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Smokey930
09-19-2018, 11:22 PM
I have finished up, or very close, few odds and ends to do, a new diy build....I've got all my axis operating well except when I try to cut z always plunges into the material right at first and stops the whole show. When I first started trying to cut the machine did cut the gcode but at about 1/4 of the size it was supposed to be. So I then found that I needed to calibrate steps/inch or scale the axis on each axis which I know have done through the use of Mach 3. I'm zeroing to the surface of the material each time using Mach 3......when I intentionally zero Z to 3 or 4 inches above the table and run gcode, the spindle plunges down then raises back up and begins as if its cutting material...I don't know if this is in the gcode or Do I need to set some offsets for tool differential? and I also read something about a G28 setting which i'm not far enough along to understand what that is other than it has to do Z starting movement/position.....any help would be appreciated, Thanks

Jim Dawson
09-20-2018, 12:04 AM
Can you post your G code, just the first 20 lines or so lines should do.

Smokey930
09-20-2018, 12:53 AM
I would be glad to, but how do I do that?....when i'm in mach3 I can see the gcode but haven't found a place to view it in vcarve…..in a text editor of some sort?

Smokey930
09-20-2018, 01:15 AM
G90
G0 X0.0000 Y0.0000 Z1.5500
(SBULLDOG8)
T1
(V-BIT {90 deg 0.5"})
F100.0
F30.0
S16000
G0 X1.9979 Y2.5338 Z0.9500
G1 Z0.5700 F30.0
G1 X2.0042 Y2.5296 F100.0
G1 X2.0042 Y2.5708
G1 X1.9655 Y2.5566
G1 X1.9979 Y2.5338
G1 X1.9923 Y2.5256
G1 X2.0411 Y2.4934
G1 X2.0070 Y2.5430
G1 X1.9787 Y2.5881
G1 X1.9506 Y2.5552
G1 X1.9923 Y2.5256


THATS THE FIRST 20 LINES OF GCODE FROM VCARVE


























































]

Jim Dawson
09-20-2018, 01:29 AM
What is the Z position before you start the run? It looks like Z should moving down correctly.

Smokey930
09-20-2018, 02:07 AM
TO THIS POINT I HAVE JUST ZERO'D THE X & Y AXIS TO THE BOTTOM LEFT CORNER OF THE MEDIA I'M WANTING TO CUT ON.....SO I HAVE BEEN ZEROING TO/OR JUST ABOVE THE SURFACE OF THE MATERIAL WITH THE Z...THATS WHAT MAKES ME THINK I'M NOT ACCOUNTING FOR THE BIT AND MAYBE I NEED TO SET A OFFSET...

Smokey930
09-20-2018, 02:09 AM
LOOKING AT THE CODE I CAN SEE THAT X & Y ARE SIMPLY COORDINATES....Z IS TO BUT VERTICALLY 1.55 INCHES ABOVE THE SURFACE? JUST ASKING...I ALWAYS FEEL THE MORE YOU UNDERSTAND THE MORE YOU CAN IMPROVE

Jim Dawson
09-20-2018, 02:12 AM
You need to zero the Z with the bit installed, in other words, Z zero is the tip of the tool bit. The top of the material is fine for Z zero.

Smokey930
09-20-2018, 02:18 AM
I have been zeroing z to the tip of the tool bit....that's whats got me stuck...from everything ive read that is an acceptable practice...but certainly isn't working

Jim Dawson
09-20-2018, 02:21 AM
LOOKING AT THE CODE I CAN SEE THAT X & Y ARE SIMPLY COORDINATES....Z IS TO BUT VERTICALLY 1.55 INCHES ABOVE THE SURFACE? JUST ASKING...I ALWAYS FEEL THE MORE YOU UNDERSTAND THE MORE YOU CAN IMPROVE

That's what the code reads. But first we need to understand why Z is diving down then going back up to start cutting. Z should move to 1.5500, then to 0.9500, then to 0.5700, always moving down.

Jim Dawson
09-20-2018, 02:26 AM
Is Z zero set to the top of the material in Vcarve?

Smokey930
09-20-2018, 02:26 AM
The last hurdle I was trying to get over was scaling the axis....I was at 1/16 and when I did the calibration on mach 3 I ended up with some crazy big numbers of steps to reach 1 to 1 to match the code that was being input...so i'm now at 1/8 and brought the steps down considerably, I thought that was the issue for a while, but now not so much

Smokey930
09-20-2018, 02:27 AM
So was typing the last issue......yes to the top of material in vcarve…….give me a few and i'll jump over there and verify that

Jim Dawson
09-20-2018, 02:32 AM
When you tell the Z to move 1 inch, does it actually move 1 inch?

Smokey930
09-20-2018, 02:32 AM
In vcarve it says Safe Z 0.2 X 0.0, Y 0.0 and Z 0.8

Smokey930
09-20-2018, 02:35 AM
yes, when I tell Z to move 1 inch it moves 1 inch......that was the pretty much the sum of the last mess....had to scale all the axis

Jim Dawson
09-20-2018, 02:36 AM
In vcarve it says Safe Z 0.2 X 0.0, Y 0.0 and Z 0.8


I'm not sure I understand what the Z 0.8 is

Smokey930
09-20-2018, 02:43 AM
Sorry for the delay apparently had a little glitch in service...……..In vcarve it says Safe Z 0.2
home position X 0,0, Y 0,0 AND Z 0.8

Smokey930
09-20-2018, 02:45 AM
WOW MY SYSTEM HAS LOST ITS MIND IT DIDN'T SHOW THAT THE LAST MSG'S WENT THROUGH SORRY FOR THE DUPLICATE.....WITH THE Z 0.8 TO ME THAT SAYS ITS STARTING OUT 0.8 OF A INCH BELOW THE SURFACE OF THE MATERIAL, BUT I HAVEN'T TOUCHED ANY OF THOSE SETTINGS...…..DOES THAT NEED TO BE CHANGED TO 0.0? AND CAN I DO THAT KIND OF EDIT IN MACH 3?

Jim Dawson
09-20-2018, 02:48 AM
Below the surface should be -0.8, positive numbers should be above the surface, negative numbers below

Smokey930
09-20-2018, 02:55 AM
OK I JUMPED BACK OVER INTO VCARVE AND IT SAYS 0.08, AND I WOULD AGREE IF ITS NEGATIVE ITS GOTTA BE DOWN AND POSITIVE UP ABOVE

Jim Dawson
09-20-2018, 02:59 AM
The best I can say right now is make sure the the top of the material is 0 in Vcarve. It's past my bedtime :)

Smokey930
09-20-2018, 03:03 AM
WAY PAST MINE TOO, I APPRECIATE THE INCITE

Smokey930
09-20-2018, 12:39 PM
Ok i'm still stuck.....I've tried messing with some of the z settngs in the programming process but am still clearly missing something...I thought perhaps i'd just do a simple gcode using text from vcarve….I used the word test and it did actually go into the wood, and cut but it cut some weird shape with a series of lines......what file type should I be taking to the cnc on the memory stick?......previously what I have been trying was .nc type...i'm just saving the toolpath after I do a design and that's what i'm taking to the cnc, should I be taking the .crv file?

Jim Dawson
09-20-2018, 01:25 PM
Mach3 should be happy with a .nc file. The code snippet you posted looked like it should work with Mach3. You can attach the whole G code file to a post if you change the extension to .txt. It really is just a text file anyway. I'll take a look at the file and see what it looks like in a viewer.

Smokey930
09-20-2018, 03:37 PM
ok here's the gcode….

Smokey930
09-20-2018, 03:41 PM
I just almost feel like it's a setting of some type that I haven't done right, because I've tried other files and they all have the same behavior...the bit will dive into the wood a little bit then lift up and it will be trying to do the cutting about half a inch or so above the surface of the material. its like I don't have some type of parameter set right

Jim Dawson
09-20-2018, 04:52 PM
A half inch above the material is what the G code shows. I'm not sure what is causing the tool to dive to about zero, that's not in the G code. But Z0.5700 is where Vcarve is telling it to go. It looks like Vcarve thinks the top of the material is above 0.5700, maybe around 0.9500?

Smokey930
09-20-2018, 05:56 PM
well that makes since, and ideas how to fix this?

Jim Dawson
09-20-2018, 07:58 PM
I have never used Vcarve, but in general in any CAM program there is a way to set the working surface. I don't have time to download and learn Vcarve right now, but you might take a look at the online tutorials.

The tool diving down might be the Safe Z setting in Mach3. I think it should be a couple inches or more above the work. Maybe at the Z home position.

Smokey930
09-20-2018, 08:23 PM
that is funny I just completed a tutorial for making a small sign in vcarve and followed their every step so I could look at the gcode to see what it looks like compared to what I have produced....thanks for your time and help.....if I figure this out i'll post it back on this thread...