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Subject: Re: Home PCB kit

From: "Phil" <phil1960us@...>
Date: 2005-02-05

--- In Homebrew_PCBs@yahoogroups.com, "Thomas P. Gootee" <tomg@f...>
wrote:
...
> But yes, I DO have problems with toner spreading. But I usually
EITHER use large-enough spacings for trace separation (2/300ths-inch
seems like about the minimum, to have basically no worries about
developing a short between two 2/300ths-inch-wide traces), OR only use
1/300th-inch spacing where it won't really matter too much if a short
develops, such as when I have several parallel traces that all return
to a common ground point, which might have small (1/300th-inch)
spacing when they are getting close to their common connection point.
(Gee, I almost hope that someone asks me WHY I would want to run
multiple ground traces, in parallel, when they're all going to the
exact same place, anyway; heh heh.)


I had toner spreading (AKA trace bloom) problems when using heavily
coated papers. Using less coated paper such as ink jet paper seemed
to solve the problem for me (or at least, control it). It appears
that the excess toner is being absorbed by the paper rather than being
squeezed between the clay coating and the copper. Also, controlling
the amount of toner helps somewhat with the coated papers - I use a
copier so I can tweak the toner level to what ever I want.