Replacing Knives (Straight
Cutterhead Only)
Jointer knives are extremely sharp. Use caution and proceed slowly when working with or around the cutterhead.
1.Disconnect jointer from power source.
2.Remove the belt guard so that you can rotate the cutterhead by turning the motor pulley or by moving the drive belt. Do not grab the cutterhead itself to rotate it.
3.Remove the old knives by loosening the square head gib screws with an 8mm wrench. See Figure 36. The springs in the cutterhead will raise the knife for easy removal. Remove knife and gib.
4.Clean the gib and the knife slot. Sandwich the new knife and gib together and drop into slot. Make sure the knife is oriented properly in the cutterhead, as shown in Figure 36.
IMPORTANT: To position the knives for rabbet cuts, take a shop scale with 1/32” graduations and place it against the end of the cutterhead. Slide the knife out until it is at the 1/32” mark on the scale; that is, the knife will now be 1/32” beyond the edge of the cutterhead. The gib should remain in normal position, even with the edge of the cutterhead. See Figure 37. This adjustment will ensure that the knife clears the end of the gib and cutterhead, and has good contact with the workpiece. (See the “Operation” section for further information on rabbeting procedures.)
(NOTE: This same procedure can be used if a small nick develops in the knives; simply stagger the knives in the cutterhead to remove the effect of the nick, without having to replace the knives.)
5.The height and parallelism of the knife in the slot, both for rabbeting and normal jointer work, must now be set properly, to ensure correct operation as well as minimize the hazard of kickback. Refer to “Setting Knives at Correct Height and Parallel to Outfeed Table” on pages
Before starting the jointer, make sure all gib screws are firmly tightened. A loose knife thrown from the cutterhead can cause severe or fatal injury.
Figure 36 (straight cutterhead)
Figure 37 (straight cutterhead)
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