Determining When Blades Are Bad…or Not Worth Sharpening Again
by Jeff Andrews, Northern Tails Sharpening, Inc. www.northerntails.com
Do you know when a blade is worth re-sharpening? Or when it is too damaged to be re-sharpened? This article will help you make those decisions by discussing different parts of clipper blades, and what bad and good parts look like.
The Cutter Teeth
The cutter is the top blade of the blade set. It moves back and forth by the lever of the clipper. Whether the cutter fits larger blades (Fig. 1), or #40 blades (Fig. 2) , all teeth must be present on the cutter. Steel cutters with missing teeth, or ceramic cutters with broken tooth ends, cannot be fixed. These parts can be replaced making blades good again.
With ceramic cutters pay special attention to the tips of the teeth. If they are chipped or broken they may not work because when very blunt and simply just snag or drag. Ceramic cutters are basically glass. Ceramic blades should not be used on dirty dogs that are not combed out. Knots in the hair and dirt in the coat will chip the tooth ends and cause the blade to drag.
The Cutter Rail
Cutter rails are on the underside of blades, and generally hidden from regular view. They play important roles because they do the cutting. They also keep cutters raised enough to allow cut hair to move out of the way.
If rails are ground flat like the ones shown (Figs. 3 and 4), cutter blades are poor and won’t cut. Using blades with cutters without rails may cause them to drag or snag hair. Steel cutters are prone to being ground like this over time. Ceramic cutters are not prone in the same way because they are sharpened a different way. Cutters in poor condition cannot be fixed but can be replaced making blades useful again.
The Comb Blade
The comb, or bottom blade as it’s sometimes called, is the most important part of a blade. It determines the height of the cut. There are two styles, full and skip tooth. There is another style by one manufacturer called “Show.” The comb blade on this type has twice as many teeth as the “Full” type.
Figure 5 shows a perfect comb blade regardless of size. Notice it has no broken or missing teeth, and the front and rear rails are not ground flat. The front rail of the cutter and comb are the cutting surfaces of the blade. If any of the front rail is ground flat, it may cause the blade to snag or drag. You can inspect the rail of a blade by pushing the cutter to one side and taking a look, and then to the other side and taking a look at that side of the rail.
The comb cannot be fixed or repaired It must be replaced. You can take the blade apart and salvage the cutter, spring, socket, and screws for spare parts.
Broken Comb Teeth
Most groomers will use a #40 blade with one tooth missing (Fig. 6). It barely causes a line and may never cut skin. The blade on the right has several teeth in a row missing, this is a dangerous blade to use alone or under a guard comb. The comb cannot be fixed or repaired, so the blade will have to be replaced.
For blades larger than #40, most groomers use a blade with an outside tooth missing because 95 percent of the blade is still good and may not cut skin. In Figure 7 the blade has teeth missing in the middle. It will cause a line in the cut because two teeth are missing next to each other, and the blade may cut skin. The comb cannot be fixed or repaired, the blade must be replaced.
Missing Rail on Comb Blade
When the rail is ground flat as shown in Figures 8 and 9, the blade will drag or snag in the coat. The rail creates space between the bottom and top blades so there is space for hair to move out of the way of the cut, take this space away and it causes problems.
The blade in Figure 8 has only one side of the rail ground flat. The flat side will drag and the other will cut. The blade in Figure 9 has no rail left at all, this blade will not cut at all. The comb blade cannot be fixed or repaired, so the blade will have to be replaced.
NOTE: If a rail is very thin from previous sharpening, the next time you get your blade sharpened it could look like the above blades. A good sharpener will note this condition for you.
During the sharpening process, when the blade reaches the sharpening wheel, it’s best for the rear of the blade to touch first, similar to the heel of your foot touching the ground first when walking. This prevents the teeth of a blade from getting rounded if they were to touch first. You can see the ground area at the rear of the comb blade in Figure 10. It will not affect the way the blade cuts, it’s OK to have it re-sharpened.
Other Parts of Blades
The clipper blade has several other parts: the spring, screws, blade guide and socket. If any of these parts are broken or missing, and the cutter or comb has no broken teeth or missing rail, your blade can be re-sharpened. These small parts can also be replaced by sharpeners.
If you have determined your blade cannot be re-sharpened or repaired, take the blade apart and save these as spare parts. They will fit any blade. Every groomer should keep spare blade and clippers parts. It could be the difference between being to groom or not until you have your broken equipment serviced.
Check into a good blade care program and use oil as a lubricant and refrain from using spray coolant.