#126 PCB article
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> 3. ALL glass is essentially opaque to UV - transmissivity is
> very small! So
> are most plastics. Plastics generally available are subject
> to "crazing"
> when exposed to UV. With the exception of window glazing, of
> course. So this
> type of UV light table is depending on the small amount of UV
> that gets
> through. Note that all materials inside the box subject to
> the UV radiation
> will undergo aging at an advanced rate.
I'll have a close look at my UV table. I wonder if the white paint I used
will help reflect UV from interior surfaces, thereby help to protect them
from aging?
> 4. Can the author identify the particular UV tubes used? Most
> of them have
> identifying labels at one end or the other. Where can they be
> obtained? A
> lot of readers could use this information.
I'll look up the tubes again. As I recall, there is no manufacterer listed
on the tubes, just a number identifying the tube's length and that it is an
unfiltered UV lamp.
> 5. Addition of a simple wind-up timer in the power circuit of
> the UV table
> would greatly simply exposure timing.
I was thinking about that. i know you can get them from enlargers used in
darkrooms. It does add an additioanl cost, though.
> 6. The author's idea for scoring the PCB material is a good
> one. A standard
> glass cutter can also be used, but make only one pass
> through the score -
> additional passes tend to dull the cutter and gum up the
> rotating parts,
> particularly on glass-epoxy boards.
Ummmm.
I use to make some stainglass, I wonder if I could dig out the old cutter.
Thanks for the idea.
Paul
> very small! So
> are most plastics. Plastics generally available are subject
> to "crazing"
> when exposed to UV. With the exception of window glazing, of
> course. So this
> type of UV light table is depending on the small amount of UV
> that gets
> through. Note that all materials inside the box subject to
> the UV radiation
> will undergo aging at an advanced rate.
I'll have a close look at my UV table. I wonder if the white paint I used
will help reflect UV from interior surfaces, thereby help to protect them
from aging?
> 4. Can the author identify the particular UV tubes used? Most
> of them have
> identifying labels at one end or the other. Where can they be
> obtained? A
> lot of readers could use this information.
I'll look up the tubes again. As I recall, there is no manufacterer listed
on the tubes, just a number identifying the tube's length and that it is an
unfiltered UV lamp.
> 5. Addition of a simple wind-up timer in the power circuit of
> the UV table
> would greatly simply exposure timing.
I was thinking about that. i know you can get them from enlargers used in
darkrooms. It does add an additioanl cost, though.
> 6. The author's idea for scoring the PCB material is a good
> one. A standard
> glass cutter can also be used, but make only one pass
> through the score -
> additional passes tend to dull the cutter and gum up the
> rotating parts,
> particularly on glass-epoxy boards.
Ummmm.
I use to make some stainglass, I wonder if I could dig out the old cutter.
Thanks for the idea.
Paul