On press - Spot in the design

[Screened Gear]

You ever get the screens all set up and registered then you notice a small dot in a letter. Its not coming clean with press wash, screen opener, emultion remover or anything. Its just a little dot of emultion or something. I get one maybe 2 to 3 times a year. Instead of burning a new screen grab your spot clean gun. It will clean it out in no time and I have never hurt a screen. Just saved me this last week on a rush job that had 3 or 4 spots.

[Printficient]

Also spit will work.

[Fresh Baked Printing]

I really gotta get one of those guns.
I've also used a pin to perforate the dot. Usually not an issue with a 110 or bigger but anything finer can be annoying.

[mk162]

That explains why sonny is always licking the undersides of screens when he comes in here. 

[Sbrem]

If we're talking emulsion haze, spit is indeed the answer. I've never had it not work on emulsion haze. If it doesn't work, it's not emulsion haze. I recommend a little spit on your index finger and rub it out, as opposed to actually licking the screen. But, what you do in the privacy of your  own shop...

Steve

[mk162]

I have gotten in the habit of using a little mean green diluted way down to wipe my screens before they go on press.  It clears out any possible haze.  I'd say that maybe 1 in 10 screens have it, but once ink is in, it's a lot harder to get it to print right.

I need a more powerful exposure unit.

[blue moon]

I think he is talking about the unexposed emulsion, I also use a needle to get that out on rougher screens. Will definitely try the spot gun when I get a chance (about once a quarter).

To eliminate the scumming, just wipe/blot the screens after washing them, before letting them dry. It is safe to wipe the squeegee side, but the shirt side has to be blotted. We started having the scumming problems about a year ago and this took care of it. Now it is just a part of the process . . . (yes it is a fix for some other issue, but no time to tackle it now).

pierre

[mk162]

Ours is backwards, it's not safe to rub the squeegee side, the shirt side is fine.

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.

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%

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).

[bimmridder]

Sounds like we might need a new thread on correct exposure. If so many are dealing with  emulsion scum, there is at least one problem you should consider correcting. 

[mk162]

That's as dialed in as she gets, any more and it breaks down, any less and it washes off.  That is the best I can get with the setup I have now.  Proper rinsing helps tremendously.

[alan802]

Ours is backwards, it's not safe to rub the squeegee side, the shirt side is fine.

Why is that?  Are you finishing your coating procedure with a final stroke on the squeegee side of the screen?

[Shawn (EIP)]

You ever get the screens all set up and registered then you notice a small dot in a letter. Its not coming clean with press wash, screen opener, emultion remover or anything. Its just a little dot of emultion or something. I get one maybe 2 to 3 times a year. Instead of burning a new screen grab your spot clean gun. It will clean it out in no time and I have never hurt a screen. Just saved me this last week on a rush job that had 3 or 4 spots.

I do the same, works awesome.

[mk162]

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.

[alan802]

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.

[mk162]

Nuarc 40-1K

I want at least a 3K light for my next unit.