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Subject: Re: Still getting broken traces.

From: "sethkoster" <sethkoster@...>
Date: 2006-07-25

--- In Homebrew_PCBs@yahoogroups.com, "Myc Holmes" <mycroft2152y@...>
wrote:
>
> Hi Seth,
>
> One question, are the breaks always in one direction? In other
words, are
> they always in the traces that run in same direction, parallel to
the way
> the paper is printed?

Hey Myc, thats a good question and I'm not sure of the answer. I am
planning on waiting until the .032" boards I ordered from abcfab on
ebay show up and then retrying everything using the laminator.

>
> The broken traces sound like the paper is changing dimensions under
heat and
> the toner is not "stretching" along with it. I suggest you first run the
> paper through the laser printer without printing anything to give it
a "heat
> treatment" then reprint with the pcb pattern.
>

Hmm... It occurs to me that since I was moving the iron the very
same problem could have happened during the re-fusing phase. Perhaps
because the PCB is heating up and cooling down in areas as I move the
iron around it is exacerbating this problem.

> I'm using athe Samsung ML-2010, an earlier relabeld version, with great
> success,. The toner needs higher temerprature to fuse. A few extra
passes
> through the laminator works for me. Or else, after running it
through the
> laminator giving it a few touch up strokes with a hot iron.
>

I went to the University of Michigan Property Disposition (I love that
place, if I ever need a cheap used DNA sequencer or Gieger counter I
know where to go) today and picked up a used HP LaserJet 5 in pretty
good condition for $50, though its low on toner (yet it printed pretty
nicely when I used the test menu). Luckily I was able to return the
Brother HL-2040 and hopefully now that I have proven equipment I can
focus on my technique problems.

> Also. after removing the paper, flash fuse the toner using a a hair
dryer
> very close (1/8") to the pcb.
>

I'll give that a shot.

Thanks.