Manually sharpening a drill bit is quite difficult. It is important to smooth it respecting the correct angle and it is practically impossible to do it freehand. To make sure you do accurate work, you need to use a special grinding wheel; if you don't have this tool, you have to build it yourself!
Steps
Part 1 of 2: Using a Sharpening Wheel
Step 1. Insert the drill bit into the drill holder
When you're ready to sharpen it, slide it into the wheel holder so that it protrudes slightly over the edge. Make sure it fits snugly into the slot - it should sit exactly in the center groove.
Bring the tip closer to the grinding wheel; However, avoid pushing it against it until you have started the machine
Step 2. Start sharpening it
When you are ready, start the engine and push the bit towards the grinding wheel; slide the media back and forth with one hand while holding the tip in contact with the abrasive surface with the other.
- You also need to twist it slightly as you sharpen it; slowly rotate it clockwise.
- It is important that the edges are as symmetrical as possible; using the sharpening wheel, the process is much simpler than with manual work.
Step 3. Use water to cool the tip if necessary
If you have to sharpen it a lot, you need to dip it in water about every minute to make sure it stays cold; continue to sand it until all edges are even.
Step 4. When finished, try it out
After sharpening it should be much more efficient than before; you can test it on a scrap piece of wood or a metal surface to make sure it is sharp.
Remember that if you are going to drill into metal, it is best to use a pillar drill; In fact, to penetrate into this material you need a lot of pressure even with very sharp tips and a manual drill may not be enough
Part 2 of 2: Building a Sharpening Wheel
Step 1. Get a piece of scrap wood
A small plywood plank is perfect for this project, but you can use any wood you have available that you no longer need; check that the board is about 30 cm long and 10 cm wide.
Step 2. Measure an angle of 59 ° and draw a segment to outline it
Typically, drill bits have an ideal angle of 118 °, but the holder must respect an angle of 59 ° to achieve this. Take the appropriate measurements and draw guidelines before cutting the piece of wood.
If your table saw has a protractor, set it to 59 ° and use the blade to make a notch in the wood
Step 3. Cut a slit along the line
Start the table saw and slide the piece of wood towards the blade, so that it goes through completely; you can use another piece of wood to drive the first one in a straight line under the saw.
- Create a "V" incision in the plywood; this represents the housing that holds the tip in place as you sharpen it.
- Wear safety glasses and keep your hands off the blade.
Step 4. Inspect the notch
After making it, check that it is big enough to hold the tip; if not, enlarge it slightly.
