Tip: Any downward pressure on the chuck will result in negative relief. To avoid this, keep your elbow lifted; this will keep you from applying downward pressure on the chuck.
- There a several things that can cause negative relief. The most common cause is not enough rotations made in the sharpening process. You should rotate the chuck clockwise from white line to white line until there is no more grinding. If you stop before the grinding noise stops this will result in negative relief. Over tightening, is the second most common cause of negative relief. If you tighten the chuck down too much, this will cause the metal fingers on the inside of the chuck to twist around the drill. Therefore, you should only tighten the chuck while the drill bit is in the alignment port and make sure not to over tighten. The third main causes of negative relief are due to worn parts. If you see flat spots worn into the sharpening tube (this is in the port where you actually sharpen the drill bit) this will result in negative relief.
- Keep in mind that the way the machine is designed to work; it will take the chisel off, put a new one on and finally start removing material from the rest of the surface. This means the very last spot material is removed from will be the heel. Negative relief is caused when the heel comes up higher then the cutting edge.
- Negative Relief will occur when you are not keeping the chuck cam riding against the cam guide when you are doing the rotations.
- Always keep the chuck in constant contact with the cam guides when you are doing the rotations.
- If you are not doing the correct amount of rotations this can also give you a Negative Relief angle on your bits. Try rotating until the
- If your bit is heavily damaged your will need to rotate the bit until you no longer hear contact to the wheel. Once this occurs, remove the chuck from the sharpening port, re-align the bit in the alignment port and start over. This time do the correct amount of rotations for the size bit you are sharpening. This should give you the results you need to get a correctly sharpened bit.
If you are still having issues please call 1-800-418-1439 for a customer support person to guide you through this matter.