Homebrew PCBs

I have a bag full of high output UV LED's.  These things are very strong, I
made the mistake of looking into one once.  I was thinking about putting
them in a cigar box covered in foil to make exposures of photoresist copper
clad boards.  Do you think this will work?  Ball park exposure time?

Thanks,
Chris Maness


[Non-text portions of this message have been removed]

I use UV LEDs for my exposure box - 100 of them, on about a 1" grid, 20 
mA, about 5" from the PCB.  Takes about 5-6 minutes to expose.

Mine uses 96 UV LED's (the cheap ebay variety) on a 15mm grid. Exposure 
is about 45-60 seconds at 6" using negative resist film. There is no 
need for foil. etc. as a reflector, just make sure your distance is 
great enough to even out the illumination.

Eddie

DJ Delorie wrote:

>
> I use UV LEDs for my exposure box - 100 of them, on about a 1" grid, 20
> mA, about 5" from the PCB. Takes about 5-6 minutes to expose.
>
>

What wavelength is photo resists most sensitive to?

Thanks,
Chris KQ6UP


[Non-text portions of this message have been removed]

On 17/04/2010 14:08, Chris Maness wrote:
> What wavelength is photo resists most sensitive to?

350 nm.

Leon
-- 
Leon Heller
G1HSM

Chris Maness pravi:
>  
>
> What wavelength is photo resists most sensitive to?
>
> Thanks,
> Chris KQ6UP
>
mine is 400nm
> ._,___