DIY PCB Drill Press
I have been using 0.8mm tungsten carbide drill bits for quite a while. I use it with a rotary tool free-handed, no drill press. I read all around the internet that these bits are really brittle and should not be used without a press. Well, I have never broken a single bit.
Lately, I’ve been wanting to get some smaller bits. I have about 10 pieces of 0.8mm bits from Ebay. Since I had such success with these bits, having 10 of them was rather redundant and wasteful. So, I thought I should get assorted sizes this time around, which means only 1 piece of each size. At these smaller sizes, I’m not really that confident with my hands.
Thinking about it, I noticed I had a pair of ball bearing drawer slides lying around. Aha, with some MDF scraps, a couple of hose clamps, and some screws, I could whip up a homemade drill press.
Unfortunately, I didn’t take any photos while I was making this. It would be very unproductive to stop sawing and drilling just to take a snap shot. Not to mention I didn’t want to get MDF dust on my camera (not that my camera is new or really expensive, I’m just a bit of a clean-a-holic). This whole project took less than 7 or 8 hours to complete.
The pictures pretty much sums up the MDF structure. A pair of drawer slides were sandwich between two pieces of MDFs. A screw is on each piece of the MDFs. The screws are on the inner sides of the sandwich and are offset from one another so as to not interfere or collide. I initially looped a rubber band around these screws but later replaced it with a proper spring.
Slots were cut on the front piece to accommodate the hose clamps and the clamps errr….clamped the rotary tool in place. The whole thing is supported with another two vertical pieces of MDFs on a base. You may have noticed that I cut off a good chunk from the vertical supports near the base. Most of the PCBs I make are pretty small-sized, but just in case, the cutouts allow me to drill holes that are far from the sides (or deep in the middle) of the work piece just by supporting it up higher.
I also added a lever to actuate the drill downwards. I used a screw on the vertical support as a pivot point or fulcrum for a length of aluminum. Another screw is located on the side of the front piece and the aluminum lever simply rests on this screw. Pulling the lever down will move the rotary tool down. One thing to note is that my lever was unnecessarily too long.
There you have it. Overall, a simple and rather inexpensive build. The slides cost about $15. The MDF scraps probably costs less than $10. The spring, aluminum, clamps, and screws probably total less than $20. So the whole thing costs less than $50 and I’m over-quoting most of the materials. It works really well too. The important thing here is to make sure all the MDF support pieces are perpendicular. If you do this right, the slides will handle the rest. It’s really smooth and there’s no play in the movement. I might add a depth stop later on. Still thinking about how I can implement it elegantly.