PCB Drilling Aid

[jpanhalt]

Here's an idea that popped up in the Homebrew PCB group to aid in drilling PCB's. It is not quite CNC, but not quite as hard to build either.

**broken link removed**

Re: Drill press

I also use this setup.I mounted a thin project box to the table with a laser
pointer, a mirror at 45 deg and a pinhole inside to illuminate the bottom of the
PCB. The pin hole is made by mounting a brass shim and drilling the hole with
the smallest bit that you have. A degree of fiddling is necessary to get the
laser beam directly centered on the pinhole. But once it is adjusted, the beam
is strong enough to illuminate the hole to be drilled from below. There is also
a bit of diffusion through the FR4, but the center of the spot of light is
exactly aligned with the bit. the top of the project box serves as the table
which is OK for small PCBs.

The drawback is that once it is calibrated you can't remove the rotary tool or
rotate the arm. This arrangement largely eliminates the depth perception
problem; where the spot of light is, is where the drill bit will penetrate the
PCB.

Baxter

John

 

[cr0sh]

Interesting solution - further down in the thread is mentioned the fact that the PCB has "holes" etched in the pads where the physical holes are to be placed, so that the laser will shine thru properly...

 

[jpanhalt]

In Eagle, there is a ULP called drill-aid that is very useful for setting etched holes in a PCB. Basically, it puts a user-definable hole in the center of each pad. If that hole is kept on the small side, it acts to center the drill. I can't imagine trying to hand drill a PCB without the holes marked as such.

John