The Bottle Effect and how to engrave on bottles with a narrow neck

What is the bottle effect?

When using a laser engraver, one common issue you might encounter with a roller rotary is the “bottle effect.”

This occurs when you place a bottle with a narrow neck and wide body onto the rotary.

If you position the narrow neck on the roller wheels, the engraving on the wider body may come out stretched. This happens because the laser doesn’t account for the difference in the distance traveled by the narrow and wide parts.

How do you fix the bottle effect?

To fix this, simply turn the bottle around and place the wider body on the roller wheels. You can also use the Mega Clamp to help increase the friction if you need to do a full wrap and can’t have any slipping.

The setup pictured will eliminate the bottle effect and reduce any slipping to a minimum. Make sure to use the stoppers on your PiBurn!

What else can you do?

It’s important to note that the bottle effect only impacts roller rotaries. With chuck rotaries, the neck diameter isn’t a concern—only the diameter of the body matters, making them a better choice for objects with varying diameters.

If you are setting up the same bottle on the Grip or Grip 2, you only need to measure the diameter of the body, not the neck. There will be no bottle effect on the Grip or any other chuck rotary.

How about something crazy like this Jug?

Still, no bottle effect on the Grip2. Just measure the wide body diameter and you’re good to go.