Tolerances in laser cutting

How much material does a laser beam remove?

Laser cutting is an extremely precise technique. For most materials, the laser beam removes only about 0.2mm of material. The exact amount is specified on each material page and may vary slightly. For materials thicker than 5mm, the cut width can be a few hundredths of a millimeter larger, and if this is the case, it is mentioned.

The cut is a few hundredths of a millimeter wider at the top of the material than at the bottom. This is almost unnoticeable with thin materials but becomes slightly more apparent with thicker (5mm+) materials.

What are the material tolerances?

Most materials also have their own thickness tolerance, which should be considered for joints that involve the thickness of the sheet, such as a tenon and mortise joint. 

Do I need to account for kerf or thickness tolerance in my design?

In the vast majority of projects, the kerf is negligible and you don't need to account for it. However, it is sometimes necessary, for example, with finger joints. In that case, you should compensate each part by half of the kerf. Be mindful that the width of the hole is still sufficient for the thickness of the material (plus kerf).