Kerf explained

What saw kerf is, how it is charged at each cut, and how it changes a plan.

Kerf is the width of material the blade removes as it cuts. On a table saw with a 1/8″ blade, ten cuts turn 1 1/4″ of material into dust, and no part can use it.

How NestSmart charges kerf

Sheets and rolls: each cut removes a strip as wide as the kerf, and the parts on either side are placed around it.
Linear stock: kerf follows each cut along the stick. When the drop after the last piece is narrower than the blade, the blade simply runs off the end and no kerf is charged for material that is not there.

Kerf is reported apart from waste in the results, so you can see what it costs and what a thinner blade would save. With the plan open, press C to show cuts and kerf on the canvas.

Setting it

Set Kerf in the Optimization section as you would write it: 1/8, 0.125 or 3 mm. Through the API, kerf can also be set per material and per stock item; the most specific setting wins. A trim cut along a sheet’s edge is not charged kerf, because the trim allowance already covers it.