Author Topic: Trying out drawing on paper with my CNC. I can't seem to get CB to work.  (Read 3497 times)

Offline huntleybill

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SO I downloaded this .jpg and I want to draw this using my CNC with a sharpie. Within CB, I Draw, surface, from bitmap. Then set the x/y size and create surface.

I then do an edit, surface, silhouette. and clean up and stuff I don't want.

With the .jpg I get a bunch of squiggly lines instead of the lines that show in the image. In hopes of fixing this, I open inkscape and do a trace image, remove the background and it exports the file in .png format. All looks fine. I then go back to CB and draw a surface from bitmap but nothing shows in the screen. It's a big empty!

What am I doing wrong here? Can someone kindly explain how I can take a drawing and set it up to draw it out on my CNC? I attached the files for your review.

Thank you for your help
Bill

Offline Bubba

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #1 on: December 04, 2019, 01:47:49 am »
Once you trace it in Inkscape, Save As Desktop Cutting Plotter. Dxf format and open it in CB.
My 2ยข

Win 10 64 bit, CB [1.0} rc 1 64 bit, Mach3, ESS, G540

Offline dh42

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #2 on: December 04, 2019, 02:31:56 am »
Hello

If you're using CB v1.0, you can also "digitize" the picture in CamBam (I assume it's what you're calling "trace" in Inkscape)

http://www.cambam.info/doc/dw/1.0.0/cad/bitmap.html

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David

Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #3 on: December 04, 2019, 02:37:53 am »
Thank you Bubba. That worked. Now every line is a spline. Is that ok or do I need to convert everything over to polylines?

Offline dh42

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #4 on: December 04, 2019, 02:49:12 am »
The way with CamBam V1.0

https://www.screencast.com/t/NQ2hUhUQc8rY

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David

Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #5 on: December 04, 2019, 03:10:17 am »
Thanks guys. I did all the steps. converted to polylines, but when I go to do the MOP, I can't generate a toolpath or produce g-code. I notices that when I get object extremas, the Z is 0. Is this why?

I tried resizing and setting Z to 1mm but that didn't change anything.

Offline dh42

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #6 on: December 04, 2019, 03:28:30 am »
Quote
I notices that when I get object extremas, the Z is 0. Is this why?

Yes, it's a normal things ; a 2D drawing has no "depth" ;)

Quote
but when I go to do the MOP, I can't generate a toolpath or produce g-code

What kind of mop are you trying to use ?

Please share your .cb file ;)

bed time for me ...  ;)

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David

Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #7 on: December 04, 2019, 03:48:17 am »
I was using the engrave MOP. I didn't know what else to use for this applications. File attached.

Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #8 on: December 04, 2019, 03:56:17 am »
I also tried V-engrave and profile MOPs. The file that is saved is still empty and no toolpath.

Offline Mark81

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #9 on: December 04, 2019, 04:12:26 am »
I was using the engrave MOP. I didn't know what else to use for this applications. File attached.

The file has no MOP.
I suggest to start with some basic tutorial, and read the documentation.

Anyway, if you want to engrave along the lines the Engrave MOP seems the right guess ;D
In general, you have to change at least the following default values according to your machine, tool, stock, etc...:

  • Clearance place: to avoid collisions to any object on the working area
  • Depth increment: the Depth Of Cut
  • Stock surface: the (Z) point of contact between the tool and the stock
  • Target depth: the depth of the desired (final) cut
  • Cut/Plunge feedrate: how fast you want to cut/plunge
  • Spindle speed: if you have the control of the spindle speed
  • Tool diameter/number: to set the current tool you're using

If I understand correctly you want to "draw" the picture using a marker.
So you can just set something like this:

  • Clearance place: 10 mm
  • Depth increment: 0 mm
  • Stock surface: 0 mm
  • Target depth: -0.1 mm
  • Cut/Plunge feedrate: give it a try but begin quite slow (i.e. 600 mm/m)
  • Tool diameter/number: 1, 1 (it's always a good idea to set them)

Basically you can zero you Z-axis when the pen barely touch the sheet. The MOP will "engrave" at 0.1 mm below. Of course you can adjust these parameters according to your marker and the final result.



Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #10 on: December 04, 2019, 04:31:55 am »
Thank you Mark. I did have an MOP set with most of the settings you had suggested. I tried a V-engrave, an engrave, and a profile MOP. None of these would produce a toolpath or a file that my software (UCCNC) would show something to "mill".

YOur understanding is correct. I am attempting to "draw" on paper with a Sharpie. I though that the "engrave" MOP would work best for this type of file.

Try the file yourself. Let me know if you get something different. I know I must be missing something. CB has always worked for me before.

Offline EddyCurrent

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #11 on: December 04, 2019, 08:25:34 am »
Bill,

How can it go so wrong ? :D try the attached cb file.

1. Engrave is the only MOP to use for this application so forget about any other.
2. Make sure you have the correct post processor selected for your machine
I used the 'Default' one in the atached file, you may have to change it.
3. Choose a tool with a tip size similar to the drawing pen, 1mm would do for this job
4. Use a target depth like Mark suggested of -0.1mm
5. Use a Depth increment of the same value, 0.1mm
« Last Edit: December 04, 2019, 09:49:43 am by EddyCurrent »
Made in England

Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #12 on: December 04, 2019, 21:09:25 pm »
Success!!!!! Thank you Eddy. although I'm not sure why it didn't work for me as I used the same MOP with almost the same settings (depth increments and target depths were set to 1 and -1 respectively) and plane was set at 3 instead of 10 but I am not sure either of those settings are critical to it not working.

Maybe downloading your file Eddy, showed MY file what it was supposed to do and then it did it!

HOWEVER... just one more detail. If you notice in the original picture the eye brows, nose, mouth, etc are colored in. When converting the file to .dxf to import into CB, it creates the lines but does not "close" those areas so I can "pocket" and fill in those areas (or color them in with the sharpie).

I am not sure if this is outside of what CB is designed to do, but can anyone recommend how to get the file to work such that I can fill in those areas? If it is outside of what CB can do, can you recommend a software that can reproduce the image and still work with CB?

Please don't say Vectra Aspire or such software as I am not going to spend $2000 US per year for occasional use.

Thank you again all.
Bill

Offline ubiquity

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #13 on: December 04, 2019, 21:16:34 pm »
This is an extremely valuable thread/topic - can virtually be used as a tutorial for using CamBam as a drawing tool.

@dh42 - the Trace process in Inkscape produces vector paths for most clearly defined lines in a raster image (usually based on a threshold contrast between the line and its surroundings). Results for shaded areas are somewhat less predictable.

For those unfamiliar with Inkscape it is an open source (and free) vector drawing and illustration program available for all three major platforms Linux, MacOS and Windows.

Offline huntleybill

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Re: Trying out drawing on paper with my CNC. I can't seem to get CB to work.
« Reply #14 on: December 04, 2019, 21:23:23 pm »
I would be thrilled to have this used as a tutorial for others. I would even volunteer to write these steps up from start to finish so everyone can benefit. I would really like to figure out first how to re-create the infill just like the original picture has first.
« Last Edit: December 04, 2019, 21:27:49 pm by huntleybill »