To successfully engrave tumblers, what you need to have for your laser engraver is a rotary attachment. The rotary attachment holds the tumbler and allows it to rotate as it is being engraved. If you have a clamp on your rotary setup, I recommend using it for tumblers. The clamp holds the tumbler in place and makes sure it rotates properly. Incorrect rotation leads to a distorted engraving of the logos and wasted product, time, and money.