Jaggedness in stencil

[nismoasfuh]

Ok, I'm getting pretty bad results all of a sudden. My stencils are coming out jagged on straight lines and corners. Don't have a picture but I'll try uploading one tomm. I never had the problem before with any of my screens and now it seems like they all slowly but surely started doing it. I told my co workers it can be anything from screen tension, not a black enough positive and or just a old and abused screen (tension). My positives are as black as they can be so I don't think it's that. And the most upsetting thing is that when I brought up my situation everyone kind of shrugged it off. They even told me that I might not be using the right mesh count. But I really really reaaaaally doubt the difference between  a 110 to a 130 screen make that happen. I definitely can see jaggedness and it honestly makes the prints look really bad and not sharp.  I made my boss buy a tension meter from ebay for 80 bucks and in the process of convincing him for atleast a few Marukami 110-s'  I hope that the tension meter does its job and proves that all the screens I have been using have very low tension as I presume. Is there any other ideas as to what might cause this jaggedness. My positives are really black, I was the screens well and finish with a degreaser as well. I'm just hoping a new screen will eliminate this issue
Thanks in advance!

[Binkspot]

Bad coating, not bridging the gaps or under exposure.

[jvanick]

Yup.. what Brian said....

do you guys have a Stouffer strip or exposure calculator of some sort?

[Frog]

I guess, EOM emulsion over mesh, something that I had never heard of the first twenty years of my screen printing.
This article really opened my eyes, and we are lucky enough that the author shared it here.
http://www.theshirtboard.com/index.php/topic,2621.0.html

[screenxpress]

What if the film output is at too low of lpi where the missing dots cause the jaggies on 110/130? 

Just a thought.

[Underbase37]

Bad coating, not bridging the gaps or under exposure.

This^^

Low tension screens can still expose with sharp edges. This sounds most likely to be an EOM issue.

Murphy37

[Dottonedan]

Also, with under exposure,  even though your EOM might be good, you could be washing off your needed layers of emulsion, causing the mesh threads to show more on your line work. It's the same thing these guys are am saying, but adding the wash off idea.

[nismoasfuh]

Thank you your answers are great! That  article is a gem as well. definitely will be looking into tackling all this, thank you guys again. This information is priceless to me. Just a quick thought however, last I stepped in the dark room it was really hot. And we don't have a dehumidifier. I'm in Miami and it is summer...haha

[Underbase37]

Get a dehumidifier.

 http://www.kiwo.com/s/Importance-of-maintaining-a-low-humidity-environment-in-screen-making-2-column.pdf

Murphy37