The question of how to sharpen a hand saw comes up fairly often. Saws that have been heavily used, or improperly stored over long periods of time, can easily end up feeling much duller than they originally did. When this happens, it usually becomes fairly obvious within a few pulls or pushes of the blade across the cutting material.
With a dull hand saw, the blade won’t bite easily at the start of a cut, lines are difficult to keep neat or precise, and making progress through thicker materials can be laborious. By contrast, the best cutting hand saw will be well aligned and will always have sharp teeth.
Sharpening a hand saw isn’t necessarily difficult, but it is important to carry out the task properly and safely. Furthermore, some saws aren’t good candidates for sharpening in the first place. For instance, this is usually the case with hardpoint saws, whose teeth have been treated and aren’t designed for lifelong use.
For some cheaper hand saws, blades (or even entire tools) can be more economical to replace altogether, especially once you factor in the time and other materials needed to perform a proper repair. It’s also worth noting that poor sharpening technique can be just as damaging as neglecting the tool in the first place:
- With rip cut saws, if one or two teeth end up slightly shorter than the others (either through heavy use or imprecise sharpening), the chances are that it won’t completely ruin a hand saw’s action
- If one or two teeth end up longer than the rest, though, you’ll quickly start to notice uncomfortable dragging and juddering when you saw
- For crosscut saws, the 'set' of the teeth (their alternating angles towards and away from the midline of the blade) may also need adjusting over time. If the set of the teeth is too narrow, the blade may bind when cutting. However, if the set of the teeth is too wide, it may feel loose in the kerf and show a tendency to wander
With all that said, once you’ve bought a good hand saw, it may very well prove to be something you want to keep in your tool kit for a long time to come. In that case, at some point, you will need to sharpen the teeth. Good saw sharpening technique can help you achieve great results with hand saws over many years of intensive use.
There's both a simple and a more complex approach to sharpening hand saw teeth. The more complex method (particularly for crosscut saws, as noted above) might involve any of several additional tools, such as a saw tooth setter. Here is a handy outline of the more basic sharpening technique for rip cut saws.
Tools You Will Need:
- A vice to hold the saw blade
- Vice blocks or wood to protect the tool
- A mill file (flat) and a taper saw file (triangular)
Both of these files are commonly found in good file sets. Any size triangular file that fits well between the saw teeth will be suitable.
- First, set the blade as low down in the vice as you can, while leaving the teeth themselves exposed as this will minimise wobble and flex as you file
- Next, use the flat mill file to level out the teeth. Hold it level across the tops of the teeth, perpendicular to the blade. Use light, even pressure in a side-to-side action along the full length of the blade, creating a small flat top on each tooth. You will be able to see these new flattened tops as bright, shiny areas when held to the light
- Once you have done this, you will need to switch over to the taper saw file. Place the file in the gap between two teeth, angled slightly towards the tip of the saw so it rests against the spine of the tooth being sharpened. Again, make sure to hold it level and perpendicular with the blade. Make two to three light sideways passes in the same direction for every tooth along the full length of the blade, maintaining a consistent action and number of strokes each time
- Once the shiny, flattened top of every tooth has been reduced to a pinpoint, all at a consistent size, the saw has been successfully sharpened. Make sure to test our your newly sharpened hand saw and if necessary, go back and make adjustments in small increments until the issue is resolved