emulsion problem

[ToddFuller]

Like others I am not positive where my question really belongs so hopefully someone can point me in the right direction. Let me start by saying...please do not laugh!!! My mom and stepdad purchased a YUDU screen printing machine to give me a little hobby to play with at night. (my husband passed so life gets pretty boring at night) ANYWAY....After 4 1/2 years I have gotten up the courage to try it out. The first time I made a disaster of coating a screen, the second time...well I still had more bubbles than an aquarium, but fewer than I had the first time. Below is the first screen I successfully coated and burned. I know it's not great, but hey you can tell what I was going for. NOW however I am having some weird things happening. My screens SEEM to burn okay, but when I wash them out (so I can see my design) the emulsion gets very tacky to the touch and almost looks runny but my design holds fine. I don't recall it doing this on the first screen, but maybe I am just rushing the drying process after burning my screen. Maybe I shouldn't use the sprayer on my screen to expose my burnt image. Any tips would be greatly appreciated. I feel like my designs are burning okay, but they aren't printing as well as that very first time.

[ToddFuller]

I am using Dual Cure Emulsion I got (Again do not laugh!) from DIY in their Hack the YUDU kit. Again please don't laugh. My goal is simple...put more money into the charities and causes than I am putting into team and awareness shirts.

[Saati]

Honestly.....Getting the image to wash out /right exposure is probably the most critical part of the process. I find it funny how no one ever uses a exposure calculator. They are under 20.00 and will solve sooooooo many problems.

http://www.youtube.com/watch?v=5UPRYQY7P2M

To answre your question it looks like you have an uneaven coating of emulsion, so you may have enough exposure in some areas to harden the emulsion but in other areas it is under exposed (so it is leaving residue behind that is still tacky untill dried).

Dont feel bad If every shop had one of these little strips I probably would have a lonly life (like the matag repair man). You are not the only one who does without one of htese little devices.

[ToddFuller]

so perhaps then with time and getting comfortable with the scoop and screen I might improve then?? If not I think I am back to paying you guys for my awareness tee's.

[Shamax]

Welcome to the forums!

I'll second what Saati said. with practice, you'll get a rhythm and feel for how much emulsion you're putting on the screen. Also, if you look at your scoop coater, one edge of it should be fairly sharp and narrow while the other is slightly thicker and more rounded. The more rounded edge will give you a slightly thicker deposit of emulsion on your screen (that's the side I always use). Just make sure your screens have had time to dry before you expose them, and then once you washout do a little post-exposure to harden the emulsion that's left. I still get tiny streaks in mine from time to time, but it should affect your prints.

It seems like you have your base exposure time dailed-in pretty close, but any time you want to test it out, print out a multi-step exposure film like the one here: http://www.anthemprintingsf.com/Screen- ... -s/216.htm

Follow the instructions there any time you're not sure how long you should be exposing something for. Then, once you have that, do like Saati recommended and get a little 21-step wedge "calculator". I have one of Saati's and use it on almost every screen I burn. It lets you see how consistent of a burn you're getting and allows you to dial your time in even closer as needed. Plus, once your emulsion starts to get old or if your light source is getting weaker, a 21-step wedge will point that out, depending on which "step" it washes out to.

All in all though, you've got some great results so far - better than my first few attempts at getting screens made with a dual-cure emulsion

[ToddFuller]

Thanks Shamax! I have now printed 9 tee's and found by the time I got to the last 5 I was getting the hang of how my squeegee pushed and deposited the paint as well as how much ink I truly needed to be using. Some of my designs were pretty light, but I was terrified of using too much paint and losing the detail or getting smudges. Once I realized the angle my squeegee needed and pressure I was able to do more coats and get the richness I was looking for without blowing out my lettering. Will post a pic soon. Now a little less nervous about doing the fronts of the shirts!! Oh...I thought about hitting the emulsion one more time with some light after I washed out the image just to really burn it in, but than panicked I might burn it too long and ruin the screen...how long of a second burst you think I can go to?

Thanks again for not laughing at me and being kind...whole new appreciation for all that goes into screen printing. There isn't an unimportant step in the whole process, from design all the way thru...Kudos to those of you who have mastered it!

[drew]

After washing the image out, all your really doing is hardening the remaining emulsion. I usually will set the screen out for 10-20 min in the sun to post harden and let it dry quicker. I haven't had any issues with reclaiming after that amount of time. Could probably leave it longer. I haven't tried to put a screen back on the exposure unit to post harden.

[ToddFuller]

Thanks...I think I am panicking cause I have noticed that I have three very tiny dots of emulsion I cannot get out of the screen. I have a walk this coming week so thankfully I have been able to position my image where the dots of emulsion will not interfere, but frustrated cause they shouldn't be there. Saw where someone mentioned taking their screens to the car wash, but not sure the yudu screen could handle that kind of pressure and not sure at this point it would do any good. Looks like screens run around $25 bucks so that isn't terrible, but want to make sure I won't continue to develop them. Thanks again for all the support and I am happy to announce the nine shirts I printed turned out pretty good. I can see a tremendous difference in the first 5 v/s the last 4. It was obvious I found my comfort zone with the amount of paint and squeegee angle. So feeling a little better about all of it!

[ToddFuller]

It's not perfect, but I am happy with it! I read that it was important to let the ink really dry, so I have let these hang dry for 3 days now and will print the images on the front tonight or tomorrow and then let dry another couple days and then iron with a cloth between the iron and designs. Hopefully they won't fade or crack.

[drew]

If you used plastisol ink, it will not dry until the ink is heated to 330 degrees. I would hate for the shirts to get ruined, they look very nice! Do you have a flash dryer or a heat gun?