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Using a Belt Sander to Sharpen Your Knives and Gouges Every experienced wood carver knows the value of having sharp tools. Often those new to the art of wood carving find sharpening their tools a challenge that with time, perseverance and patience is overcome. Larry, like many wood carvers, was in search of the perfect system for keeping his knives and gouges sharp. Finally, he decided to build a sharpener for his own use that would be "perfect" for his needs. Word spread and now many students in Larry's classes and other experienced carvers have purchased the Nowell Sharpening System. This page explains the Nowell system. You may E-mail Larry Nowell if you are interested in building such a system or if you want to purchase the sharpening system from him. The sharpener is $150 plus shipping and handling. Click here to send him an E-mail about the sharpening system.The Nowell Sharpening System
There is an adjustment knob (D) next to the backboard to adjust the belt tracking. The belt will rarely need realignment. |
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If the belt should move off center on the wheels and the metal backing, minor adjustments can be made with adjustment knob (D). When you see more metal on one side of the sanding belt than on the other, try tuning the adjustment knob and observe the direction the belt moves. Turn the knob the appropriate direction to adjust the belt to the center of the wheel. The belt sander comes with a set of belts from fine to course grit. Use the courser belts for grinding and shaping and the finer belts for freshening up a tool. Knife Sharpening
NOTE: To protect your tools from overheating you must frequently dip the knife blade in cold water. Take one light swipe of the knife blade against the belt and immediately dip the blade in water. Don’t look at the tool before dipping it in water because the heat continues to build up. Courser grits of sand paper on the belt will generate less heat. The sharp edge of the knife will always be facing toward the arrow
on the top of the belt sander. Hold the knife firmly while lightly
touching the belt at about a 30 degree angle from the heel to the tip of
the knife in relation to the belt. At a 30 degree angle only a
small portion of the blade touches the belt as you draw the knife from
the heel to the tip of the blade. This allows the tip of the knife to
come in contact with the belt for a very short time. The knife
blade immediately goes in the water to cool. The tip of the knife will
overheat very fast. Therefore, it is important that you minimize
the time it is against the belt sander. You can change the belts without losing your angle. Continue to change the belt going up in grit size until you get to 320 grit. Switch to a leather belt to further hone the tools. Changing Belts: Changing belts is easy. Remove the side cover (if you have one). Pull the belt off of the wheel by pushing it away from the motor on one of the three wheels. When putting a belt on, check to see if it has arrows on the inside. If there are arrows printed on the inside of the belt, put the belt on so that the direction of the arrows match the direction of the belt's rotation. Sharpening Gouges: When sharpening gouges the sharpening system sits in an upright position with the belt running vertical. The big arrow is facing the ceiling. Carving gouges work best when the bevel is flat, as opposed to rounded, and there is only one bevel. The Nowell Sharpening System will allow you to grind your gouges to this maximum performance shape.
To accommodate various sized gouges, parts A1, A2, B and C are used in the slide adjustment. These parts are used to position the gouge in front of the belt at the appropriate angle depending on the size of the gouge. A1 is used to shape full sized tools. A2 is used in conjunction with B to accommodate medium sized tools. A2 is used with B and C to shape small palm tools. The following three pictures illustrate the parts used for a full sized gouges, medium size gouges and small gouges.
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| Part A1 with full size tool. Parts A2/B used with medium size tool. Parts A2/C/B used with palm tool. | ||
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How to Use the Slide Adjustment and Parts (A1), (A2B), and (A2BC) To set the angle of the gouge, place your tool in the proper cup according to the size of your gouge. (See the guide on the top of the sharpener and the description in the prior paragraph.) Unscrew the side screw until the slide moves freely. If your tool is on the list posted on the guide on the top of the system, set the slide as shown there. Otherwise, guess at the angle by adjusting the slide (A1, A2) in or out until the bevel aligns with the sanding belt, and then tighten the side screw. With the grinder running, allow the tool to lightly touch the belt throughout its sweep. Look at the tool's bevel. If the scratches are on just the tip of the tool, push the slide in. If the scratches are on just the bottom of the bevel, pull the slide out. Once the scratches are in the middle of the bevel, continue to lightly move the gouge against the sanding belt throughout the sweep. Be gentle with the outside edges of the sweep, they will over heat quickly. When a tool is over heated it will lose its temper. Keep the tool cool by dipping it into water. Hold the tool with very light pressure sweeping it from one side to the other side against the belt (it takes about 2 seconds). Immediately dip it into the water. Repeat this process until a burr is formed. (A burr looks like fuzzy metal along the sharp edge of the gouge.) When there is a burr evenly throughout the sweep your tool you are ready to go to finer grit sanding belt or to a leather belt. |
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To
sharpen knives, place the sharpening system on a small table or the end
of a workbench which is accessible from both sides. Lay the unit
on its back with the arrow on the top of the belt sander pointing to
your left and the belt facing up toward the ceiling. The sharp
edge of the knife must be facing left and toward the arrow.
Carving knives work best when the blade is flat and has only one bevel.
It takes a soft touch to grind, shape or freshen up a knife blade.
Practice with less expensive knives until you get the feel for it.
Always keeping the sharp edge of the blade facing toward the arrow on
the top of the belt sander, walk to the other side of the sander and
repeat the steps with the other side of the knife. The sharp edge
of the knife is now facing right and toward the arrow.) Continue
alternating sides of the belt sander until both sides of the knife are
flat and you have a burr on each side. (A burr looks like fuzzy metal on
the sharp edge of the blade.) When you have the burr on both sides for
the full length of the knife, you need to change to a finer grit on the
belt to polish your knife.