Sickle Scaler

There are two cutting edges to a sickle scaler formed where the lateral surfaces meet the facial surface. These two cutting edges meet at the pointed tip. There are two types of sickle scalers. One is straight, which results in a triangular cross section. The other is curved, which results in a cone-shaped cross section. This integrity of form must be maintained during sharpening.

These cutting edges are sharpened by activating a flat stone against the lateral surface of the blade, starting at the heel of the blade, progressing through the middle third and finally to the facial third of the blade using a light fluid up and down motion. After testing for sharpness produces an acceptable result as determined against the test strip, the instrument is ready for finishing to maintain the structural integrity of the facial surface; the facial surface is not sharpened vigorously, only honed to remove any metal fragments.

In the case of the curved sickle scaler, holding the instrument handle perpendicular to the work surface with the tip toward the operator, place the conical stone horizontally on the instrument face and gently rotate the stone from heel-to-middle-to-tip. Use a similar grasp for the straight sickle scaler; perpendicular to the work surface with the tip toward the operator, use the flat stone on the instrument face and gently moving the stone horizontally across the face (Figures 6a‑6c). The intent is to remove debris and wire edges, not to sharpen the face.

Figure 6a. Holding the Scaler.
Illustration of proper way to hold the scaler
Holding the instrument in the non-dominant hand, perpendicular to the bench top, at eye level with elbows on the bench, position the blade to be sharpened at the bottom such that the tip is easily visualized. This bottom tip should line up with the wrist, while the top shank is braced between the index finger and thumb.
Figure 6b. Holding the Stone.
Animation showing correction motion for sharpening a scaler
With the lubricated surface of the stone against the lateral blade surface, tilt the top of the stone to a 30 degree angle.
Figure 6c. Sharpening Motion.
Animation showing correction motion for sharpening a scaler
In a consistent up and down motion, starting with the heal and moving through the middle and tip third, grind the stone over the surface. Metal filings and or sludge will become visible on the blade surface and stone. These can be removed with gauze.

After sharpness testing produces an acceptable result, the instrument is ready for finishing (Figure 7).

Figure 7. Finishing Sickle Scaler.
Animation showing technique for  finishing a scaler
Place a conical or cylindrical stone on the facial surface and lightly spin along face to remove sludge.
Table 2. Sickle Scaler Step-by-Step Summary.
  1. Sit with elbows on a work surface. Position instrument perpendicular to the work surface.
  2. Firmly grasp instrument with non-dominant hand using index finger and thumb.
  3. Compare blade and shank of instrument to be sharpened to a new instrument, decide whether it can endure sharpening and still maintain original design, integrity and strength. Will the terminal shank be so thin that it may snap off during use? Decide to keep or replace instrument.
  4. Point blade tip away from operator to sharpen right cutting edge (point blade tip toward operator to sharpen left cutting edge.)
  5. Place sharpening stone against lateral surface so the top of the stone is angled 30 degrees away from the blade.
  6. Glide stone up and down in a smooth motion beginning with the heel third, progressing to the middle and anterior third of the blade.
  7. Wipe away metal filings and sludge.
  8. Do not activate the instrument tip against the stone.
  9. Test sharpness against test strip for “gripping” and sound.
  10. Finish with finishing stone.