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Author Topic: Problems threading on the lathe  (Read 330205 times)

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Offline Chip

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Re: Problems threading on the lathe
« Reply #260 on: April 26, 2009, 01:46:34 AM »
Hi, Art

Hears 4 pic's of my good computer with simulated, 1, 10, 99 and 999 num slots.

Chip

Offline ART

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Re: Problems threading on the lathe
« Reply #261 on: April 26, 2009, 07:38:53 AM »
Hi Chip.


Thx, you and rich have pretty good numbers,

your 99 slots seems to miss one slot per rev, and 999 seems to lose about 10.. thats interesting, we'll see how real world
conditions do. I still have one computer reading weirdly so whatever I find may reflect soem weakness somewhere, but you
two are fine fer now.

 Thx for the tests, preciate the results.

Art

Offline simpson36

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Re: Problems threading on the lathe
« Reply #262 on: April 26, 2009, 09:38:39 AM »
I have noticed what appear to be rounding errors in Mach on the cutter comp routines. If that is related, it may be a place to look. I've had problems like this as programs age and I am continuously modifying them. Usually it (if I ever find it) the problem is old variables without enough precision that never got updated.

Specifically, in Mach I get a distinct perpendicular axis shift at the tangent of two arcs when I used an cutter comp offset of .008 but changing to .009 eliminated the shift.

FWIW


BTW, is there any tought of adding a continuous rotation capability for servo motors?

Offline ART

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Re: Problems threading on the lathe
« Reply #263 on: April 30, 2009, 08:08:55 AM »

Hii:

 Brian has redone cutter comp for futre versions. It shouldnt round though, but arc intersections can get complex in calculation, and some variance can be expected depending
on the acuteness of the angles involved. If all works out , Im willing to add capability to the new Spindle control routines, but at the moment, Im focused only on threading.

Thx
Art

Offline ART

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Re: Problems threading on the lathe
« Reply #264 on: April 30, 2009, 08:18:16 AM »
Hi Guys:

  This is a threading slotted wheel Scoping test. Im looking for Ground effects or floating times. Id love ot see any captures you do on
this one. Just get your spindle going, and launch the scope, select # of samples and hit sample.

 If TIMING is disabled, it assumes input from Encoder#4 , otherwise a single slot input on TIMING input.

 My kernal is 25us per int on the photo's test, and I see a max 25us or so swing in time, this indicates a very flat and good responce to a very
good and stable input. Id like to see yours.

You need to install the enclosed driver and plugin to use this..

Thx
Art

Offline RICH

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Re: Problems threading on the lathe
« Reply #265 on: April 30, 2009, 06:04:09 PM »
ART,
Do you need version .027 for this test or will it work with 024?
RICH

Offline ART

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Re: Problems threading on the lathe
« Reply #266 on: April 30, 2009, 08:31:31 PM »
I think this test will work with any version, but the RPM detected will not be passed to MAch3 unless .027 version is installed. The Scope and such will work though in any version as long as this driver is loaded.

Art

Offline RICH

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Re: Problems threading on the lathe
« Reply #267 on: May 01, 2009, 12:21:42 AM »
ART,
The scope is not working for version 024 that i am using ?
With or without the sys file and fooling with the settings.
RICH

Offline ART

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Re: Problems threading on the lathe
« Reply #268 on: May 01, 2009, 09:52:32 AM »
Rich:

 Weird.. Does th eplugin show any slot times being seen? This scope only works on Encoder #4, or TIMING input.. If theres a TIMING input there it shoudl show up in the scope as well as in the plugins dialog as SLotTime
changing as the slots come in. If "LastSlotTime" is changing, then the Scope should work fine.. any version..

Art

Offline ART

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Re: Problems threading on the lathe
« Reply #269 on: May 01, 2009, 10:47:57 AM »
Rich:

  Here's another plugin, it reports each CPU and if it is set to throttle or not, you have to select a CPU number before it will report. If you have only 1 cpu they will all report the same. Does anyone report a throttling? All you need is the plugin for this test..

Thx
Art