开云体育

So you use a tv camera now for your
drilling? I have one of those cheap USB cameras that is a magnifier. Is
that what you used?

Actually, no. It's a bit more elaborate than that.

I have a linear rail that has about 6 inches of travel, then machined
a holder that holds the clamp for a proxxon drill. The 12 volt
version works just fine. That is driven by a linear stepper motor
(shaft attached, goes in and out of the motor).

That in turn is driven by an old, but standard design (L297/L298
stepper driver system). There are sensors on the linear rail for
bottom sensing and top sensing.

I found an old Pace desoldering stand, the kind used for a hot air
desolderer. It has a fixed height arm with a rack and pinion stage
for lowering the soldering tool.

Cut a hole in that base and mounted the proxxon upside down so it goes
through the center of the hole. Mounted an old vacuum cleaner nozzle
with a flexible extension so it removes debris from the underside.

On the top slide, I mounted a surveilance TV camera, this one runs on
12 volts too (most run on 24vac, and they're NOT kidding about the VAC
part because there's a small transformer in there that won't tolerate
DC). With an extender, it short focuses enough that I get
magnification. The small monitor is mounted above the camera.

The electronics allow you to home, and set maximum travel. Pressing a
footswitch starts a drill cycle, turns on the drill, moves it to the
up position, then back to a rest position.

You need to recalibrate the xy position each time you change the drill
bit, however.

With that, I can get very very close (say .001, I think) to the center
of a hole by using the crosshairs on the monitor. Some 3D printing
would help out the project, since the original design was to use the
vacuum to hold the board down once the drill bit moved up. That
didn't work as well.

So no, no USB camera. You could use one easily enough. The
electronics could be duplicated easily enough with an arduino, but I
used a board that was designed to run a small graphics display that I
had a few of....

So you get to see the position, and where it is in the cycle.

A bit of overkill, perhaps, but it has proven its worth in board
drilling. It does, by design, completely eliminate the parallax
problem which was a great inconvenience.

Harvey