I’m sorry that you’ve run into trouble when using Set Focus and setting up your recent prints. I extracted the logs from your most recent prints and Set Focus attempts to take a closer look, and it appears that the material you’re printing on might be close to or a bit over 0.5in thick. It also looks like the material might have a bumpy surface, which could impact the measurement that Set Focus takes.
You can print on objects up to 2" thick by removing the crumb tray. However, your Glowforge can’t focus too far down, so you may need to put something laser-compatible underneath your material to lift it up. Raise it until the top surface of your material is between 1.5" and 2" (50 mm) high, measured from the metal plate on the bottom.
Our community has developed some great Tips and Tricks, and this illustrated guide might be just what you need.
If you look through the above advice and are still having trouble, would you be able to provide us with some more information about the material you’re using, and a few photos of how you have it set up? We’ll be happy to take a closer look!