021, 5:39 PM John Dammeyer 
> > wrote:
> >
> >> So far I'm well under the $974 of the R8 version although if I had to pay
> >> retail for the GIM controller I'm using then I'd be well over that.  So far
> >> I think I'm at about $200 Cdn.  plus I'm using one of the first prototype
> >> GIMs I build almost 10 years ago.
> >>
> >> https://www.kurtworkholding.com/product/kurt-bridgeport-series-i-std-2-j/
> >>
> >> What happens with yours if you pressed the unload button for 5 seconds?
> >> Obviously the tool would drop out.  But does anything else unscrew or
> >> require manual operations to put back?
> >>
> >>
> >> > -Original Message-
> >> > From: John Figie [mailto:zephyr9...@gmail.com]
> >> > Sent: November-22-21 2:30 PM
> >> > To: Enhanced Machine Controller (EMC)
> >> > Subject: Re: [Emc-users] Spindle positioning.
> >> >
> >> > Instead of a drawbar with a hex end you could use the kind with a spline
> >> > end like the ones that Kurt sells for their power drawbar. My Bridgeport
> >> > came with a Kurt power drawbar. I have had it since around 2003. Still
> >> > using the same drawbar. The socket looks kind of like a torx socket -
> >> maybe
> >> > it is - I never looked at it that close. The Kurt uses butterfly impact
> >> > kind of like yours. It just uses regulated air pressure. I just let it
> >> > drive the drawbar for about 1 or 2 seconds. It has never stripped and I
> >> > have never replaced the drawbar.  Tooling is NMTB 30. Home shop use
> >> only.
> >> >
> >> > http://www.machineability.com/Bridgeport_series_II.html
> >> >
> >> > John
> >> >
> >> >
> >> > On Mon, Nov 22, 2021, 3:39 PM John Dammeyer 
> >> wrote:
> >> >
> >> > > Hi Mathew,
> >> > > I want to be able to swap easily and quickly between R8 and TTS.
> >> Here's a
> >> > > selection of some of the tooling.
> >> > >
> >> > > http://www.autoartisans.com/mill/ToolSelection.jpg
> >> > >
> >> > >  There's a full set of R8 collets of course.  The spring loaded Tap
> >> Holder
> >> > > has a 3/4" shank so it really just needs a TTS collar to make it full
> >> TTS.
> >> > >   The two gear cutter arbours for the different sized cutters.  Face
> >> mill.
> >> > > Changing from a 1/4" drill bit means I have to swap out the TTS to
> >> install
> >> > > the R8 based expensive 16mm JT3 ball bearing chuck.
> >> > >
> >> > > To change completely over to TTS is expensive.  To change to a mill
> >> with a
> >> > > NMBT or CAT cone type is really expensive.   The lowest cost power
> >> toolbar
> >> > > system was the butterfly wrench and air cylinder.  Cost escalated as
> >> the
> >> > > ordered electric pneumatic valves just never showed up from China so
> >> I went
> >> > > local.  Not really expensive but it adds up as do all the fittings.
> >> > >
> >> > > At this point I could see spending as much as $150 Cdn. for the
> >> planetary
> >> > > gear and stepper combination.Still way less expensive than fully
> >> > > switching over to TTS which I probably will over time but not all in
> >> one
> >> > > shot.   And I'm not sure the TTS wouldn't slip with the 5/8" chuck
> >> holding
> >> > > a 1" reduced shank drill bit.
> >> > >
> >> > > First step now is to wait for the 12 point deep socket.
> >> > >
> >> > > John
> >> > >

Re: [Emc-users] Spindle positioning.

[John Figie]

Maybe I didn't fully answer your question. After the tool drops out. If the
button is held the impact driver will just keep spinning like an unloaded
impact wrench.

John

On Mon, Nov 22, 2021, 5:57 PM John Figie  wrote:

> When the load or unload button is pressed the impact driver first moves
> down and then starts impacting for as long as the button is pressed. I only
> let it impact for about 1 or 2 seconds.
>
> On Mon, Nov 22, 2021, 5:39 PM John Dammeyer 
> wrote:
>
>> So far I'm well under the $974 of the R8 version although if I had to pay
>> retail for the GIM controller I'm using then I'd be well over that.  So far
>> I think I'm at about $200 Cdn.  plus I'm using one of the first prototype
>> GIMs I build almost 10 years ago.
>>
>> https://www.kurtworkholding.com/product/kurt-bridgeport-series-i-std-2-j/
>>
>> What happens with yours if you pressed the unload button for 5 seconds?
>> Obviously the tool would drop out.  But does anything else unscrew or
>> require manual operations to put back?
>>
>>
>> > -Original Message-
>> > From: John Figie [mailto:zephyr9...@gmail.com]
>> > Sent: November-22-21 2:30 PM
>> > To: Enhanced Machine Controller (EMC)
>> > Subject: Re: [Emc-users] Spindle positioning.
>> >
>> > Instead of a drawbar with a hex end you could use the kind with a spline
>> > end like the ones that Kurt sells for their power drawbar. My Bridgeport
>> > came with a Kurt power drawbar. I have had it since around 2003. Still
>> > using the same drawbar. The socket looks kind of like a torx socket -
>> maybe
>> > it is - I never looked at it that close. The Kurt uses butterfly impact
>> > kind of like yours. It just uses regulated air pressure. I just let it
>> > drive the drawbar for about 1 or 2 seconds. It has never stripped and I
>> > have never replaced the drawbar.  Tooling is NMTB 30. Home shop use
>> only.
>> >
>> > http://www.machineability.com/Bridgeport_series_II.html
>> >
>> > John
>> >
>> >
>> > On Mon, Nov 22, 2021, 3:39 PM John Dammeyer 
>> wrote:
>> >
>> > > Hi Mathew,
>> > > I want to be able to swap easily and quickly between R8 and TTS.
>> Here's a
>> > > selection of some of the tooling.
>> > >
>> > > http://www.autoartisans.com/mill/ToolSelection.jpg
>> > >
>> > >  There's a full set of R8 collets of course.  The spring loaded Tap
>> Holder
>> > > has a 3/4" shank so it really just needs a TTS collar to make it full
>> TTS.
>> > >   The two gear cutter arbours for the different sized cutters.  Face
>> mill.
>> > > Changing from a 1/4" drill bit means I have to swap out the TTS to
>> install
>> > > the R8 based expensive 16mm JT3 ball bearing chuck.
>> > >
>> > > To change completely over to TTS is expensive.  To change to a mill
>> with a
>> > > NMBT or CAT cone type is really expensive.   The lowest cost power
>> toolbar
>> > > system was the butterfly wrench and air cylinder.  Cost escalated as
>> the
>> > > ordered electric pneumatic valves just never showed up from China so
>> I went
>> > > local.  Not really expensive but it adds up as do all the fittings.
>> > >
>> > > At this point I could see spending as much as $150 Cdn. for the
>> planetary
>> > > gear and stepper combination.Still way less expensive than fully
>> > > switching over to TTS which I probably will over time but not all in
>> one
>> > > shot.   And I'm not sure the TTS wouldn't slip with the 5/8" chuck
>> holding
>> > > a 1" reduced shank drill bit.
>> > >
>> > > First step now is to wait for the 12 point deep socket.
>> > >
>> > > John
>> > >
>> > >
>> > > > -Original Message-
>> > > > From: Matthew Herd [mailto:herd.m...@gmail.com]
>> > > > Sent: November-22-21 10:49 AM
>> > > > To: Enhanced Machine Controller (EMC)
>> > > > Subject: Re: [Emc-users] Spindle positioning.
>> > > >
>> > > > Hi John,
>> > > >
>> > > > You don?t need pull studs on the R-8 collets, just thread the draw
>> bar
>> > > into the collet. Either until it stops or loctite the draw bar at
>> > > > the right depth. Then use a Belleville washer and air cylinder setup
>> > > like Andy?s.
>> > > >
>> > > > Matt
>> > > >
>> > > > > On Nov 22, 2021, at 1:32 PM, John Dammeyer <
>> jo...@autoartisans.com>
>> > > wrote:
>> > > > >
>> > > > > ?It's the lowering of the wrench that I don't have a lot of
>> control
>> > > on.  It's pushed down hard enough to keep the draw bar on top of
>> > > > the spindle so as it turns it pushes the sometimes a bit stiff R8
>> all
>> > > the way down and out.  If it's allow to move upwards (or I haven't
>> > > > locked the quill) then the drawbar may unthread but I then have to
>> push
>> > > on the draw bar.
>> > > > >
>> > > > > A sensor on the Z down may be what has to happen.  Then repeated
>> tries
>> > > with blipping the air wrench until it goes down all the
>> > > > way is an option.
>> > > > >
>> > > > > Making a draw bar from oil hardening steel and hardening the head
>> a
>> > > bit so it doesn't get carved away and ends up more slippery
>> > > > might also be a 

Re: [Emc-users] Spindle positioning.

[John Figie]

When the load or unload button is pressed the impact driver first moves
down and then starts impacting for as long as the button is pressed. I only
let it impact for about 1 or 2 seconds.

On Mon, Nov 22, 2021, 5:39 PM John Dammeyer  wrote:

> So far I'm well under the $974 of the R8 version although if I had to pay
> retail for the GIM controller I'm using then I'd be well over that.  So far
> I think I'm at about $200 Cdn.  plus I'm using one of the first prototype
> GIMs I build almost 10 years ago.
>
> https://www.kurtworkholding.com/product/kurt-bridgeport-series-i-std-2-j/
>
> What happens with yours if you pressed the unload button for 5 seconds?
> Obviously the tool would drop out.  But does anything else unscrew or
> require manual operations to put back?
>
>
> > -Original Message-
> > From: John Figie [mailto:zephyr9...@gmail.com]
> > Sent: November-22-21 2:30 PM
> > To: Enhanced Machine Controller (EMC)
> > Subject: Re: [Emc-users] Spindle positioning.
> >
> > Instead of a drawbar with a hex end you could use the kind with a spline
> > end like the ones that Kurt sells for their power drawbar. My Bridgeport
> > came with a Kurt power drawbar. I have had it since around 2003. Still
> > using the same drawbar. The socket looks kind of like a torx socket -
> maybe
> > it is - I never looked at it that close. The Kurt uses butterfly impact
> > kind of like yours. It just uses regulated air pressure. I just let it
> > drive the drawbar for about 1 or 2 seconds. It has never stripped and I
> > have never replaced the drawbar.  Tooling is NMTB 30. Home shop use only.
> >
> > http://www.machineability.com/Bridgeport_series_II.html
> >
> > John
> >
> >
> > On Mon, Nov 22, 2021, 3:39 PM John Dammeyer 
> wrote:
> >
> > > Hi Mathew,
> > > I want to be able to swap easily and quickly between R8 and TTS.
> Here's a
> > > selection of some of the tooling.
> > >
> > > http://www.autoartisans.com/mill/ToolSelection.jpg
> > >
> > >  There's a full set of R8 collets of course.  The spring loaded Tap
> Holder
> > > has a 3/4" shank so it really just needs a TTS collar to make it full
> TTS.
> > >   The two gear cutter arbours for the different sized cutters.  Face
> mill.
> > > Changing from a 1/4" drill bit means I have to swap out the TTS to
> install
> > > the R8 based expensive 16mm JT3 ball bearing chuck.
> > >
> > > To change completely over to TTS is expensive.  To change to a mill
> with a
> > > NMBT or CAT cone type is really expensive.   The lowest cost power
> toolbar
> > > system was the butterfly wrench and air cylinder.  Cost escalated as
> the
> > > ordered electric pneumatic valves just never showed up from China so I
> went
> > > local.  Not really expensive but it adds up as do all the fittings.
> > >
> > > At this point I could see spending as much as $150 Cdn. for the
> planetary
> > > gear and stepper combination.Still way less expensive than fully
> > > switching over to TTS which I probably will over time but not all in
> one
> > > shot.   And I'm not sure the TTS wouldn't slip with the 5/8" chuck
> holding
> > > a 1" reduced shank drill bit.
> > >
> > > First step now is to wait for the 12 point deep socket.
> > >
> > > John
> > >
> > >
> > > > -Original Message-
> > > > From: Matthew Herd [mailto:herd.m...@gmail.com]
> > > > Sent: November-22-21 10:49 AM
> > > > To: Enhanced Machine Controller (EMC)
> > > > Subject: Re: [Emc-users] Spindle positioning.
> > > >
> > > > Hi John,
> > > >
> > > > You don?t need pull studs on the R-8 collets, just thread the draw
> bar
> > > into the collet. Either until it stops or loctite the draw bar at
> > > > the right depth. Then use a Belleville washer and air cylinder setup
> > > like Andy?s.
> > > >
> > > > Matt
> > > >
> > > > > On Nov 22, 2021, at 1:32 PM, John Dammeyer  >
> > > wrote:
> > > > >
> > > > > ?It's the lowering of the wrench that I don't have a lot of control
> > > on.  It's pushed down hard enough to keep the draw bar on top of
> > > > the spindle so as it turns it pushes the sometimes a bit stiff R8 all
> > > the way down and out.  If it's allow to move upwards (or I haven't
> > > > locked the quill) then the drawbar may unthread but I then have to
> push
> > > on the draw bar.
> > > > >
> > > > > A sensor on the Z down may be what has to happen.  Then repeated
> tries
> > > with blipping the air wrench until it goes down all the
> > > > way is an option.
> > > > >
> > > > > Making a draw bar from oil hardening steel and hardening the head a
> > > bit so it doesn't get carved away and ends up more slippery
> > > > might also be a requirement.
> > > > >
> > > > > John
> > > > >
> > > > >
> > > > >> -Original Message-
> > > > >> From: andy pugh [mailto:bodge...@gmail.com]
> > > > >> Sent: November-22-21 5:41 AM
> > > > >> To: Enhanced Machine Controller (EMC)
> > > > >> Subject: Re: [Emc-users] Spindle positioning.
> > > > >>
> > > > >>> On Mon, 22 Nov 2021 at 08:03, John Dammeyer <
> jo...@autoartisans.com>
> 

Re: [Emc-users] Spindle positioning.

[Gene Heskett]

On Monday 22 November 2021 17:30:08 John Figie wrote:

> Instead of a drawbar with a hex end you could use the kind with a
> spline end like the ones that Kurt sells for their power drawbar. My
> Bridgeport came with a Kurt power drawbar. I have had it since around
> 2003. Still using the same drawbar. The socket looks kind of like a
> torx socket - maybe it is - I never looked at it that close. The Kurt
> uses butterfly impact kind of like yours. It just uses regulated air
> pressure. I just let it drive the drawbar for about 1 or 2 seconds. It
> has never stripped and I have never replaced the drawbar.  Tooling is
> NMTB 30. Home shop use only.
>
> http://www.machineability.com/Bridgeport_series_II.html
>
> John
>
Sweet machine John, wish I had room for one like 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, 1940)
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

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

So far I'm well under the $974 of the R8 version although if I had to pay 
retail for the GIM controller I'm using then I'd be well over that.  So far I 
think I'm at about $200 Cdn.  plus I'm using one of the first prototype GIMs I 
build almost 10 years ago.

https://www.kurtworkholding.com/product/kurt-bridgeport-series-i-std-2-j/

What happens with yours if you pressed the unload button for 5 seconds?  
Obviously the tool would drop out.  But does anything else unscrew or require 
manual operations to put back?


> -Original Message-
> From: John Figie [mailto:zephyr9...@gmail.com]
> Sent: November-22-21 2:30 PM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Spindle positioning.
> 
> Instead of a drawbar with a hex end you could use the kind with a spline
> end like the ones that Kurt sells for their power drawbar. My Bridgeport
> came with a Kurt power drawbar. I have had it since around 2003. Still
> using the same drawbar. The socket looks kind of like a torx socket - maybe
> it is - I never looked at it that close. The Kurt uses butterfly impact
> kind of like yours. It just uses regulated air pressure. I just let it
> drive the drawbar for about 1 or 2 seconds. It has never stripped and I
> have never replaced the drawbar.  Tooling is NMTB 30. Home shop use only.
> 
> http://www.machineability.com/Bridgeport_series_II.html
> 
> John
> 
> 
> On Mon, Nov 22, 2021, 3:39 PM John Dammeyer  wrote:
> 
> > Hi Mathew,
> > I want to be able to swap easily and quickly between R8 and TTS.  Here's a
> > selection of some of the tooling.
> >
> > http://www.autoartisans.com/mill/ToolSelection.jpg
> >
> >  There's a full set of R8 collets of course.  The spring loaded Tap Holder
> > has a 3/4" shank so it really just needs a TTS collar to make it full TTS.
> >   The two gear cutter arbours for the different sized cutters.  Face mill.
> > Changing from a 1/4" drill bit means I have to swap out the TTS to install
> > the R8 based expensive 16mm JT3 ball bearing chuck.
> >
> > To change completely over to TTS is expensive.  To change to a mill with a
> > NMBT or CAT cone type is really expensive.   The lowest cost power toolbar
> > system was the butterfly wrench and air cylinder.  Cost escalated as the
> > ordered electric pneumatic valves just never showed up from China so I went
> > local.  Not really expensive but it adds up as do all the fittings.
> >
> > At this point I could see spending as much as $150 Cdn. for the planetary
> > gear and stepper combination.Still way less expensive than fully
> > switching over to TTS which I probably will over time but not all in one
> > shot.   And I'm not sure the TTS wouldn't slip with the 5/8" chuck holding
> > a 1" reduced shank drill bit.
> >
> > First step now is to wait for the 12 point deep socket.
> >
> > John
> >
> >
> > > -Original Message-
> > > From: Matthew Herd [mailto:herd.m...@gmail.com]
> > > Sent: November-22-21 10:49 AM
> > > To: Enhanced Machine Controller (EMC)
> > > Subject: Re: [Emc-users] Spindle positioning.
> > >
> > > Hi John,
> > >
> > > You don?t need pull studs on the R-8 collets, just thread the draw bar
> > into the collet. Either until it stops or loctite the draw bar at
> > > the right depth. Then use a Belleville washer and air cylinder setup
> > like Andy?s.
> > >
> > > Matt
> > >
> > > > On Nov 22, 2021, at 1:32 PM, John Dammeyer 
> > wrote:
> > > >
> > > > ?It's the lowering of the wrench that I don't have a lot of control
> > on.  It's pushed down hard enough to keep the draw bar on top of
> > > the spindle so as it turns it pushes the sometimes a bit stiff R8 all
> > the way down and out.  If it's allow to move upwards (or I haven't
> > > locked the quill) then the drawbar may unthread but I then have to push
> > on the draw bar.
> > > >
> > > > A sensor on the Z down may be what has to happen.  Then repeated tries
> > with blipping the air wrench until it goes down all the
> > > way is an option.
> > > >
> > > > Making a draw bar from oil hardening steel and hardening the head a
> > bit so it doesn't get carved away and ends up more slippery
> > > might also be a requirement.
> > > >
> > > > John
> > > >
> > > >
> > > >> -Original Message-
> > > >> From: andy pugh [mailto:bodge...@gmail.com]
> > > >> Sent: November-22-21 5:41 AM
> > > >> To: Enhanced Machine Controller (EMC)
> > > >> Subject: Re: [Emc-users] Spindle positioning.
> > > >>
> > > >>> On Mon, 22 Nov 2021 at 08:03, John Dammeyer 
> > wrote:
> > > >>>
> > > >>> One still has to line up the socket to the hex head of the drawbar.
> > And since it can be at any position relative to the spindle the
> > > >> sensing has to happen against the hex head.  Rotate spindle until hex
> > head is at a known position.
> > > >>
> > > >> How about:
> > > >>
> > > >> Lower the wrench, but don't turn it on.
> > > >> Rotate the spindle until the wrench drops down to the "engaged" height
> > > >> (sensor on the slide)
> > > >> Then operate 

Re: [Emc-users] Spindle positioning.

[Gene Heskett]

On Monday 22 November 2021 16:35:37 John Dammeyer wrote:

> Hi Mathew,
> I want to be able to swap easily and quickly between R8 and TTS. 
> Here's a selection of some of the tooling.
>
> http://www.autoartisans.com/mill/ToolSelection.jpg
>
I've quite a bit more than that John but not the variety. I do any 
slotting I need with EDM. Just as precise, slower too, but no smearing 
of the slot edges.

>  There's a full set of R8 collets of course.  The spring loaded Tap
> Holder has a 3/4" shank so it really just needs a TTS collar to make
> it full TTS.The two gear cutter arbors for the different sized
> cutters.  Face mill.  Changing from a 1/4" drill bit means I have to
> swap out the TTS to install the R8 based expensive 16mm JT3 ball
> bearing chuck.
>
> To change completely over to TTS is expensive.

And gets you slippery tool holding because its pure friction.

> To change to a mill 
> with a NMBT or CAT cone type is really expensive.   The lowest cost
> power toolbar system was the butterfly wrench and air cylinder.  Cost
> escalated as the ordered electric pneumatic valves just never showed
> up from China so I went local.  Not really expensive but it adds up as
> do all the fittings.
>
> At this point I could see spending as much as $150 Cdn. for the
> planetary gear and stepper combination.Still way less expensive
> than fully switching over to TTS which I probably will over time but
> not all in one shot.   And I'm not sure the TTS wouldn't slip with the
> 5/8" chuck holding a 1" reduced shank drill bit.

I'm sure it will if the mill has the cajones to turn a 1" bit at the 
recommended speed and feed per rev. The fix is a notch in the edge of an 
r8, fits the head of a 4mm cap screw installed in the chuck adapter 
shank.  That leaves the next weak point the pin that engages the slot in 
the side of the r8 to keep the r8 from slipping in the spindle. IMO 
thats too small to turn a 1" bit with. It will shear. The question is 
when, not if.
>
> First step now is to wait for the 12 point deep socket.
>
> John
[...]

Take care John.

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, 1940)
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

Re: [Emc-users] Spindle positioning.

[John Figie]

Instead of a drawbar with a hex end you could use the kind with a spline
end like the ones that Kurt sells for their power drawbar. My Bridgeport
came with a Kurt power drawbar. I have had it since around 2003. Still
using the same drawbar. The socket looks kind of like a torx socket - maybe
it is - I never looked at it that close. The Kurt uses butterfly impact
kind of like yours. It just uses regulated air pressure. I just let it
drive the drawbar for about 1 or 2 seconds. It has never stripped and I
have never replaced the drawbar.  Tooling is NMTB 30. Home shop use only.

http://www.machineability.com/Bridgeport_series_II.html

John


On Mon, Nov 22, 2021, 3:39 PM John Dammeyer  wrote:

> Hi Mathew,
> I want to be able to swap easily and quickly between R8 and TTS.  Here's a
> selection of some of the tooling.
>
> http://www.autoartisans.com/mill/ToolSelection.jpg
>
>  There's a full set of R8 collets of course.  The spring loaded Tap Holder
> has a 3/4" shank so it really just needs a TTS collar to make it full TTS.
>   The two gear cutter arbours for the different sized cutters.  Face mill.
> Changing from a 1/4" drill bit means I have to swap out the TTS to install
> the R8 based expensive 16mm JT3 ball bearing chuck.
>
> To change completely over to TTS is expensive.  To change to a mill with a
> NMBT or CAT cone type is really expensive.   The lowest cost power toolbar
> system was the butterfly wrench and air cylinder.  Cost escalated as the
> ordered electric pneumatic valves just never showed up from China so I went
> local.  Not really expensive but it adds up as do all the fittings.
>
> At this point I could see spending as much as $150 Cdn. for the planetary
> gear and stepper combination.Still way less expensive than fully
> switching over to TTS which I probably will over time but not all in one
> shot.   And I'm not sure the TTS wouldn't slip with the 5/8" chuck holding
> a 1" reduced shank drill bit.
>
> First step now is to wait for the 12 point deep socket.
>
> John
>
>
> > -Original Message-
> > From: Matthew Herd [mailto:herd.m...@gmail.com]
> > Sent: November-22-21 10:49 AM
> > To: Enhanced Machine Controller (EMC)
> > Subject: Re: [Emc-users] Spindle positioning.
> >
> > Hi John,
> >
> > You don�t need pull studs on the R-8 collets, just thread the draw bar
> into the collet. Either until it stops or loctite the draw bar at
> > the right depth. Then use a Belleville washer and air cylinder setup
> like Andy�s.
> >
> > Matt
> >
> > > On Nov 22, 2021, at 1:32 PM, John Dammeyer 
> wrote:
> > >
> > > ?It's the lowering of the wrench that I don't have a lot of control
> on.  It's pushed down hard enough to keep the draw bar on top of
> > the spindle so as it turns it pushes the sometimes a bit stiff R8 all
> the way down and out.  If it's allow to move upwards (or I haven't
> > locked the quill) then the drawbar may unthread but I then have to push
> on the draw bar.
> > >
> > > A sensor on the Z down may be what has to happen.  Then repeated tries
> with blipping the air wrench until it goes down all the
> > way is an option.
> > >
> > > Making a draw bar from oil hardening steel and hardening the head a
> bit so it doesn't get carved away and ends up more slippery
> > might also be a requirement.
> > >
> > > John
> > >
> > >
> > >> -Original Message-
> > >> From: andy pugh [mailto:bodge...@gmail.com]
> > >> Sent: November-22-21 5:41 AM
> > >> To: Enhanced Machine Controller (EMC)
> > >> Subject: Re: [Emc-users] Spindle positioning.
> > >>
> > >>> On Mon, 22 Nov 2021 at 08:03, John Dammeyer 
> wrote:
> > >>>
> > >>> One still has to line up the socket to the hex head of the drawbar.
> And since it can be at any position relative to the spindle the
> > >> sensing has to happen against the hex head.  Rotate spindle until hex
> head is at a known position.
> > >>
> > >> How about:
> > >>
> > >> Lower the wrench, but don't turn it on.
> > >> Rotate the spindle until the wrench drops down to the "engaged" height
> > >> (sensor on the slide)
> > >> Then operate the wrench.
> > >>
> > >> --
> > >> 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
> > >
> > >
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
>
> ___
> Emc-users mailing list

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

Hi Mathew,
I want to be able to swap easily and quickly between R8 and TTS.  Here's a 
selection of some of the tooling. 

http://www.autoartisans.com/mill/ToolSelection.jpg

 There's a full set of R8 collets of course.  The spring loaded Tap Holder has 
a 3/4" shank so it really just needs a TTS collar to make it full TTS.The 
two gear cutter arbours for the different sized cutters.  Face mill.  Changing 
from a 1/4" drill bit means I have to swap out the TTS to install the R8 based 
expensive 16mm JT3 ball bearing chuck.

To change completely over to TTS is expensive.  To change to a mill with a NMBT 
or CAT cone type is really expensive.   The lowest cost power toolbar system 
was the butterfly wrench and air cylinder.  Cost escalated as the ordered 
electric pneumatic valves just never showed up from China so I went local.  Not 
really expensive but it adds up as do all the fittings.

At this point I could see spending as much as $150 Cdn. for the planetary gear 
and stepper combination.Still way less expensive than fully switching over 
to TTS which I probably will over time but not all in one shot.   And I'm not 
sure the TTS wouldn't slip with the 5/8" chuck holding a 1" reduced shank drill 
bit.

First step now is to wait for the 12 point deep socket.  

John


> -Original Message-
> From: Matthew Herd [mailto:herd.m...@gmail.com]
> Sent: November-22-21 10:49 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Spindle positioning.
> 
> Hi John,
> 
> You don�t need pull studs on the R-8 collets, just thread the draw bar into 
> the collet. Either until it stops or loctite the draw bar at
> the right depth. Then use a Belleville washer and air cylinder setup like 
> Andy�s.
> 
> Matt
> 
> > On Nov 22, 2021, at 1:32 PM, John Dammeyer  wrote:
> >
> > ?It's the lowering of the wrench that I don't have a lot of control on.  
> > It's pushed down hard enough to keep the draw bar on top of
> the spindle so as it turns it pushes the sometimes a bit stiff R8 all the way 
> down and out.  If it's allow to move upwards (or I haven't
> locked the quill) then the drawbar may unthread but I then have to push on 
> the draw bar.
> >
> > A sensor on the Z down may be what has to happen.  Then repeated tries with 
> > blipping the air wrench until it goes down all the
> way is an option.
> >
> > Making a draw bar from oil hardening steel and hardening the head a bit so 
> > it doesn't get carved away and ends up more slippery
> might also be a requirement.
> >
> > John
> >
> >
> >> -Original Message-
> >> From: andy pugh [mailto:bodge...@gmail.com]
> >> Sent: November-22-21 5:41 AM
> >> To: Enhanced Machine Controller (EMC)
> >> Subject: Re: [Emc-users] Spindle positioning.
> >>
> >>> On Mon, 22 Nov 2021 at 08:03, John Dammeyer  
> >>> wrote:
> >>>
> >>> One still has to line up the socket to the hex head of the drawbar.  And 
> >>> since it can be at any position relative to the spindle the
> >> sensing has to happen against the hex head.  Rotate spindle until hex head 
> >> is at a known position.
> >>
> >> How about:
> >>
> >> Lower the wrench, but don't turn it on.
> >> Rotate the spindle until the wrench drops down to the "engaged" height
> >> (sensor on the slide)
> >> Then operate the wrench.
> >>
> >> --
> >> 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
> >
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
> 
> 
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users



___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[Matthew Herd]

Hi John,

You don’t need pull studs on the R-8 collets, just thread the draw bar into the 
collet. Either until it stops or loctite the draw bar at the right depth. Then 
use a Belleville washer and air cylinder setup like Andy’s. 

Matt

> On Nov 22, 2021, at 1:32 PM, John Dammeyer  wrote:
> 
> It's the lowering of the wrench that I don't have a lot of control on.  It's 
> pushed down hard enough to keep the draw bar on top of the spindle so as it 
> turns it pushes the sometimes a bit stiff R8 all the way down and out.  If 
> it's allow to move upwards (or I haven't locked the quill) then the drawbar 
> may unthread but I then have to push on the draw bar.
> 
> A sensor on the Z down may be what has to happen.  Then repeated tries with 
> blipping the air wrench until it goes down all the way is an option.  
> 
> Making a draw bar from oil hardening steel and hardening the head a bit so it 
> doesn't get carved away and ends up more slippery might also be a requirement.
> 
> John
> 
> 
>> -Original Message-
>> From: andy pugh [mailto:bodge...@gmail.com]
>> Sent: November-22-21 5:41 AM
>> To: Enhanced Machine Controller (EMC)
>> Subject: Re: [Emc-users] Spindle positioning.
>> 
>>> On Mon, 22 Nov 2021 at 08:03, John Dammeyer  wrote:
>>> 
>>> One still has to line up the socket to the hex head of the drawbar.  And 
>>> since it can be at any position relative to the spindle the
>> sensing has to happen against the hex head.  Rotate spindle until hex head 
>> is at a known position.
>> 
>> How about:
>> 
>> Lower the wrench, but don't turn it on.
>> Rotate the spindle until the wrench drops down to the "engaged" height
>> (sensor on the slide)
>> Then operate the wrench.
>> 
>> --
>> 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
> 
> 
> 
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

It's the lowering of the wrench that I don't have a lot of control on.  It's 
pushed down hard enough to keep the draw bar on top of the spindle so as it 
turns it pushes the sometimes a bit stiff R8 all the way down and out.  If it's 
allow to move upwards (or I haven't locked the quill) then the drawbar may 
unthread but I then have to push on the draw bar.

A sensor on the Z down may be what has to happen.  Then repeated tries with 
blipping the air wrench until it goes down all the way is an option.  

Making a draw bar from oil hardening steel and hardening the head a bit so it 
doesn't get carved away and ends up more slippery might also be a requirement.

John


> -Original Message-
> From: andy pugh [mailto:bodge...@gmail.com]
> Sent: November-22-21 5:41 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Spindle positioning.
> 
> On Mon, 22 Nov 2021 at 08:03, John Dammeyer  wrote:
> 
> > One still has to line up the socket to the hex head of the drawbar.  And 
> > since it can be at any position relative to the spindle the
> sensing has to happen against the hex head.  Rotate spindle until hex head is 
> at a known position.
> 
> How about:
> 
> Lower the wrench, but don't turn it on.
> Rotate the spindle until the wrench drops down to the "engaged" height
> (sensor on the slide)
> Then operate the wrench.
> 
> --
> 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



___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

> From: Sam Sokolik [mailto:samco...@gmail.com]
> 
> Can you backdrive the impact wrench?  Keep it engaged?
> 
At the moment the loudest part of my system is the splined spindle shaft 
rattling in the splined pulley drive.  Especially with light cuts or not 
engaged.  Really quite annoying.  Once fully loaded it doesn't rattle of 
course.  But cheap far east mill design or construction has created one issue 
that ultimately I'd like to fix but that would remove the ability to have the 
quill go up and down for manual operations.

A permanent connection between socket and draw bar given that it's not a tight 
fit either would add secondary rattle.  Even more annoying. 

And I'm not sure if the impact wrench could handle that.

BTW, I took apart the old impact driver and the planetary gearbox inside is 
really nice.  Also with a 12V supply that immediately current limited at 3A it 
turned slowly.  So with a big enough 12V supply the old impact driver could be 
put into service.  Not sure how well the hex driver to 3/8" socket would last 
but that's a potential spot for an encoder disk too.

Need to think about this for a day or so.
John




___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

The problem is the air wrench turns freely unlike the electric impact wrenches. 
 So if it even just drops on the wrong point it then stays there and tracks the 
spindle turning.  Been there.  Tried that.  
John


> -Original Message-
> From: Gene Heskett [mailto:ghesk...@shentel.net]
> Sent: November-22-21 7:06 AM
> To: emc-users@lists.sourceforge.net
> Subject: Re: [Emc-users] Spindle positioning.
> 
> On Monday 22 November 2021 07:01:27 Roland Jollivet wrote:
> 
> > You probably don't need more than 1 bar on the lifting air cylinder,
> > up or down. No need to force it down.
> > So let it down, then if you can give the spindle a 1RPM burst to let
> > the nut slip over.
> > And have a switch on driver Z to know if it's down over the nut.
> >
> > You could also stop the spindle and descend the driver as the spindle
> > reaches it's last 5RPM? before stopping.
> 
> With my spindle, it would be stopped before it dropped a mm BUT rig a
> lever to push the lock pin AND have the motor running at gear change
> speeds. The wrench would fall, pressing on the lock pin, put half a bar
> down pressure one second after initiating the move, the spindle would
> match the nut and the socket falls over it. At that point it all turns
> until the lock pin falls into the hole which would close the engaged
> switch telling linuxcnc to stop the spindle, the wrench is in position
> to initiate the unlock. bring in the carousel, do the unlock, terminate
> the unlock on the second pulse from the magnet. The tool should drop
> into the waiting carousel pocket it came out of. Raise the head for
> clearance to turn the carousel, turn it to the selected tool, drop the
> head onto that tool and drive the air motor in the oposite direction
> long enough to get a good grip on the tool. raise the head, get the
> carousel out of the way and lift the air motor and socket back off the
> nut, releasing the lock pin. Give it a second to hit the upper stop, and
> let linuxcnc restart full spindle control.  No spindle to nut
> positioning needed. M6 t# is done. Most of it is sequenced by classic
> ladder code. restart the spindle in creep speed fwd to release the pin
> and nut at the end of the lockup. Tally switch the upper stop to let
> linuxcnc know its safe to TLO measure this tool, spin up the spindle and
> get back to work.  Whats not to like?
> 
> > Roland
> >
> > On Mon, 22 Nov 2021 at 10:03, John Dammeyer 
> wrote:
> > > > From: dave engvall [mailto:dengv...@charter.net]
> > > >
> > > > On 11/21/21 9:24 PM, John Dammeyer wrote:
> > > > > Is there a way to tell the spindle to turn until it finds the
> > > > > index
> > >
> > > and stop so it's always stopping at the exact same spot?  Like
> > >
> > > > decelerate to 0.5 rev per second  (30 RPM) or slower and stop when
> > > > the
> > >
> > > index happens?  With either an M5 or the button on the
> > >
> > > > user interface?
> > > >
> > > > If I were? doing that? today I would use 3 sensors. IOW a guard
> > > > sensor either side of index, rotate quickly to detection of guard
> > > > slow way down and search for the central sensor. How you know
> > > > which is the shortest path is left as an exercise for the
> > > > "student". ;-) Or maybe one simply defaults to searching in one
> > > > direction.
> > > >
> > > > If you don't need orientation then a stepper motor and a gear
> > > > would seem to be as simplistic as one can get.
> > > >
> > > > Dave
> > >
> > > One still has to line up the socket to the hex head of the drawbar.
> > > And since it can be at any position relative to the spindle the
> > > sensing has to happen against the hex head.  Rotate spindle until
> > > hex head is at a known position.  Then rotate socket from and
> > > indexed position until it matches the socket and then send it down.
> > > This could all happen in under 100mS and be almost transparent to an
> > > end user.
> > >
> > > There are times where I wish I had BMT-30 cone type tooling or just
> > > only TTS.
> > > John
> > >
> > >
> > >
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> > ___
> > 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, 1940)
> 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



___
Emc-users mailing list

Re: [Emc-users] Closed loop control of air motors.

[John Dammeyer]

Andy
If I was only running TTS or something with a pull stud like yours that would 
be a no brainer.  

However I want the ability to use both TTS (no more than two turns either 
direction) and R8 (engaged thread number of turns to release and capture).

The idea of tap on the button to force two turns and press and hold for 
continuous would work if I could get the socket to line up and the motor to not 
over speed to thousands of RPM.

I'll take a longer look at guiding the socket but in the end not all R8 tooling 
starts the thread at the same point.  So the draw bar engages at a different 
angle into each R8 collet so even if the spindle were at the index position 
where the nut ends up when tight will be different.  

Now if I had a slotted disk or reflective mark on the nut I could turn the 
spindle until that was detected and stop there.  Now we know where the flat is. 
 A tab on the socket that stops the socket turning in the up position would 
then allow a short blip on the air wrench to locate the socket close enough so 
when it then goes down is guided over the drawbar bolt head.   

Hence my other question about turning the spindle with the MESA 7i92H step/dir 
module in position mode or catching an index position.

John


> -Original Message-
> From: andy pugh [mailto:bodge...@gmail.com]
> Sent: November-22-21 5:26 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Closed loop control of air motors.
> 
> On Mon, 22 Nov 2021 at 05:23, John Dammeyer  wrote:
> 
> > As it is the nut is getting pretty trashed so until the 12 point socket 
> > arrives I think this part of the project is on hold.
> 
> Is it time to cut your losses and go with a Bellville washer stack?
> It works for Tormach: https://tormach.com/power-drawbar-pcnc-1100-31706.html
> (and, for that matter, for me: https://youtu.be/mZWQvq-X7DQ )
> 
> --
> 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



___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

First of all.  Way cool video.  Thanks for that link.  Didn't even speed 
through it.

A pull stud on R8 tools.  Interesting concept.  Not sure there's room inside 
the spindle for that.

John


> -Original Message-
> From: Matthew Herd [mailto:herd.m...@gmail.com]
> Sent: November-22-21 4:15 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] Spindle positioning.
> 
> What about a custom draw bar with an Andy Pugh style air cylinder release?  
> Seems simpler to engineer the mechanism than do all
> this control. Just have a drawbar that�s normally retracted with a flange. 
> Engage the flange with a mechanism on an air cylinder to
> release.
> 
> https://m.youtube.com/watch?v=mZWQvq-X7DQ
> 
> I think you could probably adapt the idea without the need to make your own 
> air cylinder, but the idea is sound.  No need to invent
> pull studs or pull stud fingers either. Just thread the other end of the draw 
> bar into the collet. Preferably with some Loctite or a
> similar solution.
> 
> Matt
> 
> >
> > On Nov 22, 2021, at 7:06 AM, Roland Jollivet  
> > wrote:
> >
> > ?You probably don't need more than 1 bar on the lifting air cylinder, up or
> > down. No need to force it down.
> > So let it down, then if you can give the spindle a 1RPM burst to let the
> > nut slip over.
> > And have a switch on driver Z to know if it's down over the nut.
> >
> > You could also stop the spindle and descend the driver as the spindle
> > reaches it's last 5RPM? before stopping.
> >
> > Roland
> >
> 
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users



___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[Sam Sokolik]

Can you backdrive the impact wrench?  Keep it engaged?

On Mon, Nov 22, 2021 at 11:45 AM John Dammeyer 
wrote:

> Thanks Roland,
> What I've found is that once the socket has reached that midpoint between
> flats it sticks there.  Rounding off the edges of the inside didn't fix it
> but did help.  I can even shut off the air so I can pull it down slowly
> against the return spring pressure and turn the spindle carefully by hand
> and I can still make it stick in that one area.
>
> The problem with turning the spindle is that the socket spins freely in
> the wrench so even the slightest bit of friction once it touches the nut
> causes it to turn with the spindle.  I tried 1RPM all the way up to 30RPM
> and it didn't matter.  The rounding of the nut and socket means 50% of the
> time it works perfectly and the other 50% sticks.
>
> Also if my set screw is too loose then on the way up the socket pulls
> out.  And the set screw loosens after about 10 cylces.  Hardened metal
> against hardened metal doesn't work well.  A softer screw didn't work much
> better.  Way to much rattle on the socket/driver connection.
>
> I never thought I'd have this much trouble...
> John
>
>
> > -Original Message-
> > From: Roland Jollivet [mailto:roland.jolli...@gmail.com]
> > Sent: November-22-21 4:01 AM
> > To: Enhanced Machine Controller (EMC)
> > Subject: [Emc-users] Spindle positioning.
> >
> > You probably don't need more than 1 bar on the lifting air cylinder, up
> or
> > down. No need to force it down.
> > So let it down, then if you can give the spindle a 1RPM burst to let the
> > nut slip over.
> > And have a switch on driver Z to know if it's down over the nut.
> >
> > You could also stop the spindle and descend the driver as the spindle
> > reaches it's last 5RPM? before stopping.
> >
> > Roland
> >
> >
> >
> > On Mon, 22 Nov 2021 at 10:03, John Dammeyer 
> wrote:
> >
> > >
> > > > From: dave engvall [mailto:dengv...@charter.net]
> > > > On 11/21/21 9:24 PM, John Dammeyer wrote:
> > > > > Is there a way to tell the spindle to turn until it finds the index
> > > and stop so it's always stopping at the exact same spot?  Like
> > > > decelerate to 0.5 rev per second  (30 RPM) or slower and stop when
> the
> > > index happens?  With either an M5 or the button on the
> > > > user interface?
> > > > >
> > > > If I were? doing that? today I would use 3 sensors. IOW a guard
> sensor
> > > > either side of index, rotate quickly to detection of guard slow way
> down
> > > > and search for the central sensor. How you know which is the shortest
> > > > path is left as an exercise for the "student". ;-) Or maybe one
> simply
> > > > defaults to searching in one direction.
> > > >
> > > > If you don't need orientation then a stepper motor and a gear would
> seem
> > > > to be as simplistic as one can get.
> > > >
> > > > Dave
> > >
> > > One still has to line up the socket to the hex head of the drawbar.
> And
> > > since it can be at any position relative to the spindle the sensing
> has to
> > > happen against the hex head.  Rotate spindle until hex head is at a
> known
> > > position.  Then rotate socket from and indexed position until it
> matches
> > > the socket and then send it down.  This could all happen in under
> 100mS and
> > > be almost transparent to an end user.
> > >
> > > There are times where I wish I had BMT-30 cone type tooling or just
> only
> > > TTS.
> > > John
> > >
> > >
> > >
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>

___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Special for dave engvall

[Gene Heskett]

Apparently charter has blocked me as a spammer, I am not getting answers 
to my msgs sent since yesterday afternoon.

Check your mail at charter with a browser, looking in the spam folder, if 
I'm in there, spank em.

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, 1940)
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

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

Thanks Roland,
What I've found is that once the socket has reached that midpoint between flats 
it sticks there.  Rounding off the edges of the inside didn't fix it but did 
help.  I can even shut off the air so I can pull it down slowly against the 
return spring pressure and turn the spindle carefully by hand and I can still 
make it stick in that one area.

The problem with turning the spindle is that the socket spins freely in the 
wrench so even the slightest bit of friction once it touches the nut causes it 
to turn with the spindle.  I tried 1RPM all the way up to 30RPM and it didn't 
matter.  The rounding of the nut and socket means 50% of the time it works 
perfectly and the other 50% sticks.

Also if my set screw is too loose then on the way up the socket pulls out.  And 
the set screw loosens after about 10 cylces.  Hardened metal against hardened 
metal doesn't work well.  A softer screw didn't work much better.  Way to much 
rattle on the socket/driver connection.

I never thought I'd have this much trouble...
John


> -Original Message-
> From: Roland Jollivet [mailto:roland.jolli...@gmail.com]
> Sent: November-22-21 4:01 AM
> To: Enhanced Machine Controller (EMC)
> Subject: [Emc-users] Spindle positioning.
> 
> You probably don't need more than 1 bar on the lifting air cylinder, up or
> down. No need to force it down.
> So let it down, then if you can give the spindle a 1RPM burst to let the
> nut slip over.
> And have a switch on driver Z to know if it's down over the nut.
> 
> You could also stop the spindle and descend the driver as the spindle
> reaches it's last 5RPM? before stopping.
> 
> Roland
> 
> 
> 
> On Mon, 22 Nov 2021 at 10:03, John Dammeyer  wrote:
> 
> >
> > > From: dave engvall [mailto:dengv...@charter.net]
> > > On 11/21/21 9:24 PM, John Dammeyer wrote:
> > > > Is there a way to tell the spindle to turn until it finds the index
> > and stop so it's always stopping at the exact same spot?  Like
> > > decelerate to 0.5 rev per second  (30 RPM) or slower and stop when the
> > index happens?  With either an M5 or the button on the
> > > user interface?
> > > >
> > > If I were? doing that? today I would use 3 sensors. IOW a guard sensor
> > > either side of index, rotate quickly to detection of guard slow way down
> > > and search for the central sensor. How you know which is the shortest
> > > path is left as an exercise for the "student". ;-) Or maybe one simply
> > > defaults to searching in one direction.
> > >
> > > If you don't need orientation then a stepper motor and a gear would seem
> > > to be as simplistic as one can get.
> > >
> > > Dave
> >
> > One still has to line up the socket to the hex head of the drawbar.  And
> > since it can be at any position relative to the spindle the sensing has to
> > happen against the hex head.  Rotate spindle until hex head is at a known
> > position.  Then rotate socket from and indexed position until it matches
> > the socket and then send it down.  This could all happen in under 100mS and
> > be almost transparent to an end user.
> >
> > There are times where I wish I had BMT-30 cone type tooling or just only
> > TTS.
> > John
> >
> >
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> 
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users



___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Closed loop control of air motors.

[Gene Heskett]

On Monday 22 November 2021 07:07:45 Gregg Eshelman via Emc-users wrote:

> How about an eddy current brake that uses a thick copper washer, a
> disk with some strong magnets, and use a small air cylinder to push
> the copper washer away from the magnets and springs to pull or push it
> close to the magnets when the air is cut off so the wrench stops fast.

Since eddy currents are speed sensitive, I see no need to disengage. what 
I do see is a lack of space to build it in since its effect would need a 
larger diameter copper disk than there is room for in Johns wrench 
mount. Lurking in the back of my mind is a very short pulse of air in 
fwd to stop the overspin once its unlocked.

The air valve I am using to switch the mister air on the 6040 may be 
different from the one John is using, this one stops by venting the 
pressure in the out port to atmosphere with a pop, and I got it from 
some outfit that specializes in air horns for large cars. It may be that 
the venting would stop most of the overspin. Its only problem is that I 
don't think the coil maker figured on CCS operation as it runs way 
hotter than that famous little red wagon when its been on for 45 
minutes. I've no clue if a bidir valve that does that is available.

Something else for John to investigate. I think a 2 spool could do it, 
one to control the air, feeding one to do the reversal. My guess is that 
the one doing the reversal probably can't switch while the pressure is 
on. Oneshots in the hal file can fix that so I don't see that as a real 
problem. 

But you get that eddy current braking effect for free by using the 
battery impact screwdriver because the bts-7960 crowbars the motor in 
the off mode. You can turn it by hand, but not very fast. From wide open 
to stopped is about 1 turn.

> Automatic brake release and fail safe engagement, but zero contact so
> there's nothing to wear out or jam up.
>
>   On Sunday, November 21, 2021, 07:57:34 AM MST, Gene Heskett
>  wrote: Close to the truth, However there might
> be a salvation in a viscous greased disk that would absorb the rapid
> spin, trapped between two other disks. It would allow the initial slow
> unlocking but seriously impede the following rapid spin. Or an eddy
> currant brake but that would take burn it up power so it would need to
> be applied only when the air is applied, and possibly for half a
> second after the air valve was turned off. I like the suicide braking
> idea, but there is limited space and it needs more diameter than you
> have room for. A coil spring anchored to the tool that would allow
> maybe three turns of the socket before winding tight against the
> socket OD might be a softer stop. Or a pile of interlocking disks that
> were screw driven like the rear brakes on an old Schwinn bicycle? 
> That was fairly compact and lasted close to forever.
>
> Just tossing out ideas to see if one sticks.
>
> Cheers, Gene Heskett.
> ___
> 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, 1940)
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

Re: [Emc-users] Spindle positioning.

[Gene Heskett]

On Monday 22 November 2021 07:01:27 Roland Jollivet wrote:

> You probably don't need more than 1 bar on the lifting air cylinder,
> up or down. No need to force it down.
> So let it down, then if you can give the spindle a 1RPM burst to let
> the nut slip over.
> And have a switch on driver Z to know if it's down over the nut.
>
> You could also stop the spindle and descend the driver as the spindle
> reaches it's last 5RPM? before stopping.

With my spindle, it would be stopped before it dropped a mm BUT rig a 
lever to push the lock pin AND have the motor running at gear change 
speeds. The wrench would fall, pressing on the lock pin, put half a bar 
down pressure one second after initiating the move, the spindle would 
match the nut and the socket falls over it. At that point it all turns 
until the lock pin falls into the hole which would close the engaged 
switch telling linuxcnc to stop the spindle, the wrench is in position 
to initiate the unlock. bring in the carousel, do the unlock, terminate 
the unlock on the second pulse from the magnet. The tool should drop 
into the waiting carousel pocket it came out of. Raise the head for 
clearance to turn the carousel, turn it to the selected tool, drop the 
head onto that tool and drive the air motor in the oposite direction 
long enough to get a good grip on the tool. raise the head, get the 
carousel out of the way and lift the air motor and socket back off the 
nut, releasing the lock pin. Give it a second to hit the upper stop, and 
let linuxcnc restart full spindle control.  No spindle to nut 
positioning needed. M6 t# is done. Most of it is sequenced by classic 
ladder code. restart the spindle in creep speed fwd to release the pin 
and nut at the end of the lockup. Tally switch the upper stop to let 
linuxcnc know its safe to TLO measure this tool, spin up the spindle and 
get back to work.  Whats not to like?

> Roland
>
> On Mon, 22 Nov 2021 at 10:03, John Dammeyer  
wrote:
> > > From: dave engvall [mailto:dengv...@charter.net]
> > >
> > > On 11/21/21 9:24 PM, John Dammeyer wrote:
> > > > Is there a way to tell the spindle to turn until it finds the
> > > > index
> >
> > and stop so it's always stopping at the exact same spot?  Like
> >
> > > decelerate to 0.5 rev per second  (30 RPM) or slower and stop when
> > > the
> >
> > index happens?  With either an M5 or the button on the
> >
> > > user interface?
> > >
> > > If I were� doing that� today I would use 3 sensors. IOW a guard
> > > sensor either side of index, rotate quickly to detection of guard
> > > slow way down and search for the central sensor. How you know
> > > which is the shortest path is left as an exercise for the
> > > "student". ;-) Or maybe one simply defaults to searching in one
> > > direction.
> > >
> > > If you don't need orientation then a stepper motor and a gear
> > > would seem to be as simplistic as one can get.
> > >
> > > Dave
> >
> > One still has to line up the socket to the hex head of the drawbar. 
> > And since it can be at any position relative to the spindle the
> > sensing has to happen against the hex head.  Rotate spindle until
> > hex head is at a known position.  Then rotate socket from and
> > indexed position until it matches the socket and then send it down. 
> > This could all happen in under 100mS and be almost transparent to an
> > end user.
> >
> > There are times where I wish I had BMT-30 cone type tooling or just
> > only TTS.
> > John
> >
> >
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
> ___
> 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, 1940)
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

Re: [Emc-users] Spindle positioning.

[andy pugh]

On Mon, 22 Nov 2021 at 08:03, John Dammeyer  wrote:

> One still has to line up the socket to the hex head of the drawbar.  And 
> since it can be at any position relative to the spindle the sensing has to 
> happen against the hex head.  Rotate spindle until hex head is at a known 
> position.

How about:

Lower the wrench, but don't turn it on.
Rotate the spindle until the wrench drops down to the "engaged" height
(sensor on the slide)
Then operate the wrench.

-- 
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

Re: [Emc-users] Closed loop control of air motors.

[andy pugh]

On Mon, 22 Nov 2021 at 05:23, John Dammeyer  wrote:

> As it is the nut is getting pretty trashed so until the 12 point socket 
> arrives I think this part of the project is on hold.

Is it time to cut your losses and go with a Bellville washer stack?
It works for Tormach: https://tormach.com/power-drawbar-pcnc-1100-31706.html
(and, for that matter, for me: https://youtu.be/mZWQvq-X7DQ )

-- 
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

Re: [Emc-users] Closed loop control of air motors.

[andy pugh]

On Sun, 21 Nov 2021 at 07:45, John Dammeyer  wrote:
>
>  I'd like to be able to limit the number of turns to 2.

OK, here is a possible arrangement that will fit in the existing packaging.

Press a sleeve onto the outside of the socket with a spiral groove
machined into it (actually two grooves, a 2-start thread)
Sliding on the two uprights is a part that engages with the groove on
both sides.  We will call it "the slider"
The slider will initially travel down with the socket on engagement.
When running clockwise the grooves lift the slider up into a
continuous run-out groove at the top, so that clockwise rotation is
not restricted.
When running anticlockwise the slider is biased down (spring?
gravity?) into the spiral and descends for the full two / three turns
before getting to the end of the groove.

What happens then is open to development.

I can see that the slider could operate a switch to turn off the air
somewhere in its travel.
The slider could operate a friction disc at the bottom of travel. In
that embodiment the bottom would also have a continuous run-out groove
(but then the spring bias needs to be a collar top and bottom)

Alternatively the slider could just hit the ends of the grooves and
stop. Or the spiral ramp could be friction-coupled to the socket,
still with a hard-stop at the end of the ramp.

-- 
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

Re: [Emc-users] Spindle positioning.

[Matthew Herd]

What about a custom draw bar with an Andy Pugh style air cylinder release?  
Seems simpler to engineer the mechanism than do all this control. Just have a 
drawbar that’s normally retracted with a flange. Engage the flange with a 
mechanism on an air cylinder to release. 

https://m.youtube.com/watch?v=mZWQvq-X7DQ

I think you could probably adapt the idea without the need to make your own air 
cylinder, but the idea is sound.  No need to invent pull studs or pull stud 
fingers either. Just thread the other end of the draw bar into the collet. 
Preferably with some Loctite or a similar solution. 

Matt

> 
> On Nov 22, 2021, at 7:06 AM, Roland Jollivet  
> wrote:
> 
> You probably don't need more than 1 bar on the lifting air cylinder, up or
> down. No need to force it down.
> So let it down, then if you can give the spindle a 1RPM burst to let the
> nut slip over.
> And have a switch on driver Z to know if it's down over the nut.
> 
> You could also stop the spindle and descend the driver as the spindle
> reaches it's last 5RPM? before stopping.
> 
> Roland
> 

___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Closed loop control of air motors.

[Gregg Eshelman via Emc-users]

How about an eddy current brake that uses a thick copper washer, a disk with 
some strong magnets, and use a small air cylinder to push the copper washer 
away from the magnets and springs to pull or push it close to the magnets when 
the air is cut off so the wrench stops fast.

Automatic brake release and fail safe engagement, but zero contact so there's 
nothing to wear out or jam up.

  On Sunday, November 21, 2021, 07:57:34 AM MST, Gene Heskett 
 wrote: 
Close to the truth, However there might be a salvation in a viscous 
greased disk that would absorb the rapid spin, trapped between two other 
disks. It would allow the initial slow unlocking but seriously impede 
the following rapid spin. Or an eddy currant brake but that would take 
burn it up power so it would need to be applied only when the air is 
applied, and possibly for half a second after the air valve was turned 
off. I like the suicide braking idea, but there is limited space and it 
needs more diameter than you have room for. A coil spring anchored to 
the tool that would allow maybe three turns of the socket before winding 
tight against the socket OD might be a softer stop. Or a pile of 
interlocking disks that were screw driven like the rear brakes on an old 
Schwinn bicycle?  That was fairly compact and lasted close to forever.

Just tossing out ideas to see if one sticks.

Cheers, Gene Heskett.  
___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

[Emc-users] Spindle positioning.

[Roland Jollivet]

You probably don't need more than 1 bar on the lifting air cylinder, up or
down. No need to force it down.
So let it down, then if you can give the spindle a 1RPM burst to let the
nut slip over.
And have a switch on driver Z to know if it's down over the nut.

You could also stop the spindle and descend the driver as the spindle
reaches it's last 5RPM? before stopping.

Roland



On Mon, 22 Nov 2021 at 10:03, John Dammeyer  wrote:

>
> > From: dave engvall [mailto:dengv...@charter.net]
> > On 11/21/21 9:24 PM, John Dammeyer wrote:
> > > Is there a way to tell the spindle to turn until it finds the index
> and stop so it's always stopping at the exact same spot?  Like
> > decelerate to 0.5 rev per second  (30 RPM) or slower and stop when the
> index happens?  With either an M5 or the button on the
> > user interface?
> > >
> > If I were� doing that� today I would use 3 sensors. IOW a guard sensor
> > either side of index, rotate quickly to detection of guard slow way down
> > and search for the central sensor. How you know which is the shortest
> > path is left as an exercise for the "student". ;-) Or maybe one simply
> > defaults to searching in one direction.
> >
> > If you don't need orientation then a stepper motor and a gear would seem
> > to be as simplistic as one can get.
> >
> > Dave
>
> One still has to line up the socket to the hex head of the drawbar.  And
> since it can be at any position relative to the spindle the sensing has to
> happen against the hex head.  Rotate spindle until hex head is at a known
> position.  Then rotate socket from and indexed position until it matches
> the socket and then send it down.  This could all happen in under 100mS and
> be almost transparent to an end user.
>
> There are times where I wish I had BMT-30 cone type tooling or just only
> TTS.
> John
>
>
>
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>

___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users

Re: [Emc-users] Spindle positioning.

[Gene Heskett]

On Monday 22 November 2021 02:48:36 John Dammeyer wrote:

> > I assume you have a similar, fixed position spindle lock? I had to
> > make mine.
>
> Nope.  As a friend said the other day when I asked if he'd found a
> lock on his... "I use a big hammer on the supplied wrench to tighten
> or loosen it".  He's since carved a 3/4" hex head on his and is now
> using his electric impact driver manually.
>
> > Doing that twice, to position the socket as its comes down to fully
> > engage the drawbar should be doable with a dup of the same idea, but
> > since that needs to be done while its up, maybe a second ring and
> > magnet on the socket to make it work in the up position. That would
> > also give you the rotational tweek for free. The impact driver, with
> > a short 1/4" hex to 3/8" adapter should solve the socket dropping
> > problem too.
>
> Humans are funny creatures.  We do things so easily that are difficult
> for a machine.  So we reach up and place the 6 point socket over the
> draw bar.  If it doesn't go down right away we just angle/tilt/twist
> the driver a bit until it slips down and then we press the trigger.
>
> My air cylinder just rams down the driver and the 6 point socket and
> even with rounding of the inside edges of the socket it's still been
> scraping away metal on the nut.  It's not looking great at the moment
> at the attached photo shows.  Hence I'm waiting for the 12 point deep
> socket.  I don't have enough adjustment space for a normal length 12
> point and most of the 19mm sockets appear to only be 6 point for some
> reason.

Most of the 19's are 6 because they fit older spark plugs too.

Timed right, the 6 point would be easier on the bolt. On my little g0704, 
its a 10mm square but I'm using an 8 point socket, I haven't found a 4 
point, doubt they are even made. A 12 point would likely wipe the 
corners off. The adapter locks into the tool, and the ball bearing 
detent in the 4 point 1/4" adapter grabs the socket pretty firmly. I'd 
assume the 3/8" adapter would be more than adequate to hold even the 
heavier deep socket.

> If I had a magnet on the drawbar nut assembly (or reflective tape) I
> could rotate the spindle until I know where the one of the 6 flats is.

Humm... There is probably a random thread start for different collets, I 
have them (r8 collets) from at least 5 makers making the flat random 
even if tight.  To reliaby find it, I think you'd have to put glossy 
paint on a fresh bolt with polished flats and search for the peak 
reflectance off the gloss to nail it down accurately enough. Paint it 
all, any flat would do.  And a 12 point wouldn't wear the paint off the 
middle of the flat, so the paint ought to last a long time.  And I'd use 
a dark paint, its the glossy reflectance peak you want to search for. 
Glossy black would probably be best. Its the gloss you want to use as a 
mirror. Off axis glossy black is the best black there is. Back when we 
used tube color tv cameras, making a good black adjustment was the most 
precious adjustment, so we often cut the black velvet out of the center 
of a linearity stair step card, putting a curved partial spiral painted 
glossy black on the inside, on the back of the hole. The gloss made the 
light going into that spiral, it bounces back and forth in the spiral 
until it was absorbed totaly, making a true black hole. Light goes in 
and never comes back out. Hell of a thing to do to a $600 card (1990 
prices)

>  At that point if I had fine enough control over the drive unit I
> could turn the socket until the flats were reasonably lined up before
> I send the socket down.
>
> Yes.  I'm making  this overly complicated.  It's what I do.  I can't
> help myself.  You are allowed to laugh. John
>
And I am, but It's not at you, its with you I hope...
I'm the same way but since I'm a CET, its the electronics that get the 
attention. And folks don't always see the magic, its hidden behind the 
poorly finished mechanics. So go ahead, laugh at my stuff but it usually 
works well.

That sheldon has been rode hard and put away wet, 13 thou of bed wear 
right in front of the spindle, but thanks to linuxcnc, it still cuts a 
pretty good cylinder 36" long.

Cheers John, 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, 1940)
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

Re: [Emc-users] Spindle positioning.

[John Dammeyer]

> From: dave engvall [mailto:dengv...@charter.net]
> On 11/21/21 9:24 PM, John Dammeyer wrote:
> > Is there a way to tell the spindle to turn until it finds the index and 
> > stop so it's always stopping at the exact same spot?  Like
> decelerate to 0.5 rev per second  (30 RPM) or slower and stop when the index 
> happens?  With either an M5 or the button on the
> user interface?
> >
> If I were� doing that� today I would use 3 sensors. IOW a guard sensor
> either side of index, rotate quickly to detection of guard slow way down
> and search for the central sensor. How you know which is the shortest
> path is left as an exercise for the "student". ;-) Or maybe one simply
> defaults to searching in one direction.
> 
> If you don't need orientation then a stepper motor and a gear would seem
> to be as simplistic as one can get.
> 
> Dave

One still has to line up the socket to the hex head of the drawbar.  And since 
it can be at any position relative to the spindle the sensing has to happen 
against the hex head.  Rotate spindle until hex head is at a known position.  
Then rotate socket from and indexed position until it matches the socket and 
then send it down.  This could all happen in under 100mS and be almost 
transparent to an end user.

There are times where I wish I had BMT-30 cone type tooling or just only TTS.
John




___
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users