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

Hi guys,

From this ground I have learned about toner transfer and PCB making
and have been doing it for a couple of years now. Recently, I have
been starting to work more and more with surface mount components.
As they are smaller and you can fit more stuff in the same space, I
am finding that I want to use traces that are more narrow than I have
been doing.

I am about 85~90% reliable with my current process doing traces that
are .015" (380 microns). I would like to get down to .008"~.010"
(200 to 254 microns).

Most of my current failures with narrow traces are in getting the
toner to stick and I think I can improve that part of the process (I
just started using a laminator instead of a clothes iron).

I etch with Ferric Chloride and bubbles. I am wondering wherein the
limit is there with regard to narrow traces. I recall a long while
back that there seemed to be a certain barrier where the trace width
was so narrow, "under etching" would cause breaks in the traces.

Anyone one care to share some experiences with narrow traces and DIY
processes?

Also, I am not opposed to using PCBs pre-coated with etch resist if
that would improve results.

Thanks

Chris