A mechanism made of brass and steel is attached to a milling machine. It has a long lever extending from the right side, a counterweight attached to the left side, and an indicator gauge in the middle.

A Precision Drill Press For Tiny Bits

May 16, 2026 by Aaron Beckendorf 11 Comments

Anyone who’s worked with even a 1 mm bit knows that while a drill press is all but essential, it isn’t proof against broken bits. Working with a 0.1 mm drill bit seems, therefore, all but impossible, which is why [Mike] of Chronova Engineering built this mechanism to simplify such drilling.

The mechanism is an attachment for a milling machine, and in principle it just needs to move the rotating drill bit up and down. It needs to be extremely precise, though. For context, a good-quality chuck normally has a runout of 30 to 50 microns, which is approaching half the diameter of the drill bit. The mechanism has a collet mounted in the milling machine’s spindle, which transfers rotation to a second spindle. The second spindle is mounted to a runout-compensating drill chuck, and is connected to a lever and counterweight which allow the user to make small, low-force movements. A dial indicator lets the user see how far the bit’s descended.

Most of the parts were machined out of steel or brass, with the handle being made of titanium for lower weight. When the finished device was mounted to the milling machine, the measured runout was severe. After much investigation and reworking, however, the problem turned out to be a damaged collet locating pin, not an issue with the drilling mechanism. As a first test, [Mike] drilled a 0.1 mm hole 1.8 mm deep, then as a challenge drilled six 0.1 mm holes in the end of a thin steel wire. The results weren’t quite as uniform as he wanted, but it took a scanning electron microscope to even see the imperfection.

It won’t help much with very fine drill bits, but if you need a very precisely-placed hole, check out this periscopic drilling camera. If you do break a drill bit in the workpiece, you might be able to dissolve it with alum.

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Negative Reinforcement: Drill Bits Edition

March 20, 2021 by Kristina Panos 21 Comments

In theory, it’s fun to have a lot of ~~toys~~ tools around, but the sad reality is that it’s only as fun as the organization level applied. Take it from someone who finds organization itself thrilling: it really doesn’t matter how many bits and bobs you have, as long as there’s a place for everything and you put away your toys at the end of the day.

[Cranktown City] is always leaving drill bits lying around instead of putting them back in their bit set boxes. Since he responds well to yelling, he decided to build an intelligent drill bit storage system that berates him if he takes one out and doesn’t put it back within ten minutes.

But [Cranktown City] did much more than that. The system is housed in a really nice DIY stand that supports his new milling and drilling machine and has space to hold a certain type of ubiquitous red tool box beneath the drill bits drawer.

All the bits now sit in a 3D-printed index that fits the width of the drawer. [Cranktown City] tried to use daisy-chained pairs of screws as contacts behind each bit that could tell whether the bit was home or not, but too much resistance interfered with the signal. He ended up using a tiny limit switch behind each bit instead. If any bit is removed, the input signal from the index goes low, and this triggers the Arduino Nano to do two things: it lights up a strip of red LEDs behind the beautiful cut out letters on the drawer’s lip, and it starts counting upward. Every ten minutes that one or more bits are missing, the drawer complains and issues ad hominem attacks. Check out the demo and build video after the break, but not until you put your tools away. (Have you learned nothing?)

Okay, so how do you deal with thousands of jumbled drill bits? Calipers and a Python script oughta do it.

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Sorting Thousands Of Drill Bits

November 17, 2020 by Mike Szczys 42 Comments

[Austin Adee] came into some drill bits. A lot of them actually. But when thousands of assorted sizes are delivered in one disorganized box, are they actually useful? Not unless you’re drilling holes where diameter doesn’t matter.

So two projects were at hand: finding a place to store a few hundred different sizes of bits, and tackling the actual sorting itself. In the end, he used input from a digital caliper alongside a Python script that showed him where to put them.

The start of the tray design process was a bit of a research project, establishing the common sizes and how many would fit into a given space. This data was used to spin up the layout for trays with 244 different pockets to hold the bits. The pockets were CNC milled, but getting labels for each to work with the laser engraver was a bit of a hack. In the end, filling in the letters with white crayon really makes them pop, despite [Austin’s] dissatisfaction with the level of contrast.

But wait, we promised you an epic sorting hack! Unfortunately there’s no hopper, vibration feed, and sorting gantry that did this for him (now if it were perler beads he’d have been all set). Still, the solution was still quite a clever one.

A set of digital calipers with a Bluetooth connection sends the dimension back to a python script every time you press the capture button. That script find the pocket for the nearest size and then highlights it on a map of the drill bit drawer displayed on the computer monitor. In the end the trays fit into a wide tool chest drawer, and are likely to keep things organized through exactly one project before everything is once again in disarray.

[Austin] mentions a lag of up to one second for the Bluetooth calipers to do their thing. For assembly-line style work, that adds up. We remember seeing a really snappy reaction time on these digital calipers hacked for wireless entry.

Drill Bit Gauge Is Interdenominational Black Magic

March 26, 2018 by Zoe Skyforest 62 Comments

Oh, sure – when you buy a new set of drill bits from the store, they come in a handy holder that demarcates all the different sizes neatly. But after a few years when they’ve ended up scattered in the bottom of your toolbox for a while, it becomes useful to have some sort of gauge to measure them. [Caspar] has the solution, and all you need is an old steel rule.

The trick is to get a ruler with gradations for inches and tenths of inches. After cutting the ruler off just after the 6″ point, the two halves are glued together with some steel offcuts and epoxy. By assembling the two halves in a V shape with a 1 mm drill bit at the 1″ position, and a 5 mm drill bit at the 5″ marker, a linear slope is created that can be used to measure any drill bits and rod of the appropriate size inserted between the two.

It’s a handy tool to have around the shop when you’ve amassed a collection of bits over the years, and need to drill your holes accurately. Additionally, it’s more versatile than the usual method of inserting bits in appropriately sized holes, and can be more accurate.

Now that you’ve organised your drill bits, perhaps you’d like to sharpen them?