Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hello all..I think I have yet another new PCB making "twist"!

Many may not know this but I was the FIRST to suggest the idea for
using glossy magazine "stock" for the direct toner method. I did
extensive searching on this group and the rest of the net prior to
making the post a couple of years ago to confirm no one else had
suggested it before (No point in suggesting "old news" ).

Here's an idea for a "twist" (Pun intended) on a different method.

The scratch and etch idea has been tossed around, experimented, and
succcesfully tried by others. All have relied on dragging a sharp
point across a "Blued" or coated circuit board.
The biggest problem was finding a suitable "Resist" that scratched
CLEANLY yet still gave protection from the etchant.

Another idea was the possibility of modifying a plotter somehow to
become a PCB etching machine. I don't think anyone succeeded in this
method because plotters are not strong enough to carry the drill head
or Dremel Flexi-Shaft (not to mention all the other problems).

How about combining the two methods !!!

Pager vibrating motors are VERY small...VERY light... and require
VERY little power to drive them. How about removing the offset
weight, sharpening the shaft to a point, and using the power that
drives the up/down solonoid of the plotter (thru a resistor since
little power is needed) to drive the motor. It'll fit EASILY into the
pen holder (in fact it's probably TOO small and will need an adapter)
and will give a clean "Scratch" thru even the THICKEST of Etch resist
coating. The biggest obstacle will be sharpening the tip.

A little inginuity could figure a mount idea to fix a PCB drill bit
snapped short onto the shaft of the motor (using Epoxy or a small
piece of plastic as a coupler). The critical point will keeping the
bit balanced so it doesn't wobble with relation to the motor. On the
flip side the spinning of the motor should have a gyroscopic effect
to stabalize the motor in relation to the Pen mount to reduce wobble
in that regard.

I'm going to grab some motors Monday and try to fit in some
experiments next week. I don't have any suitable software for PCB
designs but for the purpose of the tests I'll use Corel to plot some
fine detailed text and lines. At least it'll confirm (or deny) the
concept.

There you go...more food for thought.

Thoughts.. ideas...other people's success or failures !!!

Cheers....Dean.