Another exposure unit question

The soft or rounded edges will come from light creeping in around the edges of the art....which probably means that you need better contact between the art and the screen. Do you have a piece of plywood wrapped in a soft cloth, or something like that, which fits the full inside dimensions of your screen? Without a vacuum blanket you definitely need that at a minimum, I would say. Just making sure there is enough weight on it to keep it flat.
Shouldn't need to decrease the distance between the bulbs unless you are seeing some 'banding' on the screen (less exposed in the spaces between where the lights are).
Re: bulb distance from the glass.....I have it set somewhere between 2-2.5". This was the recommendation and it works great.
One other thing....as you progress, try to find a more transparent solution for your artwork (film). This will drastically reduce your exposure time and the problems associated with it :] Less time = Less light creepage.

One more question, is it safe to look at or be around unfiltered black lights for extended periods of time. The reason I ask is because I was considering using my exposure unit as my light table for tracing as well.

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Originally Posted by brycimus

One more question, is it safe to look at or be around unfiltered black lights for extended periods of time. The reason I ask is because I was considering using my exposure unit as my light table for tracing as well.

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You wont be able to use blacklights for a tracing table. If the UV radiation doesn't get you then trying to see what you are doing under blacklight certainly will, but perhaps you are squinty to begin with.

sand the UV off the bulbs first.

I have seen people place two sets of bulbs in a table to make the table multi-surface. That could work.

I have two regular flourescents in there as well, on a separate switch. Works great. Electrician friend :]

So I'm planning on building a vacuum lid for my unit and I'm researching the best places to get stuff. I have 2 questions

1. What thickness neoprene do I need? I've seen people say 3 & 4 mm. Has anyone ordered from foamorder?
2. In terms of vacuum pumps, will something like this do? Vacuum Pump - Amazon Then I would just need the hose for attaching to the blanket/lid?

In a pinch (before you build the vac frame), you can stack phone books on top of the screen. Lay the film down on your exposure unity (or tape it to your screen), place screen print side down on the unit (as per usual), lay a piece of black paper or fabric down on the squeegee side of the screen, then place the phone books down. This works like a charm.
Also, those vacuum space bags work too. Put a flat block of foam on the squeegee side of the screen with the film taped to the print side. Put the whole thing in a space bag and suck it nice and tight. Then lay it face down on the unit and expose.

Don't know if you ran into this on the forums, but this is one I made a few years back –*it's still going strong, and the price was right. http://www.gigposters.com/forums/scr...-20-bucks.html

When I built Mine I used Foamorder. I've used 3 and 4 mil and def like the 4 mil better. I get it black, with plain backing. You may be able to find some 4 mil cheaper online, I was just lazy at that point. I bought the vacuum pump of ebay I think, but make sure you have a way to power it. It took me forever to find a proper adapter since I had no clue how to hardwire it and almost blew the pump up first try. I added a switch for the vacuum pump, a used digital photo timer and two banks of regular lights for using as a lightbox (doesn't work as great as a real lightbox). Here is shot before I added the vacuum blanket.http://img163.imageshack.us/img163/5008/exposure.jpg
Last think I would like are some of those hydraulic things, like for your car trunk, so I can keep the lid open. I just don't know where to get them.