Common dental drills are useful/required to have in any systems lab. In addition to the usual applications, these can be used to cut holes in cover slides (diamond abrasive burrs), to cut small openings in drive implant bodies, smooth out dental cement, or even metal parts, etc. However, dental drills are quite expensive when purchased from vendors of dental supplies. Luckily, the only key part of the system that seems to be hard to find cheaply, the air regulator and foot pedal, can be made with parts available from amazon etc. just by screwing together some air hose fittings.
In total, this bill of materials combines to a fully functional, brand new dental drill for a total of <$100 excluding the bits/burrs. This list can entirely be ordered from amazon, and can likely be had a bit cheaper on aliexpress or similar.
Hand piece, the actual ‘drill’ part:
Any 2-hole handpiece will do, here’s a nice option for ~$30 that has a built-in LED that is powered by the turbine. These are available in low-speed/high torque as well, and/or at various angles.
We can make the foot pedal/regulator from a simple foot pedal ($15 at amazon, 12mm threaded connectors) and a regulator ($9 with 1/4″ NPT thread). Now we just need some push-to-connect fittings for 6mm hard plastic tubing that work with the 12mm and 1/4″ NPT threads, so for instance these for $8 (they’ll need some teflon tape or epoxy to not leak on the 12mm threads), and some 6mm pneumatic tubing, like this for $10. To attach this to your air outlet, some other 6mm push-to-connect fitting with an appropriate threading might be needed.
Instead of the 6mm hard plastic tubing, just about any air hose could be used, but I like this option because the push to connect fittings are easy to use and the hose is easy to cut to length and is fairly thin and doesn’t get in the way. For the low pressure section of this, a more flexible tube like some thick wall tygon tube variant with barb connectors could likely work as well.
Now we just need a standard 2-hole style handpiece connector, (~$10 here or anywhere really) – conveniently, the common tube OD on these is ~4mm which fits snugly into the 6mm pneumatic tubing, and this part of the system is pretty low pressure, so a bit of glue and/r heat shrink tube is enough to connect the handpiece to the pedal/regulator combo. I also removed the water delivery tube from the handpiece connector, and cut off the thick protective tube that surrounded the air and water tubes, so only the air tube is left. This makes the drill a bit less robust, but removes almost any tugging from the hose and makes handling the drill easier. If the air hose is ever damaged it could be easily replaced by any type of tube that fits over the barb in the 2-hole connector.
Now these parts fit together in the obvious order: air outlet > regulator (watch the direction – there’s one input and one output) > foot pedal (also has one input and one output, plus a ‘bleed’ output on the side, ignore that one) > handpiece. The regulator could also go right next to the air outlet. Here, I screwed it to the foot pedal to make a neat little unit. I just drilled out a hole in the top of the pedal housing and used a M6 screw and nut for this.
For the burrs, we typically use Round, #1/4 carbide burrs for craniotomies and burr holes, and sometimes a #2-4 for thinning and/or to remove large amounts of cement. This is the only part of the system that can’t be ordered on amazon, but is quite cheap anyways.