I still consider myself a newbie (owner since late Feb / Early March) with the Glowforge although I have been experimenting and feel fairly confident on it but I could still use some advice.
Someone has asked me to do some engravings on 12x20 3/4" board (Oak or Maple). I will also get a scrap pice to piece to experiment on. They would like a logo in each corner and text in the top middle. I know there are always edge areas I cannot engrave because it is grayed out… almost like a margin. I would of course automatically leave space on edges … but I do not want too much space, so… here are my questions:
Should I tell him the piece needs to be smaller like 10x 18 or even 11 x 19 to be safe?
Do I need to remove the crumb tray for a .75" board?
Yes, the honeycomb tray must be removed. Your best bet on sizing would be to get the artwork and see what a practical size would be. You can probably accomplish what the customer wants with a 12 x 20 board, but for the sake of efficiency, a smaller one would probably be better.
one thing to remember, you have more space vertically (i.e., the 12" side) inside the machine. so you can use a, say, 15x20 board and push the part you aren’t engraving further toward the back. then you can rotate it and do the engraving on the other corners (just upside down). i’ve done this with guitar bodies that don’t really fit w/in the 12x20 rectangle.
If you position a 20x12 sheet on the bed against the lower edge, the un-printable area is .7" across the top and left side, ~.3" across the bottom, and ~.25" along the right.
So your printable area is ~19x11. That means you would need to leave ~.5 border,
The bed itself has ~.9" along each side, so that gives you a ton of room to position a 20x12 piece so that it is centered on the printable area - just don’t center it in the machine, as that area is not where a print will be centered. You need to test to find the perfect location.
Before engraving on the actual piece, I think I’d do a prototype on cardboard. Just to make sure the engravings appear where you are expecting. You can use a very low power and low LPI just to get an idea.