Derek,
Using a template or stencil is basically like silk screening.
With silk screening the silk is covered with a light sensitive
chemical. A negative is put against the silk. After exposing the
silk to light, it is developed. The silk allows ink to flow through
the image.
The group wants to print right onto the copper from some kind
of printer so the board only needs to be dropped into the acid.
John
--- In Homebrew_PCBs@y..., "High Tech" <hightechsystems@a...> wrote:
>
> Hi Everyone,
>
> I have been thinking about this for a while and I haven't seen it
mentioned
> before.
> There are many ways to get your idea to copper one I have not seen
is
> TraceTemplate(TT), for those who have a CNC machine such as
Crankorgan, I am
> still working on my second one.
> Basically milling out the entire traces of the circuit in a TT and
spraying
> an etch resist on the pcb. The only thing is you will not have
center hole
> in your pads it will be solid copper unless you get very creative.
You could
> also make a second or third TraceTemplate for ground planes.
>
> This only requires a few steps;
> 1. Draw the circuit (CAD,Eagle,ETC or by hand)
> 2. Transfer the drawing to G-code
> 3. Mill a TraceTemplate in plastic, PCB or whatever
> 4. Hold TT against the PCB (clamp together)
> 5. Spray with a Etch resist such as laquer,possibly paint
> 6. Etch
> 7. Remove the resist
>
> The beauty of this is once you have done steps 1-3 all you have to
do for
> mass production is steps 4-7. Multiple boards can be sprayed at
once.
> 2-layer boards would be easy with reference holes and you could
spray both
> sides at the same time. This is going to make it easy to make large
> quantities of PCBs for very little money and it will come out the
same every
> time. Can't wait to start making my TraceTemplate.
>
> Derek B.
> High Tech Systems
> Denver, Co.