Re: Building UV exposure unit (was Re: new to list)

Bulb to paper distance is 2 1/4" in my exposure unit. I don't think this
dimension is very critical. The bulbs are spaced close together, there's a
1/2" gap between them. It always produces very even and consistent
exposures.

I did not install a ventilation fan on my unit, and I've never had heat
buildup become a problem. The ballasts are mounted on the exterior of the
unit, so that helps keep it cool inside. I also drilled (4) 1 3/4" holes in
the sides of the unit, for ventilation.

My exposure unit is mounted on the wall of the darkroom, requiring very
little space. There's a homemade vacuum easel hinged onto one side of it.
It's very fast and easy to load and use.

Dave in Wyoming

----- Original Message -----
From: "Christina" <darvida@gmx.at>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Wednesday, November 03, 2004 9:49 AM
Subject: Re: Building UV exposure unit (was Re: new to list)

I will build one this weekend....got the whole stuff here.
If I´m finished I will show the workingprocess on my homepage if anyone is
interested.

I will use 8 UV-Bulbs á 8W and a fan to cool it.
Yours Christina

P.s. can you tell me the distance paper-bulbs that you use?

-----Original Message-----
From: Dave Rose [mailto:cactuscowboy@bresnan.net]
Sent: Mittwoch, 3. November 2004 17:09
To: alt-photo-process-l@sask.usask.ca
Subject: Building UV exposure unit (was Re: new to list)

Welcome to the list.

If you're handy with tools and able to design & fabricate, building an
exposure unit is an easy weekend project. Construct a wooden box to hold
your bulbs and bulb sockets. 1"x6" boards with a thin plywood backing works
well. Position a large piece of sheet metal immediately behind the bulbs -
otherwise they won't turn on. Go to a electrical supply house to buy the
bulbs and associated hardware.

My homemade exposure unit has (8) Sylvania F20T12/350BL flourescent tubes in
it. Exposures range from 1.5 to 8 minutes for gum, and 5 to 15 minutes for
cyanotype.

Best regards,
Dave Rose
Big Wonderful Wyoming
Received on Wed Nov 3 17:54:16 2004