Messages

61

General Mach Discussion / Re: Limitations of PC Parrallel Port

« on: June 20, 2009, 10:22:49 AM »

Thanks for the link Rich!  I'll definitely be getting in touch with Bill!

62

General Mach Discussion / Re: Limitations of PC Parrallel Port

« on: June 19, 2009, 04:35:11 PM »

I was not aware that you could tailor CV mode.  I will have to search on that subject to see what I can find out.  My guess at this point is that I WILL use CV mode, but keep my feedrates low to minimize it's affects.

You're both correct.  At some point I'll have to "just do it".  I just wanted to take advantage of the knowledge and experience in this forum and not "reinvent the wheel".

Thanks again to both of you!!!!!!!

63

General Mach Discussion / Re: Limitations of PC Parrallel Port

« on: June 19, 2009, 12:37:11 PM »

Thanks guys! 

Great feedback, but, guess what?  It generates more questions.

Back to my intention for this machine.  I'm looking for the greatest accuracy I can get for my pool cue inlays.  The more precise the fit, the less likely it will be that you will see the "glue lines" around the inlay.  In the research I've done so far, I read that Constant Velocity mode may create "rounded corners".  This would be unacceptable, so I was thinking I would use Exact Stop mode.  However, I agree with simpson36 that this would potentially cause "burning" due to the zero chip load during the exact stop.  In addition, Hood makes the statement "using Exact Stop which would put more strain on the hardware".  So now I'm torn on what mode to use.

So here's my questions.  Can you elaborate on the "strain on the hardware" statement when using Exact Stop mode.  I can understand the strain on the hardware during high speed start/stop operation.  Since cycle time is not a priority for me, would this statement still be true if I tuned my motors for a relatively slow rapid rate?  Conversely, can I eliminate the "corner rounding" aspect of Constant Velocity mode by setting my acceleration as high as possible?

64

General Mach Discussion / Re: Limitations of PC Parrallel Port

« on: June 18, 2009, 01:50:35 PM »

Thanks for the reply simpson36!  You confirmed my guess about the pulse rate.

As for the acceleration, I need to ask again.  I am familiar with the concept of "work hardening" from my machinist days (years ago).  I should have given more information or asked the question differently.  I will mainly be cutting wood (pool cue inlays) and the occasional piece of plastic or aluminum (fixtures/jigs).  I'm not a production shop, so cycle time is not my main concern.  I'm more concerned with the hightest level of accuracy and longest life (least wear-and-tear) I can obtain with the machine. My question about acceleration was more "what's best for the machine".  Could too slow an acceleration perhaps actually be bad for the motors?

65

General Mach Discussion / Re: Limitations of PC Parrallel Port

« on: June 18, 2009, 09:53:09 AM »

I'm a relative newbie and I'm still learning. I've been reading this (and similar) threads and I want to make sure I understand something.  Is speed of axis travel the only reason to increase the Pulse Frequency/Kernel Speed setting?  

I followed the Tutorial Video and set mine at 25,000 and things seem to work fine.  Is there any downside to having this setting too low (other than limiting max speed)? I'd like to understand the implications (pro/con) of increasing/decreasing this setting?

That also brings up the topic of motor tuning.  I have my accelleration ramping up very gradually to make my moves as smooth as possible.  Same question here.  Is there any downside to having your acceleration set too slow?

66

General Mach Discussion / Re: Loading the Gecko G540 XML file

« on: June 03, 2009, 05:03:02 PM »

Thanks Hood!  I'll probably go with the Gecko 540 XML and start over with the modifications to create my own unique profile.  I hate to have to redo the work I've done so far, but it's better than having some obscure parameter set wrong and then wondering why the thing doesn't work.

I will look into that XML viewer that you mentioned. Manually comparing files is kind of tedious, but it's better than nothing

Thanks again!

67

General Mach Discussion / Re: Interface question

« on: June 03, 2009, 10:25:24 AM »

I have always wondered what they are for myself as they never seem to correspond to my settings
 In reality I would have thought there should only be 17 LEDs there as there are only 12 Outputs and 5 Inputs, the rest being Gnd, hopefully someone will know.
Hood

Wow!  I stump one of the experts!

All in jest Hood.

68

General Mach Discussion / Re: Interface question

« on: June 03, 2009, 09:38:14 AM »

I almost forgot.  I was curious about the Diagnostics screen too.  It has led's for the port pins, but there are only 24 led's.  There are 25 pins on the port.  Which pin is missing?

69

General Mach Discussion / Re: Interface question

« on: June 03, 2009, 08:34:07 AM »

Thanks guys!

I was pretty sure that it was a combination of version differences and my lack of experience with the interface.  I just wanted to check with the more experienced users to verify that I hadn't stumbled on a known problem.  It is good to know that changing screens while in cut is not a good idea.  I had assumed that the code priority would have simply prevented the screen change if it would affect the machining process.  For example, I believe that is the case when trying to update the Tool Path view itself when "In Cycle".  You have to "Feed Hold" before you can update that display.

One thing for Chip.  I'm not sure you understood my question about the "limit display".  I have "soft limits" defined and the table limit lines display fine in "Table View".  It's in the "Part View" that I was talking about.  In the tutorial, there is a box (red lines) displayed around the extremes of the part program coordinates.  In my display, only the left and bottom lines of this box are displayed (not a full box).

I was a software developer and I know (from experience) that the documentation is always behind the code

I'll just have to keep "playing" with the application. 

Thanks again for your replies!

70

General Mach Discussion / Interface question

« on: June 02, 2009, 03:28:46 PM »

I recently downloaded the latest lockdown version of Mach 3 (3.042.20).  I've been playing with it to get familiar with the interface before I connect my machine and controller.  So far I've noticed two things that don't jive with the tutorial videos that I've watched.

1) When the first gcode program, the tool display does NOT show a red box around the part drawing (showing part limits).  Instead, there are red lines on two sides only (X minus side and Y minus side of the display).

2) When a program is running, the tutorials said that clicking in the tool path display will remove the highlighted lines that show previous program moves so you can clean up the display.  When I click in the display, nothing happens.  I have to change the view (tool to table and then back to tool) to get it to clean up the display.

I may find more differences as I continue to "play" with the software. Are these just differences in how the latest version works (compared to whatever version was used for the tutorial), or do I have problems with my install of Mach?

One other thing happened that disturbed me.  While running a part that contained G2/G3 arcs, I was switching back and forth between the Program Run screen and the Tool Path screens.  On one occasion, after switching screens, an arc cut continued cutting off the part rather than transitioning into the next arc.  I have not been able to reproduce this, but it worries me a great deal!