Feature request: Absolute positioning - CNC Mill style

I already filed this will support:

So coming from the CAD/CAM world, 3D printing and CNC Machining, the glowforge has some weird bed-locating behavior. Yes, it is really cool to throw some wood or acrylic in and drag a job to match wherever you put your piece.

But for repeated work jobs (say dog tags, where I might build a jig to hold 10 of them perfectly aligned to the bed, then have a document where I have 10 text blobs to engrave on them) I want to be able to hard-specify the origin point and dimensions. In other words I want to have a document that has templates on it where you specify the bottom left of the bed to a known point (yes I realize the GF bed is not as solidly held like a CNC wasteboard is but it should be pretty precise ā€“ or at least as good as optically dragging on a web page!).

Then when you load the job there would be a checkbox with ā€œSet to known 0,0 originā€ or something that would fix the jobs to be identically placed.

This would allow batch workflows with high precision.@Dan can we load this into the hopper?

As an example from the CNC world, when I got my PocketNC CNC mill, they also include a fusion 360 model of the bed/vice so you place everything relative to that in your modeling, and then you know exactly where in real-space your job will machine.

There are ways to work around this, but this would make way more sense for repeated jobs.

38 Likes

Been a lot of talk and requests about this with confusing responses from GF and endless workaround suggestionsā€¦

Seems like the great camera feature has some limitations in this regard. Though there are probably ample ways to solve it.

I agree 100% that this simple function should be absolute base line.

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While I agree with the request, just makes sense to me, but Iā€™m no engineer :smile: , I know the best sounding work around right now sounds like making sure your jig fills the whole bed and make sure your file youā€™re cutting does the same. In that scenario the positions should be absolute between cuts at least ā€“ granted all this is just stuff Iā€™ve gleaned from reading posts, so there is no practical knowledge here at all :stuck_out_tongue: Someday soon I hope to test my theoriesā€¦Bwahahaha (hear thunder and lighting in the background)

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Isnā€™t that basically done by shoving your jig into a corner and specā€™ing your file to the bed size?

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At least for me the file is not being positioned reliably. Even large jobs are sort of stuck in the top right, and donā€™t appear to line up correctly. Remember line up within thousandths of an inch is what we need. And a jig only works if you can realign to the jig, which so far I have not reliably been able to do (havenā€™t even cut yet with this since on screen you can see you arenā€™t perfectly aligned)

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As I recall, thereā€™s a ā€œfix,ā€ where if you size your file to match the full size of the bed, the Forge will reliably preposition the artwork where it was before. @takitus will tell you more.

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Yes, please!!! As a CNC user who is used to having things placed just so, I would give this all of my likes if I could!

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Totally agree this should be included!
Just curious as I mostly am a CAD guy, does AI and other 2D vector programs have a 0,0 like cad?
Iā€™m assuming no???

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As for positioning in the workspace? AI does. You can choose one of 9-registration points for the object and then place it. You can also drag your rulers out to set 0,0 wherever you want in the document.

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Ive been asking for this from day one, loudly and often. The 20x12 artboard hack helps a little in this respect, but numeric positioning, scaling, and rotation should all be included in the UI. Having to bounce back and forth to AI over and over in 20x12 mode, saving, re-uploading, etc is not the optimal solution.

I struggle with this almost EVERY TIME I use the laser. Ive lost a lot of materials to being unable to know where my object was placed in the UI, how big/small it was scaled to, and how much it had been rotated.

Its SUCH a headache to deal with not having this feature, and would be so easy to add. Ive looked at the code. Please add this.

some of my begging:

A little bit of give:

A start, but we def need true numeric control, and 0,0.

This whole post started by @Duality has a lot of back and forth on it, definitely worth a read and bump:

and heres the little mockup of the fiducial homing square I posted on that thread that we could use as a dynamic home if they were able to use the head cam to get really tight accuracy.

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@henryhbk

If you make an illustrator file with a 20x12 artboard, wherever you place your objects in that file will be where they are on the bed. I dont think this is a good final solution, but will help a little in making repeated objects.

I made a tutorial post about it:

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I think people who are not used to machines donā€™t appreciate the importance of this (and seemingly nor does GF). But the lack of a known 0,0 and relying on an ā€˜aim & shootā€™ methodology will cost a bunch of ā€˜mis-printsā€™ / material waste eventually for people.

Thanks for pushing it @takitusā€¦ Iā€™m with you all the way.

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I totally understand the simplicity of the drag and drop and I think this makes the most sense for the bulk of their target market, HOWEVER, a sizable chunk of their market, especially the pre-release sales are probably makers and an absolute zero is just gonna make sense to them and it does seem like it would be strait forward to implement, even if it is just an option in the settings.

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I donā€™t know if there will ever be a 0,0 on the bed because the head is homed to the camera and there are no limit switches on the axes. How accurate are the lid hinges? Are they completely free of play so the camera always has a repeatable position relative to the bed?

I would prefer that the cameras find the work piece corners and automatically align the artwork to those by translating to the centre and rotating, plus an option to stretch to fill. I think this is far more in keeping with Glowforgeā€™s way of doing things and is a actually a lot better than using jigs and having a 0,0. Also if you really must use a jig to position parts you should be able to drop it in anywhere and have the cameras centre your artwork relative to the corners of the jig.

So I donā€™t think it should be CNC style, it should be an advance that gives the same end result more easily.

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My rule of thumb for this is if I can take the jig and everything out of the laser, put it back in, and it can cut the exact same line/pattern, then its working as it should. If you cant, then its not.

I tried this on the last batch procedure I did and it didnt turn out well. The jig/svg I made allowed me to make exact copies every time, even after closing the browser, but once I removed the physical pieces of the bed/jig and put them back in, the alignment was off, and by quite a bit due to the amount of play the bed has. This should really have a more solid fixed position.

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This is bad news for any sort of jig/fixture solution we dream up.

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What if you donā€™t have a 90 degree corner? (Iā€™m thinking circles, triangles, and using leftover scrap that will be in who-knows-what kind of shape)

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I need to take a very close look tonight at the innards, and see if I can 3D print a jig holder that grabs onto something more solid than those divots the bed sits in which I can use as a registration point. Glad you mentioned this, as I was sort of planning originally to fix the jig to the honeycomb with pins, like I can do on the wasteboard of my X-carve, but if I can make this work, I will share the file.

Which CAD do you use?

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I totally see your point, but its fun to be an old curmudgeon too :slight_smile: Guess its sort of like the no head phone jack in the new iphone (sigh)

You would think with the # of sensors in this thing you could get a repeatable position

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The laser is absolutely capable of absolute precision with insane accuracy. Thatā€™s not the problem, it is that the bed can move slightly (unlike a CNC mill where the wasteboard is part of the frame) and so the 0,0 as is doesnā€™t reliably translate to accurate placement. As I mention above, let me see if I can 3D print something tonight.

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