Stock is never where the app thinks it is

[davidsi]

I’ve now printed four times with my GF, and each time, the app has not shown the stock to be where it actually is. When I line up the image to cut on the app, the place it actually cuts is off. This is with both prograde medium acrylic and non-prograde foam board.

The first two I did with foam board, and placed the image at the top of the stock and it seems a few inches away, the last two were at the bottom and were perhaps 1/4 inch off.

Any help would be appreciated.

thx

[Jules]

At the current time, the camera view of the image on the bed can be off by up to 1/4" at the edges of the bed. There is a fisheye effect with the camera that has to be compensated for by an algorithm.

So what this means to you, is that if you are trying to cut out accurately around something that has been drawn by hand or printed with ink, it’s going to be harder to do it accurately if you place the item to be cut out at the far edges of the bed.

You will get the least distortion of the image right underneath the lid camera, so try placing the artwork and items there.

Another thing that you have to be aware of regarding that algorithm, is that it relies on a very accurate measurement of the height (thickness) of the material being cut. If you are using the Proofgrade materials, that information is included in the QR codes supplied on the material. But if you are using something other than Proofgrade, you will have to accurately measure the thickness of the material with a digital calipers, and enter that thickness value (in inches) into the Unknown Materials button at the top of the left column in the opened file in the interface. (You will also need to specify your settings manually for non-Proofgrade materials.)

Doing those things will enable you to get much closer placement of your design on the item that you are engraving.

If you want complete accuracy though, I highly recommend use of a jig. It allows for perfect placement.

[davidsi]

Hi, thanks for the info. However, I have not drawn anything on the bed but imported images via the web.

[Jules]

In that case, you’ve got it even easier. Couple of tutorials you probably ought to read…they explain how to use vector drawing programs to create perfect alignment for your cuts and engraves.
(These demo in Illustrator, but you can also use Inkscape or CorelDraw if you are more familiar with those.)

Doing the aligning before saving the file is the way to go. It’s so much more accurate.

Glowforge Interface - How to Align a Double Sided Engrave

I’m going to demo an alignment process below using my (ancient) version of Adobe Illustrator, but the process is the same for Inkscape or CorelDraw or Affinity Designer. Whichever one you like to use, you’ll do the same things, with the tools in that program. (I’m also going to give you the thought process that goes into creating a design with 2D Design software, to keep from having to write another one up, so if you can slog through it, you’ll pick up some stuff you need to know to make thing…

This one is handy too:

Glowforge Interface - Vector Files Made Easy

It’s soooooo easy to create files easily in programs like Illustrator, Inkscape, CorelDraw and Affinity Designer if you understand what the Glowforge interface sees when it looks at your file. (Think of this as a last batch of Tips and Tricks, then I’ll quit bugging you.) I’m going to demo in Illustrator again, but the same things will be done in whatever program you choose to use for your designs. If you have questions about specifics for other kinds of drawing and modeling software, …

And there are several in the Tips and Tricks section of the forum that can really speed up the process if you have time to take a look - check the first post by Dan in the category, it’s the door to the Matrix.

[davidsi]

sigh. reading :-(.

thanks

[davidsi]

I’m not sure if it’s relevant, but the QR code for the proof grade stock is NEVER sharp in the image on the web app.

[rpegg]

That’s normal. Never seen one that looks in focus.

[pip]

I’m so sorry your prints aren’t coming out as expected.

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", we’d like to have you try a few troubleshooting steps for us:

1. Turn off your Glowforge.

2. Check for small pieces of debris or dust.

   • Check the lower door to make sure it closes all the way. It may require some force to open, but open it, wipe any dust off the edges, and close it all the way.

   • Remove the tray and clean any dust or debris from the surface underneath. Pay careful attention to remove all debris from the four dimples where the tray rests.

   • Check the lid to make sure it closes all the way. Small particles of material, such as dust or debris, can prevent it from closing completely.

3. Check the surface your Glowforge is on to make sure it’s flat. Ensure it is not twisted slightly and that there is no debris propping up one side of the machine.

4. Turn your Glowforge back on.

5. We included an extra piece of Proofgrade Draftboard with your materials shipment for troubleshooting. Place the Proofgrade Draftboard in the center of the bed and print the Gift of Good Measure using the default settings.

6. When the print finishes, leave the lid closed and wait until the fans stop and the picture updates. Without moving your artwork or your material, take a screenshot of the Workspace to show us the difference between the artwork placement and the actual print placement. Make sure to include the rulers in your screenshot and show as much of the bed as possible.

   • Mac: Press Shift-Command-4 and click and drag a box around your image. You’ll find the screenshot file saved on your desktop.
   • Windows: Click on the Start Menu and type “snipping tool”. Open the Snipping Tool > New then click and drag a box around your image. Click the Save icon and name and save your file.

7. Send us the screenshot along with the date and time of the print, and we’ll investigate.

Regarding the sharpness of the bed images, I extracted the logs to investigate, and it looks like the Proofgrade QR codes are being correctly detected in each instance I looked at. If you have trouble detecting Proofgrade, please let us know the time and date and we’d be happy to look into it for you.

[vee]

It’s been a little while since I’ve seen any replies on this thread so I’m going to close it. If you still need help with this please either start a new thread or email support@glowforge.com.