Homebrew PCBs

Hi russel: can you post some specifications and pictures of that reflector? Also, what was the largest board exposed on that reflector/lamp setup?
Thanks in advance!




--- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@...> wrote:
>
> > From: Jeff   Sent: Thursday, January 19, 2012 22:55
> > I see that some here are using HID mercury lamps for mask/photoresist
> > exposure. Where can HID mercury lamps be obtained? Do they give better
> > results than black lights or the yellow-housing halogen work lights found in
> > home centers?
> 
> I've been using a HPW125 for years, 800mm from the pcb and at the focal line of 
> a cylindrical parabolic reflector made from aluminium sheet. It gives good 
> collimated rays. I expose the precoated negative resist for 90secs with it.
> 
> It takes 5-10 mins of warming up for full output.
> 
> http://www.lamptech.co.uk/Spec%20Sheets/Philips%20HPW125.htm
> 
> >> DO NOT break the outer glass shell of a mercury vapour lamp! It will
> > radiate a lot of short wave UV (UV-A) which is dangerous for eyes and skin,
> > and it generates lot of ozone (O3). Good results could be obtained without
> > breaking the outer glass shell.
> >
> On 20/01/12 22:02, Boman33 wrote:
>  > I bought my HID lamp at eBay.  Remember to buy a socket too.
>  >
>  > I am not using it for PCB production since I have a 400W UV light source.
>  >
>  > Always use eye protection!
>  >
>  > By the way, breaking the protective glass on a regular mercury bulb lowers
>  > the UV output, not increases it. (The capsule will run too cold to be
>  > efficient.)
>  >
>  > Bertho
>