Homebrew PCBs

On Thu, 3 Jul 2008, Michel Baguet wrote:

> hi guys,
>
> I got to the point where I can etch 6 mils traces and 32 mils vias with
> a 12 mils hole with inkjet paper.

First, I presume you're using glossy inkjet paper for toner transfer from
a laser printer.

If that's the case you don't need to muck around with transparencies.
Print both sides of the layout to your normal paper, place them together
face in - hold them to a bright light and use the vias to align. Suitable
bright lights are: the sun, a table lamp, or best, a light box where you
can lay it all flat.

Then tape the ends of the paper together at one end, to form a hinge.
Re-check that it's still aligned. If it is, slip the copper board between
the paper and get ironing.

I've done lots of double sided boards this way - never had a failure.