Built one of polarbrainfreeze's cars

Continuing the discussion from 3 vehicle nearly-build from polarbrainfreeze:

Had a little help from the Shapiro twins. A few build notes:

  • The SVG lines aren’t connected, which means the laser doesn’t draw them in a smooth, continuous line. Maybe someday, but the current state of affairs is that it’ll do a little line somewhere, head off and do another little line, come back and do the next bit, etc. It’s so precise you don’t see the result at the end, but it’s a bit slower and somewhat maddening to watch.
  • I used a dye to do the flames, and it bled under the masking. Next time will use a paint.
  • My alignment was a bit off. I removed the pinholes Ben put in the design; I should have replaced them either with a slot and tab to align everything, or a jig to hold it square while gluing.
  • As a result, the wheels scraped. Darn.
  • I resized it to use a Q-tip shaft instead of a pencil, since that’s what we had around the office.

All in all, quite a hit with the kids! Thanks Ben.


It’s great to see it from the kid perspective!


I can’t wait to get this reaction out of my kids lol.


How does the GF software interpret line order? An epilog printer reads the vector lines and cuts them in order. It sounds like the unconnected lines in the SVGs you used were all out of order. Does GF have a tool to reorder vector lines in a file? If not, feature request! To be honest it’s a bad file and shouldn’t require adjustment in the GF software. Still, it’d be a convenient feature to avoid having to load it up in illustrator, fix all the issues, connect all the paths, and then re-export. Something like a checkbox for “continuous cuts through connected lines” that doesn’t switch off the beam as it transitions from one to the next.

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When did the ink go on? Does anyone think a deep score line would have prevented the bleeding?

Reminds me of the old “Kinder Surprise” toys we use to get up here before they made all their products safe. All it needs is a fly wheel and some small gears for it to fly forward


Not sure, as ink has less solids and so is much less viscous and better able to penetrate the grain.

Makes a very cool toy!


Very nice. Thanks for the build. But, oh, the digital age . . . Your office had Q-Tips, but NO pencils? :grin:


I’m OK with needing to join the lines in another program, but Illustrator does such a bad job of it I would also greatly prefer that the Glowforge software handles the joining task as well.

Maybe this is just another glaring example of my ignorance when it comes to Illustrator, but when I’ve joined a bunch of individual line segments in Illustrator I’ve found that it also adds a bunch of errant lines all over the place. I guess Illustrator hears the word “join” and figures you want your entire drawing to be one giant continuous loop. Why they would program it that way is completely beyond me. Inkscape is even worse. It seems that you have to select each joining point INDIVIDUALLY and join each one as a separate operation, which is completely absurd. At least Inkscape has the excuse of being a completely free piece of software. Rhino does the job perfectly (Open file > Ctrl A > join (done.)) but doesn’t open SVGs (which is surprising because being able to open/export every file type in the world is one of Rhino’s strong points).

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You don’t have to choose each set of points, but you do need to pick your battles :slight_smile:

If you select a single set of lines that make up a “closed” shape, then illustrator will join them without extra segments.

If you select lines that should not be contiguous (i.e. two shapes next to each other) then it will try to join them all together.


SVG is text, so it should be pretty easy to write a program that will join lines. You’d likely need some kind of tolerance for joining lines whose endpoints are close but not quite. And as long as you were only doing it for purposes of lasering, you wouldn’t have to worry about whether the resulting file was pretty or could be easily edited.

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Would only work for lines with terminators near one another. If you have the lines overlap for a distance, and want to join with removal of redundant line that wouldn’t work (pretty sure that wasn’t the case here though)

Which makes perfect sense - the software can’t know what your intention is in bringing together disparate lines/segments (as in: I want this circle to join with this box but the circle should cut into the box…no, I don’t want the circle cutting into the box, I want a box with a hemispherical bump on the top…). I’m okay with the line by line joins - that gives me control over what it’s doing so I know I’m getting what I want. AI allowing us to join the lines of a closed shape is handy but more gravy than meat as it were.

Fixing overlapping lines like that would require a different level of analysis. Definitely wouldn’t result in a file suitable for doing something else with. It would also make cutting-order decisions weird, because you’d have to decide which polygon the joined line was part of for cutting purposes. I’m not thinking this through carefully, and it seems it ought to be OK for things that are designed properly, but there would be some pathological cases that wouldn’t work well at all. (It’s OK-ish if one figure shares a line with another but doesn’t overlap it. I think. If there is overlap you would get weirdness. Say if you have a piece that shares a border with another but then has a protruding tab.)

I don’t think that makes any sense what-so-ever. Why would I want Illustrator to draw a line between two random vertices in two sets of line segments?

If I have two rectangles comprised of four individual line segments on opposite corners of the “artboard”, surely there’s a way to differentiate between the endpoints that are within one nanometer of each other and two (random) endpoints that are five centimeters from each other.

I’d love to hear the workflow that includes the need to join two disparate shapes together with a line where the placement of the line makes absolutely no difference to the designer.

It’s like the Adobe programmers didn’t realize the traveling salesman was drunk, but decided to follow him around anyway.

Perhaps I should have started a new thread about this. I’ll delete this post if a new thread is created.

Every tool has workflows that are unique to their intended function(s).
Illustrator was originally designed for, well, illustration, and the need to do what you are asking it to do is maybe not such a high priority.

Instead of selecting the entire drawing, just select one square. Then the join will work as you expect it to. I realize that is a pain when there are lots of squares, but if you really wanted to you could write a script to do it automatically.

The workaround of selecting all the individual shapes is obvious (even to me) but I guess if that’s the way it is that’s the way it is. I don’t know how to write Illustrator scripts and my desire to learn is low. :confused:

Complaining about it here probably won’t change anything though so I’ll bow out. I guess if I want to continue my crusade against Illustrator I’ll do it in another thread. Sorry for the interruption.

That look of awe is 90% of my reason for wanting a glowforge.


I can’t see any objects in your 2nd graphic that I’d ask AI to join for any reason or expect it to be able to do so either. Those are all pretty disparate boxes and lines. The wandering path is not unexpected at all. The use case doesn’t make sense so neither does the solution.

For your point & line example, I might want them joined as an object to create a barrier to a surrounding etch. In the case you showed - connect the point and the ends of the line to create a triangle. Use that to control an engrave - either engrave something outside the triangle within which I’ve embedded the triangle or engrave the triangle but not the external object.

Both use cases (yours and my response) are pretty arbitrary but that’s the result of not using real-life examples. I’ve not had an issue with AI or Corel’s ability to join what I wanted and didn’t find telling the software which parts to join very onerous.

What I would like from AI, and what @Hirudin may be wanting here as well (or not) is a “join overlapping anchor points” function that works for open shapes.

If I make a square using 4 single lines, use the Direct Selection tool to make a bounding box around the whole square, and then “Join”, AI connects each overlapping anchor point and creates a closed-path square. Good.

But if I only make three of the four lines, and do the same thing, AI does NOT join the three separate lines into a single path: i still have three separate paths (and two pairs of overlapping anchor points). I have to put the bounding box over each pair of overlapping anchor points individually and join them one at a time. Not good.

If there is a script, function, or method that I do not know, I sure would love to find out.