Hello Guest it is September 20, 2019, 09:26:46 PM

Author Topic: Problems threading on the lathe  (Read 330215 times)

0 Members and 1 Guest are viewing this topic.

Re: Problems threading on the lathe
« Reply #140 on: March 17, 2009, 11:01:57 AM »
Art, I am being pretty bold in kinda disagreeing with you since you are now doubt "the man", and I mean no offence, so let me appologize in advance, but there is absolutely no way that I am loosing 50% of my rpm.   The problem occurs for me with a much smaller loss of rpm as I have said before.  I feel very confident about this, but i will try to see if I can get time later today to test it one last time to make myself feel better about my standpoint.  If I am wrong I will be more than willing to admit it, but I am sure that I am not going from 400rpm down to 200 rpm while threading..........

Trevor
Re: Problems threading on the lathe
« Reply #141 on: March 17, 2009, 11:16:21 AM »
Hi Trevor,
  The "50%" caught my attention as well.
Perhaps you could hold off changing anything until ART provides his fix just to see if that corrects the problem on your end.
If not, we can go from there.
Regards,
Curious wimpy lathe runner,
RC
Re: Problems threading on the lathe
« Reply #142 on: March 17, 2009, 11:22:56 AM »
Sure, I will wait for the fix from art, this is all for fun for me anyway, I did just have a thought though, Art, would a reduction of 50 rpm do it?  I am still curious about the box under turning Diag showing a percentage label on it.  As I have said before if I have a reduction of 20 RPM it says 20% on the box.  Is this just a label that the program doesn't even care about, or is it actually seeing it a a 20% reduction, if so I could see a 50rpm loss being seen as a 50% loss.  I am probably grasping at straws, but I just don't think that all of us could be experiencing an "actual" real world loss of 50% of our set RPM.  One of us would have noticed that by now as there is a big diffirence between 200 and 400 rpm even with a puny lathe like some of us have.  I am excited though as I bet that you are close to a solution!!

Offline ART

*
  • *
  •  1,698 1,698
  • Tough as soggy paper.
    • View Profile
Re: Problems threading on the lathe
« Reply #143 on: March 17, 2009, 12:03:08 PM »
HI Guys:

  This is a matter of reference, Im speaking in terms of driver reading of the RPM. However, many systems are not pure in this sensing, sometimes a noise spike can occur and the system will run that section of code, this wont normally affect threading or your RPM display, as it is updated too fast for you to see , but that simple noise spike can make the program "think" that the RPM has slowed by 50% or more for just 1/25000th of a second, a fraction later the system will see the rpm is not really reduced.

  Im pretty sure this is what caused the error, and weve fixed it so it will be out within a day or two I suspect, next version you see anyway will have the fix. Dont focus too highly on the 50% thing, internally its more than possibel for it to occur with no spindle slowdown that YOU see, but the driver may have seen several, it takes steps to reduce noise and youd enever see the slowdown.

thx
Art
 
Re: Problems threading on the lathe
« Reply #144 on: March 17, 2009, 12:39:29 PM »
Great news, looking forward to trying the fix  ;D

Offline ART

*
  • *
  •  1,698 1,698
  • Tough as soggy paper.
    • View Profile
Re: Problems threading on the lathe
« Reply #145 on: March 17, 2009, 01:45:34 PM »
Hi Guys:

  I think that fix is on the web. Im pretty sure thios one shoudl fix you up, but Im still looking into
other possabilities. Ill have a test driver ready soon if this doesnt fix it so we can test deeper now
 that Im on the right track at the very least. So if you still see this X motion, yell and Ill send you a special driver
to help track down the exact position of the problem.

Art

Offline RICH

*
  • *
  •  7,361 7,361
    • View Profile
Re: Problems threading on the lathe
« Reply #146 on: March 17, 2009, 03:50:40 PM »
Art,
Thanks for the prompt attention on the threading.  :)

A little off thread here, but since manny users use backlash compensation,
can you guys take a look at the backlash problem in Mach. Hopefully that will
be even easier.  ;)

RICH

Offline ART

*
  • *
  •  1,698 1,698
  • Tough as soggy paper.
    • View Profile
Re: Problems threading on the lathe
« Reply #147 on: March 17, 2009, 04:14:35 PM »
Rich:

  Im not aware there is any issue with BL, works fine last I tested it. Not my baliwick anyway though..
Art

Offline RICH

*
  • *
  •  7,361 7,361
    • View Profile
Re: Problems threading on the lathe
« Reply #148 on: March 17, 2009, 07:22:18 PM »
ART,
Is it Brians?

Here is the link to the thread i started.
Real pain in the neck, and if coupled with threading can be confusing.
Simply put, it is a shuttle accel value issue.

http://www.machsupport.com/forum/index.php/topic,10855.0.html

RICH

Offline RICH

*
  • *
  •  7,361 7,361
    • View Profile
Re: Problems threading on the lathe
« Reply #149 on: March 17, 2009, 07:56:00 PM »
Hi All,
Has anyone tried the latest version 3.042.023?

I still get the same XZ move and now there are actualy "two" of them instead of
only one. That was with G32 and using the SS.

Art, send me the special driver when you get it done.

RICH