UV exposure box

[Zuse]

Could anyone tell me if there is a recomended layout and/or spacing for the UV tubes in an exposure box setup

[Herman the German]

Yes, I can do!

The film or whatever You use to expose Your future board likes parallel light very much and the more even the light is distributed over the entire board area the better will be the result. I built a box when I lived in germany (now Thailand, the no-have country) I used 6 fluorescent lamps Type TL29D16/09N and kept the spaces closer than 1 inch. Before I built the box I metered the light and gaps greater than 1 inch are absolutely the worst You can do to Your box.

15mm (1inch=25.4mm) is the best to do. You have the light almost parallel and enough room between the glas tubes for cooling. UV-A produces more heat than white light. If You use aluminum foil on the bottom of the box (not straight and even, just a little bit crunched) You will increase the reflections but don't do too much of crunching because reflections will penetrate the film slanted and that means unwanted exposure. Check the film side at the photoresist, closest contact. Printing on the wrong side has to be avoided under any circumstances.

Have a good time building Your box.

Best regards

Herman the German

P.S. I am about to build my box soon but this one will almost be unafordable in EUROPE since I will make it from Teak-wood (only used on ships and extravagant furniture)

[tyco]

Hello!
I am in the 2ND year at an electronics faculty, and i want to build my own UV exposure box. Unfortunately i could only find this UV lamps - BEL41017 15W/220V. Are they OK? What changes need to be made from the project in the articles section on this site?
Thank you for your help!

[Hero999]

Yes, that should be fine.