🚀 go-pugleaf

TO: ALL

I've seen several messages posted here concerning printed circuit board
fabrication, and am interested in hearing other opinions and experiences
from people who have tried one or more of the various methods.

I am particulary interested in the direct toner and reversal film
methods (Datak), but I will entertain any other methods.

So far, I have tried two of the direct toner methods. One is called
press-and-peel (P-n-P) sold by Techniks. It is supposed to be an
improvement over the original TEC-200 film, but I can't say that for
myself since I haven't tried TEC-200. The P-n-P film has a special blue
coating which acts as a release agent and toner strenthener. I've had
mediocre success with this film, but if the time, temperature and
pressure factors are optimized, I suspect I can achieve a much higher
success rate. I've been using a clothes iron to make the transfers, but
I am considering purchasing a heat press. They are hard to come by and
are expensive in my area (NYC). Problems I have encountered: not all of
the toner transfering (too little heat/ time/ pressure ?), smudges or
hourglass pads/ traces (too much heat/ time/ pressure ?). I think
optimizing these factors will be easier with a press.

Another method is the new Toner Transfer System that is advertized
in Nuts and Volts and also sold by DC Electronics. I've purchased 5
sheets and tried several already. This is a paper rather than a film. It
has a sugar coating on one side. You iron the pattern on as with the
other films. The toner adheres to the water soluble sugar base as
well as the board and, you guessed it, bathing it in a warm bath
releases the paper and leaves a nearly perfect pattern on the board
ready for etching. Minor problems with this method: traces and lines
spread out and toner is very brittle after transfering. Both problems
are related to heat/ time/ pressure factors. I prefer the former
method, however, since the transferred pattern is more rugged and can
be repaired if a trace is missing, eg. Also, the P-n-P film is less
expensive (10 sheets for $5 vs. $10 for 5 sheets of the sugar paper.)
The press will solve most of these problems.

Another method I'm going to try is the Datak pos-neg process. This is
more involved and time consuming (far less than sending it out), but it
can produce more precise patterns on the board.

I am planning to build projects using SMT devices and will use the
pos-neg process for SMT, and P-n-P film for TTH designs, unless I can
achieve accurrate transfers (SMT fine pitch) with the P-n-P film.

Anyone else have PCB fabrication experiences they would like to share ?

Chris