Problem with Vcarve toolpath

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MarkJohnston
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Problem with Vcarve toolpath

Post by MarkJohnston »

I'm having trouble setting the right depth for a VCarve toolpath. I'm carving a company's logo on a bulletin board and the first one came out prefect. The board is 4 foot high by 3 foot wide so the logo is pretty big. When I set up to run number two the VCarve was much too deep. I don't think I changed anything but at this point I've tried about everything I can think of and can't make it come out right.

I'm using a CMT Vbit 60 deg angle and I've double checked the tool information and it looks good. I've used this tool a lot before without any problems. I got the start depth on the toolpath at 0.0 and I normally set the flat depth at .06 and its cutting to .14, way too deep. The preview shows that it will cut at .06 like the setting when I put the cursor over one of the cut areas. I'm running Mach3 and the Mach3 screen says the Z is at .06 when its running but it's cutting much deeper. The Z zero is set at the top of the board and I've checked it very carefully several places on the board and it seems fine. I ran a test setting the toolpath flat depth at .01 and the preview hardly shows up but when I run it the depth is about .10, an improvement but still too deep. I don't know what else I can change to fix the problem.

When I look at the G-code the Z setting is what the Aspire program says it should be.

Could there be a problem with my machine?

I'm suppose to deliver the boards on Monday which of course is par for the course.

Can anyone help.

Mark
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Firestone mockup actual run (800x560).jpg

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zeeway
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Re: Problem with Vcarve toolpath

Post by zeeway »

Seems to me, since you ran the file before and did not change it (right?), and it was good, the problem is not in the toolpath.

Things to check:
1. Is the material bowed up or simply thicker at the place the logo was carved - compared to where you zeroed the bit. ? This would make it carve deeper.
2. Is your v-bit moving in the collet?
3. Is your z-axis losing position on the frequent up movements? You can check this after running a file, to see if the bit comes back to the same z zero you started with. Also check for a slipping coupling on your z axis.

If worst comes to worst, you could do a simple oval inlay with the logo on it to correct for previous problems.

Good luck,

Angie

CoReForm3d

Re: Problem with Vcarve toolpath

Post by CoReForm3d »

Hi Mark,

I'll second Angie.

You can also try a manual move on the Z axis and check if the actual displacement meets Mach3 information.

If 2) in Angie's list is the problem, the depth of carving will probably not be constant, despite of the flat depth.

Try also restarting the PC (not only Mach3) and turn the machine electronics for at least 30s.

No more ideas, as I have no knowledge of Mach3.

HTH

____

All the best,

Didier

MarkJohnston
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Re: Problem with Vcarve toolpath

Post by MarkJohnston »

Thanks Angie for your comments.

I'm using 1/2" Oak plywood with an MDF core and it looks like it's laying very flat. I can't push it down or get any play in the middle. I wrapped the edges with solid Oak 3/4" wide and used biscuits all around after it comes off the machine.

The vbit is spinning and carving nicely just to deep.

I was watching the Z axis as it was running and once the Z goes down it doesn't move any deeper and until the next letter. After it stops it returns to the proper place and if I press go to zero it is perfect.

Didier: I didn't try to reboot but I turned the machine off so I will try it again, thanks for your comments.

Mark

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zeeway
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Re: Problem with Vcarve toolpath

Post by zeeway »

Just one more shot - check in Mach 3 that an offset didn't sneak in there for the z height. I don't know any way that could happen accidentally...but just to make sure.

Angie

dond52
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Re: Problem with Vcarve toolpath

Post by dond52 »

I use Mach 3 all the time. I can run a program perfectly one day and the next day it gets me.
When setting tool heights, I call all of my tools "Tool 1" . When I restart Mach 3 and set a
tool height I "SOMETIMES" forget to select "Tool 1" . Mach 3 starts up with " Tool 0".
When I forget to change the tool in Mach3 it is reading the tool height for "tool 0" when
I think it should be reading "Tool 1". SOMETIMES I get lucky and it will machine
above the part and other times I am not so lucky.

MarkJohnston
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Re: Problem with Vcarve toolpath

Post by MarkJohnston »

Angie: I'm not sure where that setting is in Mach. I haven't messed with that since I got the machine 2 1/2 years ago. I have the machine running now trying to finish this job. I changed the flat depth setting from .06 to .01 and it's carving about .04 so that's ok for now. Once this job is finished I will play around and see if I can find out what's going on. If you can will you send a picture of where that setting is in Mach. If not I will investigate the documentation anyway thanks again for the help.

dond52: I don't have a ATC so I never mess with the tool number but when I checked the program that I'm running all the tools are set to tool 2 not 1. I don't know how I managed to change that. I will definitely change it back to tool 1 and see if that makes a difference. Thanks for the help.

Mark

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zeeway
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Re: Problem with Vcarve toolpath

Post by zeeway »

Mark - glad to hear you are kinda running.

I use the Blue Screen for Mach 3 - the offsets are shown in the Offset Screen - one of the screen choices along the top (see below).

Angie
BlueScreen.JPG

MarkJohnston
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Re: Problem with Vcarve toolpath

Post by MarkJohnston »

First of all thanks to all of you that have offered support. I think that is the best thing about the CAMaster and Vectric forum. When you have a problem sometimes you feel very alone with it in your shop until you get on the forum and people start offering advice. That makes me feel good and I usually start to relax a little and tackle the problem and feel like people have your back.

I just finished cutting the job I was working on and I'm in the finishing stage now. I still don't have a definitive answer why my machine is cutting deeper than the program says it should but by adjusting the depth less than I wanted I was able to sneak up on the proper depth. I even fixed the one that cut to deep and will give it to my customer as a bonus, it looks pretty good to. I will post some pictures next week before I deliver them. I really want to learn more about Mach3 and see if I can make some adjustments there that might help. I normally don't do a lot of work of sale but this job landed in my lap from a friend. If they like the product they may want me to make 160 of them one for each of their branches.

Angie: Thanks for the screen shot of Mach3. I have the original program and screen and haven't updated to the blue screen. Do you like the changes and think it's worth the update? Is it easier to use? Where do you get it?

Mark

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zeeway
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Re: Problem with Vcarve toolpath

Post by zeeway »

MarkJohnston wrote:
Angie: Thanks for the screen shot of Mach3. I have the original program and screen and haven't updated to the blue screen. Do you like the changes and think it's worth the update? Is it easier to use? Where do you get it?

Mark
Mark,

Glad to hear your job is coming our well. I read somewhere the other day, the definition of a craftsman is someone who can recover from his mistakes...

Yes, I find the blue screen less cluttered and easier to work with. I use the Mach Blue Probing Screenset by Big Tex from:

http://www.machsupport.com/screens.php

There are others there you may want to check out as well. The price ranges on these range from very small to free.

Angie

MarkJohnston
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Re: Problem with Vcarve toolpath

Post by MarkJohnston »

zeeway wrote:
MarkJohnston wrote:
Angie: Thanks for the screen shot of Mach3. I have the original program and screen and haven't updated to the blue screen. Do you like the changes and think it's worth the update? Is it easier to use? Where do you get it?

Mark
Mark,

Glad to hear your job is coming our well. I read somewhere the other day, the definition of a craftsman is someone who can recover from his mistakes...

Yes, I find the blue screen less cluttered and easier to work with. I use the Mach Blue Probing Screenset by Big Tex from:


Angie,

I guess I must be a craftsman then because if there's any way to make a mistake I will find it every time at least twice. :lol:

Mark

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Re: Problem with Vcarve toolpath

Post by Leo »

Mark,

Exactly - how - do you set the "Z" on your tools in your machine.

I suspect there is a problem there.
Imagine the Possibilities of a Creative mind, combined with the functionality of CNC

MarkJohnston
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Re: Problem with Vcarve toolpath

Post by MarkJohnston »

Hi Leo,

I do two different methods for setting the Z. I use a touch plate which I have checked with a micrometer and set up in Mach3 or I manually lower the Z to touch on a piece of note book paper that's .0025 thick, the paper will drag on the bit but not rib or cut into it.

I haven't had a problem with that in the past but I'm not really sure at this point what is causing it. Thanks for your interest.

I've made 3 of these boards so far with a little different finish on each so they can decide what they want.

Mark
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