I am trying to use my CNC and Forge to make something!
I want to engrave something and then cut it out on the CNC
Because the accuracy is + or - 1/4" on the CNC, no matter what I do, I can’t align the piece to CNC properly. Has anyone else had this problem?
I don’t have a cnc, but is there any reason you couldn’t do it the other way around?
Cut it out on the cnc first, then use that file with artwork in place to make a jig out of cardboard for the glowforge.
Pin the cardboard down on the honeycomb, make the outside cut (with artwork ignored), then remove the cardboard cutout, put your cut piece in place, ignore the cut line and turn on your engrave? I use that method for other things.
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My workflow. Happy to add details if needed.
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Lay out design with registration marks at each corner (using vector program of choice).
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Google “registration marks”
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Use lower left as X,Y zero point (in CAM package or choice)
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Zero out CNC against that (lower left X,Y)
Tip: Use tabs to keep milled piece attached to original board (so you don’t loose registration marks).
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After machining, place the piece in Glowforge.
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Upload design and ensure registration marks match.
Tip: I typically mask my piece and do a very, very light burn over registration marks first (marking sure not to burn though masking). This ensures everything will be aligned. The camera will get you close but may not match completely. Trust the test burns.
I’ve also used the tip mentioned above and use a piece of cardboard as a template to help with alignment. Works great.
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Can you share a photo of what you are trying to accomplish - a failed project for example. If the community sees the level of detail and the shape of the files, perhaps someone could be more helpful.
In general, I would agree with the suggestion to CNC first and then engrave since the Glowforge can achieve quite precise alignment in my experience.
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Okay, there is something very wrong here and we want to help but need details.
Any decent cnc should be giving you accuracy and precision in the 1000ths.
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My X-Carve does not have ability to place material to the same level of precision as my Glowforge. It’s just not built for it, but there are “upgrades” or “additions” to get it there. As it comes, it uses simple microswitches to detect the limits of travel.
It’s never been an issue because I don’t need that kind of precision for material placement, but if you do, I’m sure whatever CNC you have supports those kinds of upgrades. I’ve never hear of one that doesn’t.
If I were using both machines for a single product, I’d probably go the other way - CNC first, then in the GF, where I can align using its camera.
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It’s not my CNC machine that’s off, it’s the Forge. My CNC is dead on with every cut. My problem is when I put the project I cut with the CNC and try to engrave on the piece, the design is off by about 1/8". I did a calibration, used set focus, drew an X and tried to line it up on the X and when I press ready, the focus moves that 1/8" and the engrave is off.
If your image is moving after you hit print, you need to use the set focus tool before finalizing your art placement.
Micro switches are horrid for repeat zeroing. If you don’t have a tap off block a sheet of office paper and some know how can get things closer than you can see in wood.
You need to search the forum for instructions on how to make an alignment jig. The GF camera is not accurate enough for anything but the roughest alignments. It can’t be. It’s connected to the cover and the cover’s alignment changes a little every time you open/close it.
If you make a jig, your alignment will be perfect and you won’t need to even look at the camera image.
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While I agree that a jig is often the best route I need to point out that there is a alignment procedure that will often bring a glowforge back to sub millimeter alignment. You can find it from the GFUI by going to the support page.
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The problem is that you cannot rely on the calibration remaining at sub millimeter alignment. It will move (if it was truly a constant, the factory calibration would still be fine, you wouldn’t need to recalibrate). You won’t know it has moved until it ruins something you assumed was going to be correctly aligned.
If you make a jig, you can never go wrong, and you don’t have to waste time going through the tedious camera alignment procedure every time the cover shifts because you closed it harder than intended, or the chassis twists a bit because you bumped the machine, and the camera’s alignment changes…
My camera was perfectly aligned once. When its alignment changed, I just stopped using the camera for anything except rough alignment. A jig is less effort by far than recalibrating. And I am a fundamentally lazy person. 
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Thanks for all the suggestions. I was able to figure it out, but using a jig didn’t work for me, because of the thickness of the material. I did however use a 3/4" piece of mdf and then laid out my project on that and drew some reference lines on it. I got within a bit less than a 1/16", which for that project worked just fine.
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