"Dave Plowman (News)" wrote in message
...
In article ,
Arny Krueger wrote:

"TonyL" wrote in message
...

One way is to make a transparency and use that to mask a board coated
with an emulsion then exposed to UV and develop. Then etch in the
normal way.

That looks the most likely option for me.

UV boxes start at around 70 UKP, though. Surely they are just boxes
with
UV bulbs and maybe a timer. Any reason I can't make my own box and buy
a
replacement UV bulb or two ?

Isn't the old light-sensitive resist still around?

Also, direct sunlight is loaded with UV.


You do need to use a reasonably accurate combination of level and time
though - like any exposure.

Not like *any* exposure. The "negative" generally is line art, thick black
over transparent film. Very, very high contrast. The "film" is designed to
be very tolerant of small exposures to light. It wants to produce a high
contrast "picture".

And the coated board is rather expensive to experiment with.

With the old stuff, I never ever missed the first time. After you do this a
bit, you end up with scraps to play with.