I use a 500 watt halogen "work light" from the hardware store, $10
including an extra bulb stashed in the handle. I also use this chinese
dry-film resist (ebay, $40 for way more than I can use before it dies)
fed through a $25 laminator from walmart, using the procedures noted at
thinktink.com. My contact frame is an old glass-faced photo contact
printer, a couple bucks at a thrift store but generally available cheap
on fleabay.
With the UV-filtering glass and guard assembly flopped out of the way I
get a good exposure in about four minutes at ~18 inches. I also avoid
eyeball exposure, I figure that UV filter is there for a reason.
I generally only do brass, not copper pcb, and I have a darkroom so I can
go from a good dark inkjet print to litho film without too terrible much
trouble. I ∗have∗ used an inkjet print as the mask (oil the paper with
vegetable oil, let soak a while, then keep wiping until dry-ish), takes
about twice the exposure and requires testing - produces slightly rough
edges. I'm going to need to make a pcb or two soon, so I expect this
experience will come in handy.
-Gary
> Can someone please recommend a UV lighting source which:
> - is cheap
> - has consistent UV output
> - is readily available, or easily made up from items from general
> hardware stores
> - gives good results with low exposure time (preferably 5-10 mins,
> I'm not keen on 30 minutes)