picture to engraving?

[hoagiem]

i am fairly new to the cad/cam world and have a few questions if somebody wouldn't mind helping out. i have been seeing alot of photo to engraving articles out there lately. i understand that the photo will have to be scanned into some type of software and then converted to g-code eventually. my question is this: what software, or packages are necessary to perform this operation? how does this work, as in: scan to what type of file, convert to what type of file and then .... eventually load and run on a cnc machine?

there seems to be, in my mind anyway, a large cloud that the photo goes into and the engraving pops out the other side. could someone put this in laymans terms, kind of an engraving for dummies format?

thanks for the help.

mark

[ger21]

If the photo is in jpg or bmp format, you can get g-code from Mach2/3, http://www.artofcnc.ca or use something like MeshCAM, http://www.grzsoftware.com

[miljnor]

Ive actually been meaning to ask a similar question.

I know there are programs to make this happen but I am curious as to how they determine what is 3d and what is flat from the photo???

Is this something that the user has to determine and enter values or is it something better like the software determines from the shadows how far away and what the curvature is??? (doubtfull but hopefull)

[ger21]

Usually you convert the photo to grayscale, and the depth is determined by the shades of gray, with black usually being the deepest. Depending on the software, you may be able to skip the grayscale conversion. For best results, the photo's may need to be edited a bit.

[Aksess]

step #1 scan picture around 300 dpi with scanner.
Step #2 save scan as jpg or bmp
Step #3 edit picture as needed like removing background, lightning, removing red eye etc
Step #4 convert jpg to a grey 8 bit pgm file using pic to pic a free program
Step #5 get imagecarve open the pgm and sellect the size and depth of cut usually .030 works beautiful.
Step #6 click the convert button in imagecarve
Step #7 run g-code

Like I say if anyone needs help with imagecarve I will be glad to help you achieve results you are looking for!
Proof is in the pudding look at some of my pictures I have carved.

[hoagiem]

thanks aksess, that is exactly the kind of info i was looking for, straightforward and to the point. i appreciate it.

[dcarr]

There are three basic approaches to engraving images.

1. Draw (engrave) outlines or contour lines from the image.
This is sort of like tracing the things in the picture to produce a line drawing, and then running an engraving bit along those lines. VS3D can do automatic tracing (contouring) by using the image brightness levels as if they were Z heights in a topographic model. I'm not sure if other programs do that.

2. Draw (engrave) dots or pixels from the image.
For example, take a flat piece of aluminum with a black anodized coating. Use a pogo-stick ("peck") type of tool path with a V-bit. The depth of each "peck" is determined by the brightness of the image at that point. Each peck is spaced far enough from the other pecks such that, at least, a small amount of black remains in between. The result is that brighter pixels in the image come out as larger (brighter) dots in the engraved piece. Because a wide V-bit is used, and the depth is determined by the pixel brightness, the amount of exposed bright aluminum is larger for bright pixels. So what you end up with is what looks like (from a distance) a grainy B&W photo. VS3D can do this. I'm not sure about other programs.

3. Carve a continuous surface based upon the image brightness levels.
This is what is done in the VS3D Image Embossing/Carving tutorial:
http://www.designscomputed.com/vs3d/...mg_emboss.html
This technique is what most of the "Image Engraving" software programs do.

Where VS3D surpasses the other programs is that VS3D has sculpting tools to modify the surface. For example, suppose you wanted to carve a picture of someone in relief, like the face on a coin. You start out with a digital photograph of the person and map image brightness to surface height. At this point, the only thing many other software programs can do is output the G-Code or whatever to cut it. But suppose the person had dark-colored hair. Because the surface comes from image brightness, their eyebrows will be sunken deep into their forehead. VS3D has the sculpting tools to allow the eyebrow areas to be lifted and blended to make the surface look better. Yes, you could use PhotoShop or whatever to "lighten" up the eyebrows before importing the image. But it can be hard to predict if the results, when converted to a relief surface, would look good or not. In VS3D, you do the sculpting on the surface, so you always see what the true 3D surface really looks like.

PS:
Please excuse the "hype" - I developed the VS3D software, so naturally I'm a bit biased

[Jason Marsha]

dcarr,
I am checking your link out and your software is quite impressive.

Jason

[Aksess]

VS3D looks ok what is the total machinging time and cutting speed used on the girl carving? Tool changing time included.

[dcarr]

Originally Posted by Aksess VS3D looks ok what is the total machinging time and cutting speed used on the girl carving? Tool changing time included.

The piece shown was done using a 60 degree V-bit (no tool changes required). First pass was a horizontal traversal (uni-directional "climb" cut). Second pass was a vertical traversal (alternating direction). The second pass wasn't really necessary, as it turns out. The results after the first pass were good and the second pass provided only a minimal amount of cleanup.

step-over spacing - 0.025"
XY jog rate - 3"/sec.
Z jog rate - 2"/sec.
XY feed rate - 2"/sec.
Z plunge rate - 1"/sec.
material - MDF board

Total time for the first pass was about 14 minutes.
The second pass was less than that because it cut in alternating directions (much less jogging than the first pass).

This was basically the first attempt at this piece, and the chosen speeds were probably slower than optimal.

[doroteo]

what kind of cnc machine was used for the girl portrait ?

[dcarr]

Originally Posted by doroteo what kind of cnc machine was used for the girl portrait ?

I have an S&W Engineering CNC machine. But the girl photo as shown carved in wood was done on a Shopbot router (the VS3D software has ShopBot output as well as G-Code).