PCB manufacture

[Stoney]

Hi everybody .. (hi Dr nick)

I wasn't sure which forum to put this in as there does not appear to be much mention of PCB etching.

I have been using pureetch for a few years, though very intermittently.

My current method involves ..

create design using the free version of Eagle PCB (size limited)
output as an inverted PS file
convert to a pdf using an online converter (i need acrobat distiller)
print using a cheap Canon i250 inkjst onto high res epson paper (coated on one side)
damp down the paper with baby oil rubbed into the back
expose with sunlight at 35 seconds or a sunlamp at 4 minutes 30

the whole process works well when the sun is out, but the sunlamp gives me problems with uneven exposure and also it seems to be hard to get a correct exposure where the pcb will etch cleanly.

the sunlamp is a small IR and UV output device, i think the UV lamp is a small high pressure mercury discharge lamp, it is in series with the IR heaters to limit the current.

my question regards exposure lamps, what is the best low cost method of consistent exposure, from a bit of reading here it sounds like a 400W growlight mught be my best option. The 'plates' I am generating are only of the order of 4 inches maximum.

I joined up with these forums to get some assistance so i figure it is only fair to share my experiences. I can probably help out with any electronics querys also.

[Cape Fear Press]

I recently tested a 500 watt halogen spot light with clear glass cover. With the bulb 18" away from plate, 5.5 -6 minutes makes a perfect exposure using a Stouffer to determine this. Check out my youtube video showing this:
http://www.youtube.com/watch?v=8WJn5YFANxU
Jennifer