Messages

1

G-Code, CAD, and CAM discussions / Re: Mach3 adding extra loops in a string of arcs

« on: March 24, 2013, 08:54:13 AM »

Thanks for all the intense effort to attempt to get to the bottom of my original problem.  I've been running a number of new pickguard files using Conv. cutting path with no problems.
It's great to know there are so many experienced operators willing to help.
Terry, I can't help calling you "Rainman"  .  Thanks again.

2

G-Code, CAD, and CAM discussions / Re: Mach3 adding extra loops in a string of arcs

« on: February 16, 2013, 12:40:10 PM »

Thanks, BR549, I tried loading the latest rev of Mach 3, and ran the part (cutting air). It seemed to be fine, then I noticed I hadn't defined the tool 4 dia. After setting that to .125 dia. it was back to the same problem.
Tweakie, I attached a better screen shot, deleted most of the code so the portion of interest is larger so you can see the extra moves.  Looks like Mach is thinking each arc segment needs a lead-in move.  But why only these few segments and not the rest of the part outline?
Before the original post I tried several times re-drawing the arcs slightly different and re-posting the code. no change.
Will a Fanuc post processor work better? maybe I'll try that after the grandkids go home today.

3

G-Code, CAD, and CAM discussions / Re: Mach3 adding extra loops in a string of arcs

« on: February 15, 2013, 08:40:29 AM »

Thanks, BR549,
So, it's not Me? 
Is there a fix for that? does the latest rev. of Mach3 overcome that? I'll try that this afternoon for kicks.
I suppose if nothing else, I could skip over that section and run the cutter the other way w/ G2 arcs.  But why does it only do it on this part, this section of the outline and no others ( out of about a dozen similar part outlines)? I guess I just got lucky, eh?

On the other hand, there's a beautiful sunrise over the frozen lake this morning, life is good. 

4

G-Code, CAD, and CAM discussions / Re: Mach3 adding extra loops in a string of arcs

« on: February 14, 2013, 09:00:50 PM »

Thanks for the reply, Tweakie
I just ran the gcode again on the router, did a "z axis up" flyover to verify the tool path, and still get the wierd extra moves from about line 1220 to 1300.
Also checked the Mach3 version: R3.042.040
Thanks.

5

G-Code, CAD, and CAM discussions / Re: Mach3 adding extra loops in a string of arcs

« on: February 12, 2013, 01:13:02 PM »

Tweaky,
Sorry, I've been staring at that part so long I thought everyone could read my mind
The lower right large radius part outline is the area of interest.  The resolution is pretty poor, sorry, but if you can see the purple (actual part) is a smooth curve,
the tool path (white) is irregular.  I haven't cut material yet, just did a flyover run and noticed the extra moves, then looked closer at the tool path display to see the anomaly.

6

G-Code, CAD, and CAM discussions / Mach3 adding extra loops in a string of arcs

« on: February 12, 2013, 10:54:28 AM »

Any ideas why extra "hooks and loops" show up when routing a part outline consisting of a series of arcs? I've been routing about 15 or 20 different outlines
(guitar pickguards) successfully, then suddenly a new wrinkle shows up.  Cad files are created in Flexisign, (poly line curves) exported as .dxf, to BobCad,  .dwg, cleaned up to make arcs tangential and features more dimensionally correct, then BobCam to generate gcode with Mach3 post. 
I struggled through lots of learning re. lead-ins/-outs, and issues with tool path offsets (thanks to many good forum posts as resources)
I can't see any difference in the code from other parts of the same outline. I've zoomed in on the .dxf and .dwg drawings and can see no breaks or flaws in the joining of the arc endpoints. I've tried re-starting Mach, reloading code, re-creating code.  So far, it's the only drawing to show the problem.
I hope the attached files are enough info for a clear understanding. Thanks a bunch.

7

G-Code, CAD, and CAM discussions / Re: Newbie question on G-code looping (While, for, etc.)

« on: February 11, 2013, 08:10:22 AM »

Thanks, Graham and Dslicker, for your response. Sorry this is so long in coming, lots of distractions and a  death in the family changed the direction of my efforts for a time.  I have a new problem, but I think it needs to be posted in a different thread.  Thanks again.

8

General Mach Discussion / Re: G41 giving unexpected move

« on: December 04, 2012, 09:42:39 PM »

  It's a good thing I didn't see your last post before i tried it. It worked!  Essentially, I did what Gerry suggested, by figuring an (manually drawn) offset toolpath (arc w/ rad .0075) and G40, cutting w/ .0625 rad bit made a .140 hole.
But, for the part outline it ended up not closing the string. the last arc veered to the right and missed the start point of the first arc by the tool dia. x 2. I'll keep at it.
Thanks again.

9

General Mach Discussion / Re: G41 giving unexpected move

« on: December 04, 2012, 05:18:31 PM »

Thanks, BR549.  So, if I re specify the circles w/ a smaller dia. and G40 it should work.  I'll give it a go.

10

General Mach Discussion / G41 giving unexpected move

« on: December 04, 2012, 04:55:27 PM »

I'm trying to get my router to make .140 dia. holes with a .125 dia. bit.  Drawing is a .dxf imported into BobCad w/ Gcode generated after cleanup, tool dia is set in BobCad and G41 is automatically inserted.  the holes are drawn as .07 rad. arcs. I had problems with Mach3 making a few holes (out of about 18) correctly, but for the rest the machine makes a " J " or " S " shaped move or a larger dia. hole as if G41 is ignored (all arcs are CCW in direction on the drawing). The code looks the same for each hole (only location numbers for x and y change). I took the code and ran it through a gcode to dxf converter and it came out as a clean drawing, identical to the original.  I've tried many times re-generating the code in BobCad. each time a different hole (or holes) comes out correctly.  I havn't cut material yet, just a flyover to check the program.  I don't have much hair left.  The router works great using PhotVCarve.  One time I forgot to add a line for tool number so it made the tool path without an offset, the holes were all round but of course would have been too large.  when I added   M6 T4  it went back to the S or J motions for most of the holes.
There are 3 rectangles w/ large rad. corners that come out right w/ proper offset.  BTW, I'm trying to make a guitar pickguard.

Why the J or S moves?