Keeps Messing Up Glass Dish

Hey eveyone! So I am having MAJOR issues trying to engrave with my Glowforge. I have tried engraving a glass pie dish 4 different times now. The dish is only 1.6 inches so I was generous and said 1.8 which is DEFINITELY lower than the 2 inches it claims to be able to engrave. I’m not sure what I’m doing wrong but it always messes up in some way.

First one it somehow got off track and shifted the design halfway through
Second one engraved deeper in some parts than others
Third one did way better but burnt some parts (which came off with a TON of elbow grease) but was still missing some parts
Fourth one was the worst. It was doing good except not engraving completely in a few parts but then went COMPLETELY off track and started engraving the edge off to the side. I have attached a photo of this one.

I can add photos of the others if asked.

I have also cleaned EVERYTHING as well as done the official calibration we can do and still not quite lining up there either :confused:

When you remove the honeycomb tray for engraving thick items, you need to elevate the surface to be engraved so that it is within the 1/2" focus range of the Glowforge. Items that have a lip or rim around them are difficult to engrave because the printhead must not hit the rim, but the bottom area to engrave must still be within 1/2" of the lens. I cannot tell from your photos how deep your dish is, but all of your problems are related to proper focus.

There are many posts here in the forum explaining how to engrave without the honeycomb tray.

Here is one recent thread: Keeps changing my thickness and I get and error

The pie dish says it is 1.6 in and when measured it is actually 1.8 because of the lip. So I figured this was close enough to the 2in that it should still work :confused: it shouldn’t be too tall but I don’t understand why it works sometimes and not others and some parts are fully engraved while other parts are not

How tall is the lip - what is the distance from the edge of the lip to the area you want to engrave?

I turned the pie dish upside down so I’m engraving on the bottom so you see the design from the top and turned upside down the entire size from bottom to top where I’m engraving is 1.8 inches

OK, you should be able to do that. Are you using the set focus tool before placing your artwork?\

I use it after I put my item in there. I put the pie dish in, place my design, then click on the middle for the set focus. Sometimes I get a message saying the material is not registering right and sometimes I don’t. Sometimes I even get a message after I hit print saying it canceled my print. I’m honestly just so lost at what to do

Is the bottom of the dish flat? Your photo make it look like there is a rim. For alignment, you need to use the set focus tool first and make sure the beam lands squarely on an area where your design will be. After the camera adjusts from the set focus procedure, place your artwork.

You seem to be having two issues. Proper settings to achieve a good engrave on glass, and focus issues so the Glowforge knows where to focus the laser. The two are related in that you won’t get a good engrave unless the laser is properly focused. Sadly, you have several ruined dishes but on the bright side you have some material to test. I suggest you take one of the failures and work on getting a good result with a very small engrave.

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Thank you! I will try that. The dish is glass and therefore clear so I put painters tape on it. Would you suggest taking that off?

The tape will help provide contrast so that the set focus tool will work properly. As for engraving glass, I don’t have personal experience so I suggest you read through the posts here in the forum regarding best practices for that. I know this is a frustrating experience, but hang in there, read posts, run some test engraves and pretty soon you will be successful. Lots of people here to help.

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thank again :slight_smile:

The fact that it’s shifting mid-engrave strongly suggests that the laser head is bumping into something. If that’s not the cause, then could be debris on the rails, a loose belt, or some other mechanical issue. Either way, if that’s happening then even dialing in the perfect settings isn’t going to fix it. Personally, I’d try to solve that first and then come back to how to get a good quality engrave on glass.

If you have the patience, you can set the power really low so that it only marks the tape and that way see if it gets through a complete run without ruining any more of your dishes. It’s also a good way to test the alignment before you start. You could probably do a low-power score around the outside and make sure it’s placed properly before starting the real job.

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I have a question - first time owner and suce but what speed are you using to engrave??? I want to engrave on a piece of glass but I’m unsure of the speeds and such to do so

I see you already emailed us about this and we’re working on it there, so I’m going to close this topic.