Trouble with alignment

So we make a lot of wooden discs and try to engrave a lot of circular images on these circular discs. We’ve consistently had the problem of the alignment being off 1/4 in or more some. It is very frustrating because it looks perfect on screen and then we run it and it is so off and the product looks tacky. Please help.

Support is going to want you to do a Gift of Good Measure on PG medium draftboard and upload a screenshot of the results that shows the design over the actual cut, along with the rulers, like I did here.

Just thought I’d let you know so you can speed up your response time. :slight_smile:

After you do the GOGM, here’s a post to read that might help you with keeping things lined up the way you want them:

this post seems to more be about lining up the images not the issue I’m having.

Maybe post some examples? I guess I’m not sure what you mean by “alignment,” if it’s not about lining things up. :slight_smile:

I meant that post is more about aligning several layers of an image. my GF alignment is the problem.

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Did you select the correct material before printing that Gift of Good Measure? It looks to me like it doesn’t know the material height. Otherwise, yeah, that’s way off!

yeah its perfect with medium draftboard as it should be, and it’s on the drop tray

yes, the camera looks tremendously out of focus. if you have the correct material selected, the cut lines on the surface of the material should not be that blurry.

I’m not a good judge of blurry, because mine’s insanely blurry (and headed back to the mother ship as a result), but at least my blur ends up about the same size as whatever I was cutting. :stuck_out_tongue_winking_eye: Definitely something not right, there…

Can you describe your procedure for engraving on a disc? I am still unsure if you’re having a technical problem, or experiencing the limitations of the camera.

Regardless of how good your camera is, if you really want to get that perfectly aligned, you should try making a jig by first cutting a hole in something the exact size of the disc and then using that to position it correctly for the engrave.

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Stuff like that, I usually just take a couple of quick measurements, create a corresponding shape in Illustrator, lay a piece of chipboard down and run a fast/low power score and set the object on that. Close enough for government work!

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Thank you for your patience. Along with our engineers I looked into the details of the Gift of Good Measure print, and we’ve found that the position of the crumb tray was not in the correct position compared to when it left the factory. Could you please double-check for any debris in the bed of the Glowforge, paying special attention to the dimples the crumb tray settles into? If your crumb tray is bent at all, please let us know this detail as well.

The discs we engrave on are too thick to use the crumb tray, but they sit 1.5 in below the camera so there is enough room. The PROBLEM is when it is aligned on my computer screen (with a jig and without) and I hit print, it comes out misaligned on my piece of wood. The image is circular and the wood is circular, but they never seem to align after I hit print.

The camera image is processed based on the material thickness you enter. If the surface of the material is not at the depth of the crumb tray + material thickness, then visual alignment will be significantly off.

Perhaps the disks are at the correct position relative to the camera, but I think Glowforge will want to rule out issues with the crumb tray as part of their diagnostic testing.

Better visual alignment helps but for great results, I echo other posters above and recommend creating a jig. You first cut a disk shape into a fixed sacrificial material, place the disk into the cutout, and then engrave. It’ll be perfectly positioned until the glowforge is powered off. After that you can either re-align the jig or make a new one. There’s an experimental feature slowly rolling out called “snapmarks” which can automatically re-align the jig… I haven’t gotten it yet but can’t wait.

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That’s exactly the thing that the link I gave you up above (“how to get perfect alignment”) addresses. Because of how the GF optics work, you’re never going to get exact alignment visually. You have to have other ways of doing it, and the post I linked to tells you how to make it happen.

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If the top of the disks is sitting 1.5" below the camera, there is no way on earth that the beam is going to be able to focus on it. So i’m not surprised that you are having alignment issues with those.

If you are cutting without the crumb tray, you have to prop the material up so that it falls into the correct engraving zone. The engraving zone is about half an inch from the top of the crumb tray down to where the surface of the crumb tray would be if it were in there.

Trying to engrave on an unsupported item is probably why the alignment is so far off on your lids.

The other thing that you have to do every time you try to engrave without the crumb tray is correctly calculate the “Thickness” of the material and enter it into the Unknown Materials slot. I have that highlighted because it’s not the actual thickness of the material that you will enter in this case, it is the thickness of the material that extends above approximately 1.4" as measured from the metal plate on the bottom of the machine.

The honeycomb surface of the tray is considered the zero point for focusing calculations. The laser can only focus correctly in the half inch range that runs from the top of the honeycomb and half an inch higher than that. So you prop the material up so that the top surface falls into that range, then subtract out 1.4" to get the correct thickness value for the Unknown Materials slot in the Thumbnail column.

There are a couple of very good tutorials here that explain what you have to do:

That’s part one.

The second issue that folks are trying to help you with has to do with achieving perfect alignment through use of a jig, instead of just trying to eyeball it. It is more accurate (100%) and taking the time to do it is going to be a real time saver for you if you have a lot of the same shape to engrave on…you just cut one jig hole, drop each lid into it, and engrave it perfectly. But it’s harder to do without the tray in place, you would need to prop the jig up as well. Maybe a small sheet of plywood propped up on scrap wood. As long as you do not move the jig or any of the images on the screen, it will engrave in the correct place.

But look at the tutorials for cutting without the crumb tray first…I think that might be the main problem here. You might get good enough results once you get the material into the correct range with the correct thickness listed to not have to mess with a jig. :slightly_smiling_face:

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We’d like to make sure your Glowforge is performing correctly with the crumb tray in while using Proofgrade materials. Since this problem is being seen on materials that were purchased from another company, we can’t offer support for prints that don’t come out as expected. However, once we make sure your Glowforge can print great on Proofgrade materials with Proofgrade settings, you should expect better results with other materials as well.

The software on your Glowforge is responsible for ensuring that the print lands on the material in the same place as the preview. When you’re done with a print, let a new image load. If the print appears on screen far from where it was supposed to go, you may have an alignment problem.

Most alignment problems come from the material being closer or farther from the camera than expected. While the software is still improving, you can take these steps for the most accurate alignment results:

  • Use Proofgrade™ materials.
  • If you don’t use Proofgrade materials, use a precision set of calipers to measure your material, and enter the thickness in the “uncertified materials” dialog.
  • Use material that is not warped or tilted.
  • Place your design near the center of the bed.
  • Clean the area underneath your crumb tray, particularly the four indentations on the floor.
  • Reboot the machine. Alignment can drift over time, particularly if you bump the head of your Glowforge while removing material.

Should you finish all of these steps, and find that you have an alignment error of more than 1/4" on the Gift of Good Measure design on Proofgrade, please contact us so we can investigate.

In my opinion the fact that you only offer support for proof grade materials is very short sighted. How many people actually exclusively use your PG Materials for all their projects?

I am a wood worker who bought this machine to exclusively engrave graphics on our pieces and make custom pictures (which work great it we float the image over the sides and don’t try to focus on exact alignments). Most of our custom made wooden projects are too thick to use the crumb tray without the head knocking it out of place so we have to use plywood to elevate it to 1.5-2" for the machine to work.

We are troubleshooting on our end and getting better results. Thanks

Andrew