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Thinking about this:
- This will be great for aligning cuts to printed material (paper cutouts, etc .). Assuming a pair of ‘snap marks’ on both a print and in a design give you orientation and scale, automatically correcting for positioning, scaling during printing, etc.?
- And shouldn’t aligning to snap marks automatically correct for distortion from material thickness? Admittedly paper is very thin, but (for example) paper mounted to draft board has a thickness.
- Shouldn’t it be possible to use the head camera to “zoom in” on an area and precisely position an engrave/cut, without ‘snap marks’? I’m imagining that you could roughly position the cut on the lid camera scan, then click a ‘Zoom In’ tool and click a position, then the head moves there and takes a picture of the position using the head camera, then you can drag your cut on that picture to exactly where you want it.
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This ^ is the most interesting piece of this for me. I’m selling a couple products that are produced in exactly this way and I’ve made my own jigs/systems to make all of this work thus far. Really would love to see tighter accuracies in placement.
While I’d love the functionality for free, I would consider paying for it. My ultimate consideration would be am I able to sell my product at the price point I need while covering the cost of the feature.
Really hoping I can get access to this!
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This is a great feature. I got to see it in action at @cynd11’s. Still, I don’t see it as a replacement for normal camera accuracy to be able to use small bits and pieces on the fly as I was about to do with Zatochi. Might help here and there in connection with a jig. I was so spoiled with that unit’s camera placement accuracy.
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This has been done. So far the trick has been in printing snapmarks with printing technology that the glowforge identifies as snapmarks. I don’t know about today’s inkjets and laser printers, but fifteen years ago if you printed a dimensioned drawing on anything but a plotter, the dimensions were not true, just more or less relatively true. Also, line widths need to be controlled.
You can write algorithms to correct for these problems, but as fiducial marks are not a goal or promise of glowforge, why should they put in the time? Putting in the time to identify ones made by the glowforge laser is a step along the path to true pass through functionality and supposedly perfect camera preview placement. No time wasted. Doing it for pre-printed snapmarks, is something I personally would prefer they don’t do at this time.
It does this to at least some degree. I have a jig for cheap ceramic tile and the tile is thicker than the cardboard of the jig. I was entering entering one height or the other and it was behaving just fine. These were multi-step engraves (as in engrave the tile, remove, engrave the next part, remove, engrave the next part) with pixels in the png bumping up against each other and the laser seemed to be spot on.
I was also entering .250" for .172" material, because I hadn’t measured the material sold to me as quarter-inch until I was trying to troubleshoot something else. It didn’t have any alignment issues it didn’t have when the correct height was entered.
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Every laser printer I’ve ever used (back to at least 1996) has been extremely accurate. (Admittedly I’ve never used any super cheap consumer models, but anything running actual Postscript should be spot-on.)
As for cheap inkjet printers, who knows, but I imagine the vast majority of them are quite accurate these days.
As long as you’re using proper design software, that is. Something like Word will move stuff around on you, but that’s not the printer’s fault.
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With the correct settings Word isn’t WYSIWYG.
I don’t recall the software, but it was professional drafting software. Rather than do the math to figure out an implied dimension I used a caliper and then thought, nope that ain’t right. So I did the math. Then I re-measued, thinking well, maybe outside line, or something I wasn’t getting, but I could not make the repeated measurements from the paper and what the math said the dimension was add up. So I tried other measurments, the same issue. Then I asked an engineer on the project and he told me about the no guarantees. Maybe it was the drafting software shrinking down what would have been a full sheet of paper to 8.5x11 that was the root cause, but it always came out right on a plotter (albeit on a proper sized sheet of paper.)
I’ve never had a problem with scale on printed material, either at home on my laser printer or on my professional printers at work. The trick is, in the example you gave, that someone clicked the “scale to fit” button, and you should never do that with engineering drawings. If you print you should print to a specific scale. Even Acrobat/Bluebeam have options to print at no scale or specific scales.
My issue with printing to sticker paper and then lasering is that there is no guarantee that the paper will enter the roller system exactly straight, nor is there a guarantee that the paper is “precisely” 8.5"x11" or that any corner of the paper is exactly square. Snapmarks remove that as a problem.
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this. even on a 75k color copier, true page registration can be sketchy at best. you have to bump up to something like an HP Indigo, which is significantly larger (and more expensive, and uses liquid toner) to get really good digital page registration. or go offset.
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The snap marks don’t need to be that precisely printed, I wouldn’t think - they just need to be recognizable patterns, and with a distinct point that can be identified (e.g. a center of the cross-hairs). If there are two snap marks in a print, and two matching snap marks in an SVG loaded to cut, then the SVG can be scaled and oriented such that the center of the two cross-hairs match between the SVG and the print. From the math, if an image were printed out at some random scale and orientation, it should still work fine - it all comes down to translation to make one point match, and rotate and scale to get the second point to match.
BTW: The new Snapmarks are just the GF logo. They no longer include the cross.
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Well yes, registration is always a problem. Where something is relative to the edge of the paper may be off, but all the things printed on the page should be correct relative to each other.
Reminds me of certain camera-based laser cutter, actually…
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I am curious if they did enable job scaling via snapmark scaling. All I know for sure that has been tested is position and rotation.
Height is already measured pretty accurately with the red dot laser, which fires when checking snapmarks to ensure that the system knows precisely how far away the mark is. So that shouldn’t be needed from snapmarks (and you cannot use the size of the snapmark to figure out both material height AND job scaling at the same time anyway)
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If your goal is to match fiducial marks. For pass through functionality, as it is promoted, I believe their goal is to match any part of a design, where any part could look a lot like another part and be anywhere on the bed. In this use case, the balancing act between perfect and close enough would seem to shift towards the perfect end. It can’t be too close to perfect, or you’ll search forever, but I believe it has to be a good ways away from the close enough you need for defined fiducial marks.
You’re right - I was only thinking about matching cuts to prints. For aligning cuts when material is moved through the Pro pass-through I’d think they would need to have the material area covered with marks (e.g. like the Shaper Origin ‘domino’ tape, though hopefully with fewer marks) so that wherever the material is pushed to, the software can figure out where the material is. In theory the marks could be engraved by the laser on unused areas in each area that is cut, so that they could be seen and referenced on the adjacent cut, but I’m not sure how the software could automatically figure out which parts are unused. Perhaps the designer could sprinkle marks around the the design in order to make it GlowForge-ready?
This is a feature I really need for some of the projects I want to do. I am designing overlay templates for keyboards and audio controllers. Cutting these out accurately has been challenging.
Those Snapmarks are stinkin’ adorable ;p
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My guess is that they want to avoid any registration marks. It can be done, but the challenges they have to overcome are daunting.
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Honestly this is the only reason I’ve tried to use my GF in months. Lack of accurate visual alignment means the GF isn’t very useful to me for lots of the things I want to be doing with a laser, so Snapmark is something I’ll be looking for in GFUI (not there yet.)
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That’s almost precisely the whole reason I bought a GF. I’m looking forward to being able to use the GF for the projects I originally had in mind. Here’s hoping.
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