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Nick Marchesani
09-02-2020, 6:16 PM
Is it possible to make the laser engrave the white areas of a black and white vector image instead of engraving the black areas?

If so how?

Thanks!

Kev Williams
09-02-2020, 6:51 PM
That can't be done by the laser itself, it needs help from you :) --if you WERE to engrave the white to black, that would include all the background, and would go to infinity... So what you need to do is create a border around the graphics.
this is an example- the top 2 are positive and negative, below each is the wireframe versions of each:
440243
The right versions are the originals-
the lower left, you'll notice one extra outline that I added. That's all there is to it!

it DOES get tricky to accomplish this with more complex shapes, but it's do-able.
In EzCad, the 'edit' tab, there's an 'offset' function, with options-- If what you're offsetting is grouped,
it will offset all outlines and in-lines. If you ungroup vectors, you can offset individual lines...

Nick Marchesani
09-02-2020, 7:26 PM
That can't be done by the laser itself, it needs help from you :) --if you WERE to engrave the white to black, that would include all the background, and would go to infinity... So what you need to do is create a border around the graphics.
this is an example- the top 2 are positive and negative, below each is the wireframe versions of each:
440243
The right versions are the originals-
the lower left, you'll notice one extra outline that I added. That's all there is to it!

it DOES get tricky to accomplish this with more complex shapes, but it's do-able.
In EzCad, the 'edit' tab, there's an 'offset' function, with options-- If what you're offsetting is grouped,
it will offset all outlines and in-lines. If you ungroup vectors, you can offset individual lines...
oh boy! What am I getting myself into? Lol! I'm going to try but I'm not so sure that it can be done with the attached image?

Kev Williams
09-02-2020, 8:22 PM
piece o' cake with that graphic, assuming it's vector lines. If it's a bitmap, your only option is to negative the image, but that will engrave the entire background.

If it IS vector lines, then- if you've hatch filled anything, un-hatch. Box the entire graphic to group it all, then UN-group it. NOTE THE GROUP-UNGROUP icons, sometimes it takes more than one un-group to ungroup it all. If part of it is still grouped, both icons will be red. If so, just hit the un-group button again until one button is gray.

Click on just the outermost outline. Click the edit tab, click the offset option... choose to NOT delete the original, and uncheck 'offset inside' as you want an outside offset -- set the offset .25mm to start, you can undo and re-enter if it's too much or too little. Just be sure to click the outline before choosing the offset option! (if you choose offset with no graphic line(s) chosen it goes into a different mode that I haven't figured out yet!)

Anyway- one the extra outline is created, box the whole thing and group it all, and hatch fill it. It will reverse like my example did...

Steve Utick
09-03-2020, 8:24 AM
Piece of cake, as Kev said, vectorize it if it's not, and do an offset if needed.

440283

Nick Marchesani
09-03-2020, 3:57 PM
piece o' cake with that graphic, assuming it's vector lines. If it's a bitmap, your only option is to negative the image, but that will engrave the entire background.

If it IS vector lines, then- if you've hatch filled anything, un-hatch. Box the entire graphic to group it all, then UN-group it. NOTE THE GROUP-UNGROUP icons, sometimes it takes more than one un-group to ungroup it all. If part of it is still grouped, both icons will be red. If so, just hit the un-group button again until one button is gray.

Click on just the outermost outline. Click the edit tab, click the offset option... choose to NOT delete the original, and uncheck 'offset inside' as you want an outside offset -- set the offset .25mm to start, you can undo and re-enter if it's too much or too little. Just be sure to click the outline before choosing the offset option! (if you choose offset with no graphic line(s) chosen it goes into a different mode that I haven't figured out yet!)

Anyway- one the extra outline is created, box the whole thing and group it all, and hatch fill it. It will reverse like my example did...
It worked as you said! I would have never figured that out on my own. With so many people buying lasers you should make a video training series. I would buy it!
Thanks Again!
Nick