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Author Topic: Problems threading on the lathe  (Read 330196 times)

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Offline ART

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Re: Problems threading on the lathe
« Reply #220 on: April 10, 2009, 10:27:56 PM »
Guys:

 Still trying to figure out why I have RPM, but you dont.. Can sopmeone put a DRO#72 on the screen and see
what it says while its turing..

Thx
ARt

Offline Chip

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Re: Problems threading on the lathe
« Reply #221 on: April 10, 2009, 10:39:57 PM »
Hi, Art

Yes, A little, Hears some pic's, Pulley ratio set to "1" now.

Dro39 was in the screen set I used,  ;D

Hears both DRO 39 & 72, Note,  First 3 pic's shown with  Pulse Freq 26479 solid, Last pic shows Pulse Freq 26024 slightly different value.

DRO 39 is Turn Spindle DRO

DRO 72 is Current Spindle Counts DRO

Chip
« Last Edit: April 11, 2009, 03:29:13 AM by Chip »

Offline Chip

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Re: Problems threading on the lathe
« Reply #222 on: April 11, 2009, 08:33:06 PM »
Hi, Art & All

Hears another pic, Pulley Ratio set to ".001", Just to compare.

Chip

Offline Chip

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Re: Problems threading on the lathe
« Reply #223 on: April 11, 2009, 08:58:47 PM »
Hi, ALL

Hears the Test Lathe. lset file, If you want to give it a try, Install it in C:Mach3 folder, It's a work in progress screen Lset.

You need also install the Zip file content (JPG's) in C:\Mach3\Bitmaps\MillBitmaps folder for the Pop-Out Pendent.

Chip

Offline RICH

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Re: Problems threading on the lathe
« Reply #224 on: April 12, 2009, 07:21:40 AM »
CHIP,
Thanks for the file posting. Don't know if  I'll get a chance to try them today.

RICH

Offline ART

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Re: Problems threading on the lathe
« Reply #225 on: April 12, 2009, 09:39:30 AM »
Chip:

  SO does that mean your getting a reading of spindle speed of 321.87xx over time, Is it really varying only .00xx as RPM?
I see its 1000 times greater than it shoudl be.. but other than that is it really that low a variation? Is that with averaging off?

And why does the pulse frequency read 8 thousand or so on the diags screen yu posted??

Thx
Art

Offline ART

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Re: Problems threading on the lathe
« Reply #226 on: April 12, 2009, 02:31:55 PM »
Hi Guys:

  Here is a driver and drivertest.exe, Id really liek to see a coupel screenshots form anyone willing to test it. A shot of the drivertest.exe runnign as per normal install, and then this one with the enclosed driver. I need to see the "Longest int" value, shoudl be -1 or -2 on most systems, and how the stability looks after lettig it run fro a few seconds to settle. The new drivertest uses the PIT timer on your motherboard. I need to know why Chip is 1000 times too high, and some of you get 0RPM .. This test may tell me that.

  Keep a copy of your old exe and sys file to copy them back and reinstall your normal driver after testing..

Thx
Art

Offline RICH

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Re: Problems threading on the lathe
« Reply #227 on: April 12, 2009, 11:22:22 PM »
ART,
Here are some screen shots using the driver test's.
The file name indicates which is which, namely, Normal Install and Reply 226 driver test.
RICH

REMARK:DELL GX520
« Last Edit: April 12, 2009, 11:31:06 PM by RICH »

Offline ART

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Re: Problems threading on the lathe
« Reply #228 on: April 12, 2009, 11:58:51 PM »
Hi Rich:

 Thx, seems some PIT interval timers arent at the sam eport as mine..

More tests soon of an enhancment to pulse timing that I found while working..
Shoudl make it up to 5us more stable for most people I think..

Art

Offline simpson36

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Re: Problems threading on the lathe
« Reply #229 on: April 13, 2009, 02:27:52 AM »
I've been folowing this thread off and on and I just want to throw an idea into the pot.

It seems to me that there may be a conflict between reading the RPM only once per rev and the built in power compensation in some variable speed controllers. I have an ammeter on the output of my Minarik brand drive and I can observe the power changing yet the RPM is (relatively) consistent.

For example, when the tool first starts cutting, the spindle will slow down. Then the variable speed conrtoller will compensate and throw more power at it.

If this all happens within one rotation, MACH has no ability to measure the actual speed that the spindle is turning at the END of the rotation since it only has available the time taken to complete one rotation. i.e. Mach would measure a lower speed since the initial slow down would be included in the total revolution period.

What I'm thinking is that Mach would adjust for the speed it thinks the spindle is turning based on the avilable info, namely the time interval of one revolution, when the spindle is actually turing at a higher speed becuase the controller has compensated and increased the power.

This scenario would self correct over a few revolutions as the rpm stabilized (assuming a relatively consistent stock density) during the cut. This seems to be consistent with the behavior people are experiencing.

If this is the case, more readings per rev would be a potential solution. In this way, Mach would become aware of deviation within one revolution which have been corrected within that revolution.