A tiny custom table saw

saw

If you’re working with small parts, even the smallest table saw available at Home Depot or Lowes is generally overkill. For cutting up small pieces of wood, metal, and copper-clad board, a micro table saw is a great investment. They’re actually pretty inexpensive, but why just buy one when you can make one that is better than any model on the market?

The bed is constructed out of 1/4″ aluminum plate with a 1/15 horsepower motor bolted to the underside. The fence clamps on to the table with a pair of delrin brackets, while the angle guide is made of delrin and a brass bar that fits into a slot in the table.

The actual blades came from a Proxxon micro table saw (a very good brand from our experience), but comparing this homemade saw to the commercial one provides a few surprises: The Proxxon has a more powerful motor, but the homebrew version has four times the cutting capacity. You can check out this saw cutting a 1/4″ aluminum bar in the video after the break.

Thanks [Hubert] for sending this one in.

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A portable CNC mill

Proxxon

Second only to a lathe, a mill is one of the most useful tools to have in a shop. For [juppiter], though, a proper multi-ton mill would take up too much space and be a considerable investment. His solution to his space problem is actually very clever: he converted a small, inexpensive benchtop mill to CNC control, and put everything in a nice box that can be tucked away easily (Italian, here’s the translation).

The mill [juppiter] chose for the conversion was a Proxxon MF70, a very small mill made for jewelers and modelers. After buying a CNC conversion kit that included a few NEMA 17 motors, bearings, and mounting plates, [juppiter] set to work on driving these motors and controlling them with a computer. For the stepper drivers, a few industrial motor drivers were sourced on eBay, driven by an i3 miniITX computer built into the mill’s box. Control is through a touchscreen LCD and a Bluetooth keyboard and mouse.

So far, [juppiter] has crafted a very elegant wood and brass CNC controller that allows him to jog the axes around and set the home position. It’s an excellent build that really shows off the power and ability of these inexpensive desktop mills.

Turning a rotary tool into a PCB drill press

Drilling holes in PCBs is nearly always an exercise in compromise; the holes are small, precision is paramount, and the common solutions, such as a Dremel drill press, aren’t of the highest quality. In a quest to find the best way to drill holes in PCBs, [reboots] even went so far as to get a pneumatic dental drill, but nothing short of a high-quality micro drill press would do. Not wanting to spend hundreds of dollars to drill a few holes, [reboots] did the sensible thing and made one from scratch.

[reboots] ended up buying a Proxxon Micromot 50 after reading the consistently good reviews around the Internet. To use this rotary tool as a drill press required more work, though. Two precision steel rods from a dot matrix printer were salvaged and pieces of aluminum C-channel and small bearings were bolted together into a very high-precision drill press. Only hand tools were used to build this drill press, and the results are amazing.

[reboots] was originally inspired to check out Proxxon tools from one of Hack a Day’s rare tool reviews. The Proxxon TBM115/220 earned the skull ‘n wrenches seal of approval (and found its way into other Hack a Day-ers labs), but sometimes a few hundred dollars is too much of an investment for something only used occasionally. Considering [reboots]‘ scrap aluminum drill press is a better tool than the sloppy consumer rotary tool presses, we’ll call this a success.

Tools: Proxxon drill press TBM115/TBM220

tbm220ii

A decent drill press is a crucial tool for an electronics lab. We use our drill press to make holes in our own circuit boards, and tap or break traces on existing circuit boards. We’ve used a lot of tools to drill circuit boards — power drills, power drills in “drill press stands”, and high-speed rotary tools — but when we started doing projects on a schedule, it was time for something more reliable.

We first spotted the Proxxon TBM115/TBM220 drill press in the window of a local shop.  Its tiny size and adjustable speed seemed ideal for drilling circuit boards. At $200, this is one of the pricier tools in our lab, but quality bearings and smooth drilling action aren’t cheap.  Read about our experience with this tool below the break.

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