Hello All,

I use 3 Phillips TLD 15W/05 bulbs in a home made fixture that has an
exposure area of 12" x 18" (45.7 x 30.5 cm.)  spaced 6" (15 cm.) below
the exposure surface. I ran 3 - 1.5" x 3.5"  (8.9 x 3.8 cm.) pieces of
wood through the table saw at an angle to cut a parabolic shape in the
wood pieces the length of the lamps. Then I glued foil to the parabolic
surfaces for reflectors. The lamp fixtures were some low priced 15W
florescent fixtures that I used for parts.  I place the film
(transparency) on the glass surface, the circuit board on top emulsion
side down with a piece of foam rubber on top,  then a lid (painted flat
black) to hold the sandwich of glass, transparency, board and foam rubber
together. Makes a light tight package to keep UV out of the eyes and hold
the board in contact with the transparency.

I get very consistent exposures this way (2 min. 25 sec.) by using my
darkroom timer to control the exposure lamps.  I like this as there are
no wasted boards. I use transparencies produced by an inkjet printer for
all of my in house boards. Otherwise it is Gerber files to the board
house.

Vern



Jinx wrote:

> > >I use an old Philips half-body sunbed (or whatever
> > >it's called in english) for the exposure.
> >
>
> Alan B. Pearce wrote in sunblock on his leg
>
> >
> > (shouts over shoulder) "Sorry darling, I'm using the sunbed today,
> > it's printed circuit board day" :))
>
> Ay-oop lad, surely thas don't need t'sunbed in north of England ?
>
> "Sitting in an English garden waiting for the sun
> If the sun don't come, you get a tan from standing
> in the English rain"
>
>

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