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

On Fri, 4 Jul 2008 09:47:55 +0100 (BST), you wrote:

I've always had a conceptual problem doing it exactly this way. I can
see that if the joint between the two pieces of paper is exactly in
the middle of the board thickness, every thing aligns. If it's not,
then one layer is offset with respect to the other.

Has anyone considered aligning the masks with a filler made from a
scrap piece of etched board, same thickness, and then perhaps a piece
of plastic to duplicate the board?

Harvey


>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.