12.4Whetting Knives (Straight Cutterhead)
When knives become dull enough so that it is noticeable when cutting, they should be resharpened or replaced. A sharp knife will work easier and last longer. The penalty paid for a dull knife is less blade life and greater wear and tear on all parts of the machine.
Jointer knives are very sharp. Use care and proceed slowly when working with or around the cutterhead.
Figure 34
1.Disconnect machine from power source.
2.Remove the pulley cover so you can rotate the cutterhead by means of the belts.
3.Use a fine carborundum stone. Cover it partly with paper, as shown in Figure 34, to avoid marking the table.
4.Lay the stone on the infeed table. Adjust the infeed table and turn the cutterhead until the stone lies flat on the bevel of the knife and flat on the infeed table.
5.Hold the cutterhead from turning, and whet the beveled edge of the knife, stroking lengthwise by sliding the stone back and forth across the table. Do the same amount of whetting on each of the three knives.
6.When finished, reset the knives parallel to the outfeed table. See “Setting Knives (Straight Cutterhead)”.
If knives cannot be properly retouched as described above, they must be ground and re- surfaced to a new bevel edge. Check in the phone directory under “Sharpening Service” or “Tool Grinding or Sharpening.” It may be less expensive to purchase a new set of knives. If the jointer is used often, keeping a spare set of knives on hand is recommended.
Knives (stock no. 6292535) may be ordered from your authorized Powermatic distributor or by calling
Gum and Pitch which collect on the knives cause excessive friction as the work continues, resulting in overheating of the knives, less efficient cutting, and consequent loss of blade life. Use "Gum and Pitch Remover" or oven cleaner, to carefully wipe off the knives.
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