How to Use the Planer Speed Chart The number of knives in the head is shown across the top. The feed speed through the machine is shown in the vertical column on the left. The body of the chart shows the finish, in knife marks per inch for a given number of knives and a given feed speed. Example: Let’s say your existing heads have a 12 3/16” cutting circle and are fitted with 16 knives. A particular material is run at 700 linear feet per minute (fpm), and you are satisfied with the finish obtained with this combination. Then reading across from 700 fpm and down from 16 knives shows a finish of 6.6 knife marks per inch (kmpi). 6.6 kmpi would become the basis for determining your new feed speed. You may then contact DESIGNTEK to determine the maximum number of knives available with the DT Gibs head. In this case, up to 28 knives are available for this head. Returning to this chart, start with 28 knives at the top, drop down the column under this number until you reach a figure as close as possible to 6.6 kmpi—in this case 6.7 kmpi. Then reading across to the left would give your new target feed speed—1200 fpm. return to chart |