Messages

871

General Mach Discussion / Re: Whose Fault Is ThIs?

« on: November 30, 2009, 01:37:49 PM »

OK, Brian has just confirmed this *is* a bug in the Mach3 CV code, and he's working on a fix.  As for my situation, if I go to exact stop mode, the problem goes away.  Since I'm not doing 3D profiling, this shouldn't cause me any significant grief, so I'm off to make some chips.

Regards,
Ray L.

872

General Mach Discussion / Re: Whose Fault Is ThIs?

« on: November 30, 2009, 11:44:51 AM »

Looks like this IS a Mach3 bug.  Brian has just sent me a test version that will hopefully fix it.

Regards,
Ray L.

873

General Mach Discussion / Re: acceleration

« on: November 29, 2009, 11:20:27 PM »

Hello,
Can anyone tell me if a high acceleration will reduce your accuracy. my vol is set at 300 and my acceleration is set to 5 but it is slow moving but if i set it to 30 it moves great. If I set it to 80 it slides my machine back and forth when it moves. I would like to keep it at 30 if i t doesn't hurt the accuracy.
Thanks,
Jeff

At some point, you'll start losing position if you go too high on acceleration.  The loss may occur on rapids, or during cutting, depending on the characteristics of your motors.  It will also make the machine shake more on starts, stops, and changes of direction.  There's really no advantage to very high acceleration, unless you're doing a lot of 3D profiling, or running at very high feed rates.  Just find a value where the response is "crisp", without excessive shaking.

Regards,
Ray L.

874

General Mach Discussion / Re: another parallel port question

« on: November 29, 2009, 10:15:47 PM »

Pins 1, 14, 16, and 17 are all available as outputs in Mach3.  Pins 10, 11, 12, 13 and 15 are available as inputs.

875

General Mach Discussion / Re: Whose Fault Is ThIs?

« on: November 29, 2009, 10:08:10 PM »

Chip,

I don't understand what that changes.  The knee will rapid all day long at 50 IPM with no problems. and the fault is occurring on the first and third G03 moves of each set, never on a single axis move.  X and Y rapid at 200 IPM, and also have never lost position.  What would those F10s accomplish?

Regards,
Ray L.

876

General Mach Discussion / Re: Whose Fault Is ThIs?

« on: November 29, 2009, 09:15:37 PM »

Hi, Ray

Post the G code your having problems with for a start.

Chip

Chip,

Here's one example.  The faults occur *only* on the 3-axis helical moves, yet I can take those lines, and run them over and over with no problems at all.  It's only when run *with* the preceding moves that the fault occurs.

(Filename: Mount Plate Ramped.tng)
(Post processor: My Mach2 Post 090819.scpost)
(Date: 11/29/2009)
G20 (Units: Inches)
G40 G90
F10
(Part: Fixture Plate)
()
(Process: Spiral pocket, Lower Support Shaft Bore, T145: 1/2 Carbide, uncoated, 3-Flute, Aluminum Cutter, 1XSlotting [145], 0.52 in Deep)
G00 Z1.5000
(1/2 Carbide, uncoated, 3-Flute, Aluminum Cutter, 1XSlotting [145])
M06 T1 G43 H1 (1/2 Carbide, uncoated, 3-Flute, Aluminum Cutter, 1XSlotting [145])
G00 Z1.5000
M00 ( Pulley: 4 Motor: H )
M966 P8
M03 S6120 (Spindle CW 6120 RPM)
M07 (Mist coolant on)
G00 X27.6000 Y9.1579
G00 Z0.0197
G01 Z0.0000 F4.896 S6120
G03 X27.8421 Y9.3947 Z-0.3750 I0.0000 J0.2421
G03 X27.6000 Y9.1579 I-0.2421 J0.0053 F29.376
G03 X27.7365 Y9.2000 Z-0.5200 I0.0000 J0.2421 F4.896
G03 X27.7365 Y9.2000 I-0.1365 J0.2000 F29.376
G00 Z1.5000
()
(Process: Spiral pocket, Lower Retainer Shaft Bore, T145: 1/2 Carbide, uncoated, 3-Flute, Aluminum Cutter, 1XSlotting [145], 0.52 in Deep)
G00 X27.8000 Y5.4579
G00 Z0.0197
G01 Z0.0000 F4.896
G03 X28.0421 Y5.6947 Z-0.3750 I0.0000 J0.2421
G03 X27.8000 Y5.4579 I-0.2421 J0.0053 F29.376
G03 X27.9365 Y5.5000 Z-0.5200 I0.0000 J0.2421 F4.896
G03 X27.9365 Y5.5000 I-0.1365 J0.2000 F29.376
G00 Z1.5000
()

Regards,
Ray L.

877

General Mach Discussion / Whose Fault Is ThIs?

« on: November 29, 2009, 08:51:05 PM »

Today I ran into a new problem....  I started using ramping to start cuts - this typically means a 3-axis helical move.  But, on some of them, my Z axis servo is faulting!  If I run the offending lines in isolation, they NEVER fault, even when run repeatedly.  Also, if I reduce the X/Y acceleration to what the Z axis is set to, the problem also goes away.  I've been using this machine for over a year, and NEVER had a servo fault, except when I accidentally ran an axis into a hard stop.  I've also verified the supply voltage is holding well, never dropping more than about 1.5V from its nominal value.  I'm suspecting perhaps Mach3 or the SS is not respecting the MUCH lower acceleration setting for the Z axis when entering the 3-axis moves, as the fault occurs almost instantly, before the Z axis has moved hardly at all.

How do I find and fix the cause of this so I can get back to work??

Regards,
Ray L.

878

General Mach Discussion / Re: Need help with motor tuning!!

« on: November 29, 2009, 10:57:53 AM »

Thanks Ray, I went ahead and boosted it up to 35 ipm and ran a few programs in the air, and it seemed to do ok, I will try some more in the morning, what do you think I can expect for speed?

Walt

Walt,

No clue.  That depends on your motors, controllers, power supply, reducers, screws, how tight your gibs are, and all kind of other factors.  Every machine is different.

Regards,
Ray L.

879

General Mach Discussion / Re: Need help with motor tuning!!

« on: November 29, 2009, 12:10:07 AM »

I would suggest you leave acceleration low, and increase velocity, and see how high you can push it without stalling.  When you reach the speed where it stalls, back off by 30%, then start increasing acceleration until it starts stalling, and when you reach that point, back off 30%.  After that, it's just a matter of running it enough to make sure it's reliable under real world conditions.

Regards,
Ray L.

880

General Mach Discussion / Re: Laser pointers to set starting mill position

« on: November 28, 2009, 08:58:54 PM »

Zarzul is a member of the forums here. Here is where you should start.....

http://www.machsupport.com/forum/index.php/topic,5004.0.html
or
http://www.wildhorse-innovations.com/

That probe is available for only $100 from Arnie Minear, who actually manufactures them.  You can contact him at  aminear@wyomingwireless.com

Regards,
Ray L.