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Subject: Re: Re: Toner transfer experiments

From: Richard <metal@...>
Date: 2006-02-08

Bill, I'll be interested to hear the difference you get
in readings using the heatsink. I like the optical thermo's,
but one has to be careful to -understand- how they
work; and use them accordingly.

We've used them up to 2,000F or so, in checking
induction-heat cycles for heat-treating of parts. But
one has to have a good quality emissivity chart for the
materials, and temps, actually being measured; in order
to get meaningful results. Our in-house lab did a series
of tests in order to make the E-chart that's used on the
floor.

Your idea to -preheat- the board in the oven was an
excellent one. It is no surprise that it helped your
results enormously. Considering the residence-time
under the rollers of any particular spot of the board,
it would take rollers with pretty good thermal-mass
to heat the copper to 400F in that very short time.

Probably why the $500 laminators work well; and the
$29 lams do not... <g>

re: Typewriter rollers: I wouldn't even try it. Not any
black-rubber rollers. The rollers in laminators and copier
/ laser-print fusers are -silicone- rubber...good to around
450F. Totally different kind of material than black rubber.

R.
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