Drill bit sharpening jigg

thingiverse

I print these in ABS, 0.3mm layers, carefully orienting them on their side to avoid unnecessary supports. To ensure proper placement, I align the side with the numbers facing towards the hotbed. Standard drill bits are designed for all-purpose use and typically feature a 118-degree point angle and a 12-degree lip angle. Hard metal drill bits, however, often have a more pronounced 135-degree point angle and a narrower 9-degree lip angle. To create split-point or self-centering drill bits, I start by grinding a 20-degree relief angle into the bit's surface, then carefully touch up the lip to achieve either a 12-degree or 9-degree angle. This process can be seen in action here: https://youtu.be/6iuLoo-qI2s. When drilling deep holes, I find that using a 55-degree relief angle significantly reduces the heat and force required to push the bit through the material.