On press - Spot in the design

[Screened Gear]

My guess is the light doesn't harden the emulsion on the squeegee side like it does on the shirt side.

Yes, I use the glisten method.

Makes sense.  What exposure unit you running?

I use a window squeegee to swipe off excess water from the screens right after spraying them out.  Then I hit them with compressed air and put them in front of a 42" fan.  We rarely have any scum in our image, but it can happen with all the things we do to prevent it.

I also use air to blow the water out of the image area before putting the screen in front of a fan. I almost never have unexposed (clear) emulsion in my designs. If i do have some it is so thin one print will clear it out.

The spot Gun clears the spot in no time.

[ebscreen]

Can't recall the last time we had scum, but once a year or so we will  have a piece of unexposed emulsion
as described. Like a pinhole in reverse. Typically from a piece of dust on the film that the inkjet didn't cover,
etc. Spot gun works and that's what we did last time. Scared me half to death, had 6 other
discharge screens already setup.

[Printwizard]

I think the spotting gun advice is dangerous.  I don't know depending on brand, but our gun will blow the emulsion right off and perhaps even hole a tight fine mesh screen. If its in the middle of a big area away from the edge, say 5mm off then fine, but if it's close in the image we have blown the emulsion off, then it's a case of trying to tape the screen area and squeegee emulsion back with a credit card to repair the blasted off area.  Pays to pay more attention in stripping, degreasing, and washing out properly.  If its an old mesh coarser screen we would pin it.  Remember the best way to fix a problem is to know what caused it, why, and avoid the effects of that in the first place.

[mooseman]

we have this issue every now and then. We actually take a toothpick saturate it with emulsion remover ( we use Frannar stripee- doo) and dab that on the unwanted spot,  while on press, let it set for a bit. Sometimes pick at it carefully with the toothpick to help the stripper do the job. Next  a wet cloth to remove it. Works every time the trick is not to overload the emulsion remover just put it where you need it then use plenty of wet from the towel to get it out. working close to an edge you want to keep we apply some thin tape top & bottom to restrict the emulsion from wicking where we do not want it to go.
Sounds like trouble but it works for us and only takes about 5-10 minutes and we are good to go.

[sweetts]

Ours is backwards, it's not safe to rub the squeegee side, the shirt side is fine.<br /><br />The thing I like about my method is I toss out less paper towels.  I hang them and let them dry.  Blotting them when wet, they get really crispy.<br /><br />A good rinse on the side the wasn't facing the light also cuts out most, if not all scum, but sometimes this step is missed or not done 100%<br /><br />Speaking of all of this crap, I have around 60 screens that I need to untape and reclaim.  I am playing around more with liquid tape since I am spending over $600 a year on tape and just wasting it frankly.  It get used for a day and then tossed.  Not to mention the time involved in taping and untaping.  Even if it's 5 minutes a frame, that's huge.  That would save us around $100 a week in labor and tape(quick estimate).

I have been thinking of the same

Sent  from samsung gem(the worst smart phone ever)

[aauusa]

my rule of thumb is if screen opener does not get it out then spit on it and i will guarantee that spit will clear it out. if spit is to gross then use some water on a rag.

[chubsetc]

I have some plastisolve spray from ryonet, not sure what it is but it basically dissolves uncured plastisol.  I have it sitting near the dryer is case a shirt folds over on the print when pulling it to place it on the dryer.  A little of that stuff on the corner of a napkin will remove exposed emulsion dots on a screen without the possibility of damaging the mesh with the spot gun.

[jasonl]

spot gun rules for this problem!  been doing it for 14 years.

[Frog]

Along with your spot gun, something like this can come in handy, as it does when blowing out a shirt as well.
A stainless steel eraser shield should be available in an office supply store.

[Itsa Little CrOoked]

That's a great idea, Frog!  That coupled with the spot cleaning gun looks like a workable solution.

@ Mooseman, I never thought about a toothpick, but I use a Q-tip and sometimes reclaimer goes where it isn't wanted. Seems the toothpick would be better when there isn't much open area to work with.  I only have a handful of these scenarios each year, but this thread has some good ideas I'll have to try.

I know its just dreaming, but I just wish there were a way to reconstruct a missing dot or two, caused by a goober in the emulsion that flubs up halftones! That is somewhat more common in my shop than the specific topic of this thread. I've been using tack rags on screens I'm coating on windy days. In my mind, I think that picks up a lot of lint, dust, etc that causes me grief on fine work....but that's not really the subject of this thread.

[Prosperi-Tees]

Great ideas here that never crossed my mind. I usually just burnt a new screen. Also the tack cloth idea I'm gonna have to try as well.

[Itsa Little CrOoked]

Gerry, move quickly with the tack rags, and with light pressure. Just don't let the cloth sit in one spot any length of time, as it could impart enough of the "tack" to the mesh to cause a problem. And I only do it in dusty conditions, or if the screens have sat out any length of time. A clean, filtered drying cabinet would be a better solution, but my shop has some unique challenges.

[Prosperi-Tees]

We have our own challenges space wise not to mention my neighbor is a cabinet maker so there is always dust. One day I will have a proper darkroom.

[Itsa Little CrOoked]

Okay, so you ARE a candidate for tack cloths. I buy the ones in the paint dept at  Walmart, and put them in Ziplocks or Mason Jars when finished. It sticks to my hands, especially when freshly opened, so brushing them very lightly on the mesh seems prudent. I'm sure some contaminants would be transferred to the mesh if used with a heavy hand. I always thought sometime I'd use my technique on a clean window, and watch to see if it was streaked with contaminants, but I've never gotten around to it.

I'm kinda bad about hijacking threads, but I don't mean to. Sorry.

[Prosperi-Tees]

Thanks for the tips, ill pick up a tack cloth and try it out, heck maybe my neighbor will give me a new one! lol.

Back to this thread, I need to adjust my exposure times because I am started to get some diazo rinsing off when washing out. I have started coating most of my screens 2/2 with the round edge and my 240 watt blacklight unit is going to be working overtime. I am at 7 minutes on a 110 or 156 and need more. I know I know an exposure test is needed.