The reason i made such a relatively complicated and large drill is because
it is prepared for a optical projection mechanism that was never fitted.
That said, the space under the table is dead useful for storing boxes of
drills and stuff, and the crosspiece on top of the machine is also heavily
used to put stuff on, so there isn't actually any wasted space.
Make sure the hinge point is at the same height as the PCB. This means
right at the bottom plate if you don't want to use any block under the
PCB. I found it comfortable to use a block to raise the PCB about 5cm, it
makes it easier for me to position the PCB since i can grab the sides. If
you raise the PCB with a block, you must also put the hinge up at the same
height for tangential action.
Consider putting a compartment under your drill, depending on where you
place it and what seating you have there it might be good to get it up off
the table so the action comes closer to your eyes. Wear a face shield for
safety.
Make a hole in the top plate behind the drill to put a suction nozzle
through for your vacuum, and add spot illumination.
I would guesstimate the minimum arm length needed is 30cm, maybe 35.
Use plywood at least for the upper plate since you need to make a drill
holder. MDF is crap wood and only good if you only need to screw through
it and don't need any good edges.
ST
I'm not sure about springs, how they compare to a counterweight.
On Tue, 17 Jan 2006 22:49:42 +0100, alan00463 <alan00463@...> wrote:
> Thanks, Stefan, for your comments. I got my Proxxon drill and am
>
> getting ready to build the drill press.
>
>
> I am seriously considering the two-plate design, using two pieces of
>
> half-inch thick (12.5mm) wood or plywood with a wood spacer and a
>
> piano-hinge. I would probably make it about 25 cm (10in) wide.
>
> Not sure how long of a lever arm to use--what do you think? I
>
> suppose that I will just let the drill bit eat into the lower board
>
> when top plate is pressed down. I suppose that I will place springs
>
> between the two plates to hold the drill bit slightly elevated above
>
> the workpiece when the operator lets go. Then when the operator
>
> applies downward pressure, the drill bit will be exactly vertical when
>
> the drill bit contacts the upper surface of the workpiece.
>
>
> I think this design would be even better than the one you built,
>
> Stefan. It would be lighter and occupy less space. I might have to
>
> attach an L-shaped pieces of wood to the upper wood plate to make sure
>
> the drill bit is always held perpendicular to the upper wood plate.
>
> I guess the longer the lever arm the better, so long as it isn't too
>
> hard to store when not in use.
>
>
> Alan
>