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Subject: TT minimum line width

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2007-01-17

As promised i tried a test pattern.
I had not much time to think one up so i made simple grids with the lines
extended on two sides.
The grids are equal line/spacing, 2/2mil, 3/3mil, 4/4mil and 5/5mil.

I noticed that the printer (600dpi, sold to me as 1200dpi which is really
only a lie) did not do very well with this test pattern. It could not keep
the lines at equal distance, and of the correct width. When one is making
such test patterns multiples of the printer pixel size should be used
instead. So mainly this shows how bad the printer is.

Nonetheless i etched it, in CuCl, with somewhere under 1 mol of HCl
content, reasonably regenerated. The transfer was done with Verbatim
glossy photo paper using a fuser, i think at 180C, single pass.

Here you can see the result:

Transfer:
<http://tinypic.com/view/?pic=4gpjwy0>

Etched:
<http://tinypic.com/view/?pic=4g86mw5>

I'm sorry about the quality but it is all my scanner will provide. If i
find the time i will attempt to use the digital camera possibly through
the microscope, if that works.

More or less all it shows is that 5mil is the limit with a 600DPI printer,
below that lines will break up too easily. Also, 4 mil and under is always
the same line with for the printer.

The other board i made today uses 10mil/10mil minimum throughout, and a
little less spacing in places, without a single fault. 10mil is what i
would use any time without much thinking about it.

ST