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Subject: RE: [Homebrew_PCBs] Direct Toner - First Try Results

From: Mark Lerman <mlerman@...>
Date: 2008-04-03

Bertho,

I wouldn't have thought that opto interruptors would be that
repeatable. I'm going to run a sheet of paper through a laser printer
twice and see how well duplicate images register - a rough measure of
what's easily accomplishable.

I just bought a pid controller - going to put it on a hot plate and
see what happens. Or maybe an oven? Which is better for smt soldering?

Mark


At 10:45 PM 4/2/2008, you wrote:
>Hi Mark
>
>Keep up your excellent work!
>
>This is a very interesting application! In addition to Robert's comments on
>the opto interrupter accuracy here is a link to an accuracy evaluation of
>them:
>
>http://www.vinland.com/Opto-Interrupter.html
>
>
>
>As for laminator issues, I think getting away from it and using a controlled
>melt will long-term be much more preferable since the laminator inherently
>tend to counteract what we want: Narrow accurate lines. Applying pressure
>to molten toner is asking for it to widen and possibly smear. It is
>difficult to get both pressure and temperature reliably and repeatedly
>controlled at the same time.
>
>Bertho
>
>
>
>
>
> From Mark Lerman Sent: Wednesday, April 02, 2008 19:32
>----<snip
>I used a precision optical sensor to find the leading edge of the
>board as it enters the printer. I wonder if I can make double sided
>boards with adequate registration? For now I think I'll stick with
>what I have. A double sided board can easily be made using thinner
>board and gluing two boards together using registration holes and pins.
>Mark
>
>
>
>[Non-text portions of this message have been removed]
>
>
>------------------------------------
>
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>
>
>