I recently received a Speedball kit that I tried once but didn't have luck. I was told I could use the sun to expose, which I did. Unfortunately it didn't work so good, my images were all blurry and a lot of the details got washed out. I'm convinced now I should have followed the instructions for exposing as stated in the book that came with the kit. It calls for a BBA no 1 photoflood bulb at 250 watts. Is this the best light to use?
Also, there's a ghost image left on the screen from my first attempt. I tried my best to scrub it off but it won't get off. It doesn't look like it's blocking any of the mesh. Is this normal?
Thanks Fred, I'm going to try the sun again. I'm in the SF bay area and have a terrace with great sun exposure. I'm a little confused with placing the glass on the screen or vice versa. My screen is 10x14 and with wood frame. If the glass is suppose to be bigger than the screen, how does it fit into it? if I place the glass on top, it's not going to fit into the screen and there's going to be a 1" space between the glass and screen unless you are referring me to place the glass underneath the screen.
Sorry if ive confused you more, I just want to make sure I do this the right way this time!
The sun is a fine exposure unit, the biggest problem is that it only functions when the sun shines.
I used the sun before upgrading. To use the sun, used 1 pieces of glass (bigger then the screen), plywood (same sixe as the glass, some black material and a piece of foam (the side of the inside measurement of the screen). I would tape the art onto the inside of the first piece of glass with the ink side facing up and on the outside edges of the glass i would put some strips of duct tape. Then i would place the screen on top of the glass. Next i would lay the black material over the screen and place the foam on the black cloth. Then the plywood was placed on top of the foam and compressed. Once compressed, the duct tape was wrapped over the back of the plywood. This formed a compressed stack, which was then taken out into the sun. After the screen visibly changed colors, i then took it into the shade and washed it out with a hose.
To the best of my knowlege, photo flood lights don't emit UV light. The options are either blacklight tube florecent bulbs.
Quartz light. Be sure to remove the UV blocking glass. (cheap be slow)
Metal halide grow light/street light.
Commercial exposure units also are metal halide, but use a feedback circuit to determine exposure time based on light units. These can have either the light below or above, depending on design.
Vacuum frames are better than compression frames.
fred
Thanks Fred, I'm going to try the sun again. I'm in the SF bay area and have a terrace with great sun exposure. I'm a little confused with placing the glass on the screen or vice versa. My screen is 10x14 and with wood frame. If the glass is suppose to be bigger than the screen, how does it fit into it? if I place the glass on top, it's not going to fit into the screen and there's going to be a 1" space between the glass and screen unless you are referring me to place the glass underneath the screen.
Sorry if ive confused you more, I just want to make sure I do this the right way this time!
I burn 20 x 24 screens with a bba no.1 photoflood at 17 inches for 22 minutes it works great, the glass should be on the shirt side the screen not print side, for 10 x 14 screens burn it at 12 inches , and try it for like 15 mins, that should work for ya, bba no1 bulbs are about 2 .50 a piece , cheap bulbs but average life is 3 hrs per bulb, good luck
For a beginner, nothing beats a commercial exposure unit. Nothing else is BEST. There are other possible ways, but BEST needs to be affordable, repeatable, and consistent. As a beginner using jury rigged solutions will just frustrate you. It can be done and if you have time and $$ you'll get it figured out. The money you THINK you are saving by not buying a commercial unit is actually wasted in terms of labor, materials, and frustration.
If you got a couple hundred bucks then get a good exposure unit, but for BEGINNER cheaper is usually better starting out, why waste the money on it if not needed right away. Is it a hobby or business? You got money? If so by the best stuff, if not make it work as cheap as possible!
10 dollar worklight with the glass removed. Many folks use them and it is as easy as it gets. I have mine clamped to the end of a piece of angle iron which in turn is clamped to a shelf that holds it about 18 inches or so above the image. 6.5 minutes with Ulano QTX. Easy and cheap.
Would I like to have a commercial exposure unit? Sure. Would it do a quicker job, probably. Would it make my exposures sharper? Not sure, but I have no complaints.
Eventually I will have a good vacuum unit, mainly to help with workflow, but until then I think I will be fine. The money I am saving now is allowing me to get going and put things like ink and other necessary things on my shelves.
"Best" is relative and very subjective and all the aforementioned info is cool. That being said, let's work with what you have at the moment so you can start having fun...
You were correct. You should have followed the directions in the book that came with the kit. I started years ago with the Speedball kit and actually used the method after I got a 4 color press and dryer. Back then it was 150 watt photoflood bulb with an aluminum pie pan reflector at 12" for 45 minutes. It worked...well. On sunny days I used the sun for 30 seconds. Should look like this...
Make sure your positive is very opaque to not allow light through the print image. Expose for the recommended time at the recommended distance and you should be good to go. Use a scoop coater to coat the screen if you have one. Minimize exposure to light (especially sunlight!) prior to burning.
As far as the screen reclaiming, underexposed/cured emulsion can be oft times very difficult to remove (true!). You might have to blast it out with a pressure washer. But if all the emulsion is washed out and not blocking the mesh you just have residual ink staining. You using waterbased ink? If so try bleach.
Oh, and the tiny print under "foam material" says to cover the foam with a black shirt to lessen light reflecting back up...
Last edited by TYGERON; November 16th, 2010 at 12:17 PM.
the halogen shop light that ryonet sells is simple and easy...Screen Exposure Stand as a matter of fact this is probably the easiest thing of the whole process for me ahahha... with a little inginuity you could probably make for for a few bucks... i burn this emulsion Qt CCI DXP (Pink) Diazo-Photopolymer Dual Cure Direct Emulsion, for 13min 30 secs and it comes out great. i try to limit my detail to a 9px brush at 300dpi what ever that figures out to be hahaha... (meaning when in photoshop, and working at 300dpi, i dont expect anything smaller than 9 pixels to wash out)
how was that for a plug hahaha... but seriously it works great
What's the best way to expose for a beginner? 
