Topics

1

General Mach Discussion / Tool Offset and Home Z questions

« on: January 16, 2009, 07:37:08 PM »

Hi Everybody,
2 questions:
1.) When I press Go To Z, the first thing that happens is that the Z axis drops down, and then the x and y run. This means that if I have made some change to the z height during a project, the tool bit gets dragged across the material, or worse. Is there any way to have the Z axis operate after the machine gets to x and y zero?
2.) Is x and y zero at the edge of the tool bit, or the center. In other words, when I specify 000 Home, should the bit's center be pointing at the cross hairs of x and y, or should I allow for the bit radius?
Thanks again, Bob

2

General Mach Discussion / Inaccurate routing

« on: January 11, 2009, 10:37:27 PM »

Man, is there anybody who has as much trouble as I do? I spend more time on the forum that I do cutting. Here's my latest issue: I ran a test cut on 2 identical ovals, doing a profile on one and a pocket on the other. I wanted to see how closely the profile piece would fit into the pocket. The answer was, not very well. The profile fit into the pocket with about 1/8th inch of gap on one end, and the gap was not symmetrical. In other words, both cuts were not perfect ovals, even though they were designed in VCarvePro, not some design I imported into VCP, and one was an exact copy of the other. The ovals were only 3" x 4", so an 1/8th inch gap is huge for that size job.
My machine is tight and there are no loose screws, bearings, etc. I have anti-backlash lead nuts, and I was running very slow and cutting not very deep into soft material. To retest, I cut a 2" square and got similar poor results. Anybody have any ideas of what it could be?
Thanks again, Bob

3

General Mach Discussion / Screen question

« on: January 09, 2009, 11:50:54 PM »

Hi all,
Hope everyone had a great holiday, but it's time to get back to the grind stone and answer some more dumb questions! Here's my latest: When I activate the little jog screen, its left side covers the last 2 numbers of the DROs that are shown in the middle of the work screen. All other pages fit fine. Anyone?
Thanks, Bob

4

General Mach Discussion / Buzzing steppers

« on: January 03, 2009, 05:38:24 PM »

The latest puzzle....my y and z stepper motors seem to work ok when they are following Gcode but I can't jog with them -- they just give off a loud buzzing noise. Anyone know what the cause might be?
Thanks, Bob

5

General Mach Discussion / License not activated?

« on: December 31, 2008, 06:40:58 PM »

I have discovered, I think, why my router runs for a few minutes and then stops....since it stops on Gcode line #499, and since everything after that is repeated, I suspect that my license has not been activated. I went through the normal set up procedure when I got my license, so can one of the moderators let me know what I should do now? Also, I have spent several weeks getting my settings dialed in -- can my license be activated w/out losing them?
Thanks, Bob

6

General Mach Discussion / Error messages

« on: December 28, 2008, 10:59:32 PM »

Am having 2 error messages I don't understand:
1.) When I try to run a project I get an immediate Limit Switch Triggered message, and even though I have set up the limit switch override, when I Reset the error message keeps coming back. This happens in spite of the fact that I'm nowhere near a limit switch, and I can jog everywhere without it happening;
2.) Interspersed with the Limit Switch Triggered messages noted above, I'm getting Too Fast for Pulley...Using Max. messages. I'm using a 1/8th inch bit @ 20,000 RPM, only cutting .05 into the material, which is soft plywood, and running at 30 inches per minute. How could that be too fast for a pulley, and how would Mach know how much stress is on the pulleys in the first place?
Thanks again, Bob

7

General Mach Discussion / 2 Questions

« on: December 25, 2008, 08:22:43 PM »

I was trying to run a test prior to cutting my first piece and I realize that I don't understand HOME. I figured I would design a small 3" x 5" rectangle, jog to the middle of the table and run the file in the air w/out the router on, but when I got there and tried to change the X, Y, and Z absolute home zero to that new location, I couldn't do it. I first clicked Machine Coordinates, then zeroed the axes, then clicked Ref All Home, but the Abnormal Condition light started blinking and when I checked the Diagnostics Page I found that the old home position hadn't changed. What should I have done?
Also, whenever I close Mach 3 I get a Fixture Save? query, even when I haven't loaded a Gcode file. What kind of fixture are they referring to?
Thanks again, Bob

8

General Mach Discussion / ports and pins

« on: December 18, 2008, 10:05:56 PM »

School goes on.....I have a home built all-leadscrew 3-axis 24" x 48" cnc router w/ Xylotex steppers and I just bought an optical breakout board through which I want to run limit switches. I have wired all the switches together using the NC (normally closed) pin, put 5 VDC through the switches, and hooked it to opening #15 on the board. I then went to the ports and pins input section and activated the x, y, and z plus and minuses, and entered pin #15 for all of them. When I turn everything on and trip a limit switch, nothing happens and none of the LEDs light up on the diagnostics page. Anyone know what I'm doing wrong?
Also, when I use VCarvePro to calculate a toolpath, it asks me what version of Mach 3 I want to use for the postprocessor, and it has 4 choices (Mach 3 Arcs, Mach 3 Line, etc.) How do I know which version I have?
Thanx again, Bob

9

General Mach Discussion / Soft Limits

« on: November 18, 2008, 07:23:51 PM »

OK, I totally don't understand the soft limit setup. If I define my XY work space as a 22" x 44" area that has limit switches 2" outside of that, and the Y axis has a 7" height with 1" to the limit switches above and below that, and I want to have soft limits 1" outside my XY work area and 1/2" above and below my Y, with a slow down setting of 1/2", shouldn't my Soft Limits settings be:
X Soft Max: 45
X Soft Min: -1
X Slow Zone: .5
Y Soft Max: 23
Y Soft Min: -1
Y Slow Zone: .5
Z Soft Max: -7-1/2
Z Soft Min: +.5
Z Slow Zone: .5
When I do this, I can still jog right past all of the soft limits. And, what is Home Off.? And also the manual says, "the defined limits only apply when switched on using the Soft Limits toggle button -- see Limits and Miscellaneous control family for details." Where the heck is that??? Anybody?
Thanks again, Bob

10

General Mach Discussion / soft limits

« on: November 17, 2008, 04:15:00 PM »

Question re: soft limits and home. Why not have soft limits 1 inch from home and slow down 1/2 inch from home, with mechanical limit switches 2 inches from home (and the opposite of home)? That way you could go home without triggering any slow down, but a runaway would be slowed down and stopped before it could do any damage. Also, is there a Go Home button somewhere on one of the screens?
Thanks, Bob