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

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Subject: Re: [Homebrew_PCBs] H2O2 Sources

From: DJ Delorie <dj@...>
Date: 2008-09-17

Harvey White <madyn@...> writes:
> Still using FeCL3. Still muttering about how to get the boards
> registered properly, I've done both photoetching and toner transfer.

Registration with photoetch is a LOT easier than with toner transfer,
because you can see through the plots. I add a few registration marks
on my plots, pre-drill the boards for those marks, and just visually
line up the plots with the holes. Works every time, and easy to do.

The trick is that you need to design a registration mark that results
in a fine-line crosshair in the final plot. Since I use negatives,
this means my boards have four copper squares with about 1 mil between
them, resulting in a 1 mil ink crosshair on the final plot. I line
that up with a 13 mil hole. I expose one side at a time.

To drill the holes, I just print on plain paper and drill out each
crosshair.