# Super tiny pin holes before exposure



## clznco (May 7, 2018)

So I’ve been dealing with having the tiniest pin holes in my screens pre exposure and I can not figure out why. I’ve decreased the absolute **** out of them so there’s no way it’s from them being still greasy- these are brand new screens btw. I bought a new emulsion and the same thing is happening. I typically coat 1/1 and was previously using wbp emulsion from ryonet. I mean these pin holes are so small - like the size of a mesh hole in a 200 mesh screen. 

Is it contamination in my screen room? It’s not humid, no air flow so not really much dust floating around. I figured even if dust was in the air it would just become a part of the emulsion and not instantly cause a pin hole. I’m stumped and have a ton of jobs to do so I really need to get this figured out!

Any help is appreciated!

Skyler


----------



## Luke T (Jan 21, 2010)

Bubbles in emulsion maybe? We fill our coater and leave it in the dark room for a few minutes to let all the air seep out and if necessary pop any remaining bubbles with a pin.


----------



## DNDL_MFG (Aug 6, 2018)

We had the same issues and we narrowed it down to two things, dust on the screen precoating (easy fix blow off with an air hose precoating), and there could also be dust in the exposure unit (like on the glass on either side). We just clean exposure unit regularly and blow screens off now. Hope this helps!


----------



## Kevin2coolair (Jan 9, 2017)

Try slowing down when you are actually pulling the scoop coater up the screen. You may be coating too quickly. And use plenty of angle on the coater. If you're scoop coater has a sharp and blunt side and you're using the "sharp" side of the coater, try switching the the blunt side for better coverage.
Also, dusty screens as mentioned already.


----------



## clznco (May 7, 2018)

This is pre exposure though so it’s not the exposure unit. And I coat them right when they’re dried so I’m not thinking dust. Even if dust did get on the screen while it’s wet with emulsion I’d think it’d become a part of the emulsion instead of being a pinhole you know what I mean? Not really any airflow in my dark room either


----------



## Jayz76 (Feb 8, 2018)

Good day

How many coats of emulsion are you applying, and when coating slow down the process slightly.


----------



## TABOB (Feb 13, 2018)

I've actually observed these forming with a loupe. If you coat the screen too fast and without applying enough pressure you will end up with some half filled mesh holes. As the emulsion dries, it does shrink quite a bit, and it pulls itself out of the half-filled holes. Improve your technique, or try doing two + one pass.


----------

