Off Center?

I put my design on a (cutting board), it looks perfect on my computer screen, then I engrave it and it isn’t printing where it was on the computer screen.

Warning: long explanation incoming.

There’s a camera on the lid of the machine pointing at the crumb tray. It takes a picture of your material, which shows up on the GF application, bordered by some rulers, and you line up artwork with your material that way.

But how does the Glowforge know how big or small to make the camera picture so the rulers are accurate and you’re lining up your artwork with a life-sized image? After all, a 9 inch cutting board will look larger than 9 inches if it’s closer to the camera, and smaller than 9 inches if it’s further away from the camera. That’s just how vision works, right?

It can only scale it to show up as 9 inches on your screen if it knows EXACTLY how far away that cutting board is from the camera.

Since the distance from the camera to the crumb tray is a known number, the only unknown is how thick your material is. If you use Proofgrade materials, the thickness is programmed in. It’s still an approximation, since every piece of wood or plastic varies a little from the next, but it should be pretty close. That means the camera picture will be scaled pretty close to “true to real size”.

But if you put anything else in the machine, like a cutting board, it won’t know, and the picture won’t be the right size. If you line up your artwork with that picture, it will print somewhere other than where it shows on your screen… unless you provide the material’s thickness.

And you can do that by measuring it, or asking the Glowforge to measure it. The “Set Focus” button tells the Glowforge to go measure the material height using its laser range finder on the bottom of the print head. If the measurement it comes up with is different from the height of the material you had selected, you’ll see everything “shift” on your screen as the camera image is scaled to true size.

If you place your artwork before doing this, it will print somewhere other than where you expected, because you were lining things up with a picture that didn’t reflect reality. If you use “set focus” BEFORE placing your artwork on any non-Proofgrade material or object, it will print where you expected.

TL;DR: Use the “set focus” button before lining up your artwork on a cutting board.

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Also, in addition to @dan84’s great reply, and in case you’re not aware, what you see on the screen is not the entire bed - it’s only the usable portion of the bed - so if you’re cutting board is larger than the usable area that part will be cut off.

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Oh no, I’m sorry to hear about the trouble @cricketthackett.

There are some excellent suggestions from @dan84 and @deirdrebeth.

Would you let us know if their guidance helped?

@deirdrebeth Your comment is the closest I’ve found to my issue, so I’m going to hop in here. I know the camera shows only the usable part of the material, but my camera doesn’t even show that. I’m using a piece of proofgrade medium maple and it doesn’t show the top 2 inches of my board and doesn’t pan or scroll to show me the rest of the board, I’ve done the calibration twice and it turns out fine and my cuts have all been exactly where I’ve placed them, but essentially this is wasting material. I know a design will fit on the material, as it’s not 12 inches in height, but the machine does not see or recognize the top part of the board. You can see in the image I’ve done some cuts but there is another inch and a half above those cuts of blank board. I’m loving my glowforge, but unless I fix this I’m going to be wasting material and that is not cool.

The vertical limit on the bed is under 11". (Actually about 10.95") If you need cut something out that is a full 12", rotate the design 90° so that it fits sideways on the board.

Horizontally you have a full 19.45" for cutting. Less for engraving unless you change the speed.

This has to do with limits on what the head can reach mechanically. There is an overlay on the screen (the rulers at the top and left side) that deliberately hide the parts of the board that the head can’t reach, to force you to place your design where the head can go.

So you need to work with what you can see when you are doing your placements. It’s doing what it is supposed to do, to keep you from wasting material.

If you want to use up the material underneath the overlay with a later cut, flip the board over and bring that area into the visible area at the front right, then cut it from the backside of the board. Both sides are finished and masked on Proofgrade material for that reason.

You will need to specify the material using the Unknown Materials button at the top of the left column, because it won’t be able to read the sticker if it’s still there. But it does let you get the most out of a full sheet, and it’s easy to do.

Start considering the lower right front corner as the origin with any new sheet, when you are doing your layouts…it saves a TON of material. And you can pull the sheet forward until it’s almost touching the door…make sure the metal grid part is completely covered.

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Welcome to the forum.
I suggest you download the file from this post. It will show you the 10.9" x 19.5" limitations of the Glowforge bed.

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THANK YOU @dklgood @Jules I thought I was losing my mind! Appreciate the explanation for the newb :slight_smile:

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