Even if you only make occasional circuit boards, a miniature drill press is a great tool to use. With a 3D printer you can make your own for a few dollars.
I thought I would do a follow-up article on the 3D printed PCB drill press made in 2017. For years, I had used an Archimedes (press) drill for making holes in printed circuit boards. This works for low volume, but suffers from the tendency to break the tiny bits too often.
A drill press has the advantage of stability, ease of use and most important, making sure the tiny bit is exactly vertical to the surface. I found that poor alignment was the most frequent cause of breakage.
My miniature drill press is a modification of a Thingiverse design. The electric motor runs off 5-12 VDC and achieves up to 20,000 RPM. A solid mount is achieved with a couple of M2.5 screws. Since my creation of circuit boards is best described as “occasional”, this light duty tool fits the bill. It cost me around $15 to build, all in.
Whenever I need to use this miniature drill press, I just attach power from my bench supply with variable voltage to adjust speed.
All the parts needed for this project are readily available on eBay. You can also find a variety of bits, chucks and collets. Some experimentation is required to make sure the parts are balanced and minimize your drill’s run-out.
Miniature Drill Press – PCB Hole Sizing
In the above picture, you can see holes drilled for an RJ45 breakout board. Usually, I drill the holes before I clean off the resist.
My collection of bits ranges from 0.6 to 1.5 millimeters and these are fine for most pads on a PCB. Generally, I try to make the pads, and therefore the holes, as large as possible. Rather then just using your PCB CAD software defaults, you should select trace widths and pad dimensions to make life as easy as possible when fabricating the board.
Sometimes it makes sense to drill a tiny pilot hole as a guide, then use a wider bit for a second pass.
Lighting is very important. You need to see what you are doing in order to line things up before you press down on the drill.