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Subject: Re: UV exposure box

From: "Ben L" <bhleavi@...>
Date: 2010-02-14

> Barry Demers <sdad@...> writes:
> > I have been using a single bulb 12" from a 6 x 9 board, with a 24
> > min exposure.
>
> A single 15 watt bulb?
>
> I've been pondering upgrading to two-sided UV exposure, but my LED box
> exposes in only 5 minutes.
>
> Can you reduce the exposure time by using mirrors to reflect more of
> the UV light to the board? I.e. something behind the bulbs, or the
> sides of the box. Or is it just going to mess up the quality of the
> exposure?
>

I have 4 15 Watt 18" lamps and do upto 8" x 12" boards at about 6" from the lamps. Use to expose about 6 mins. but now have found that 10 mins is better as long as you have a really good transparency.

Now that I am using Dip Trace instead of the old Ivex Winboard I get a lot better printouts onto the Transparencies. Seem to get a lot more ink down printing from Dip Trace than I did from Ivex Winboard, even though I would set the amount of ink to max in the printer settings. With Ivex Winboard I had to always double up or try to print it twice which did not always work.

Ben