Dehumidifying

[ScreenPrinter123]

In particular for dc printing for those of u who use a dehumidifier that you don't always have on in a screen room/box, do you run your dehumidifier for like an hour right before taping your film to screen to suck out any remaining moisture in the emulsion or should this not matter if the emulsion was dried the day before with the dehumidifier?  I've heard it important to do on a video I once watched and while the guy has a massive operation I didn't get the impression he completely knew what he was talking about. I know peeps like Alan have a walk-in cooler for their screens so the humidity and temp are ALWAYS under control, but does it play a huge factor in exposing your screens properly for dc runs in particular if you don't have a dedicated room and only a DIY screen box with a dehumidifier and don't run it about an hour right before exposing?

Gracias.

[balloonguy]

I use a large cabinet with a dehumidifier like you are describing. I Always turn it on at least an hour before burning screens. I have nothing to to back this up but it seems like the emulsion and fabric would absorb moister out of the air. I know my shirts do. I feel like it is better to be safe.

[Colin]

We leave ours running 24/7.

We set the dehumidifier to 35% and let it run.  If there is nothing in the air to pull out, it doesn't kick on.

Lately it has been so cold that the humidity is below 30% and it will not kick on unless we have been reclaiming.  Even then it is only for a little while.

[Gilligan]

We leave ours running 24/7.

We set the dehumidifier to 35% and let it run.  If there is nothing in the air to pull out, it doesn't kick on.

Lately it has been so cold that the humidity is below 30% and it will not kick on unless we have been reclaiming.  Even then it is only for a little while.

Same problem here... But I like the heat... So I force mine on when we load the cabinet up.

[tonypep]

Our screen dept is really  seven connected rooms divided by dual swing restaurant doors. Deep inside the catacomb are the coating room, drying room, and coated storage rooom. Drying room has two ind. humidifiers which drain to the outside of the building. It can handle 8 screen racks on wheels and the humidifiers are only necessary during the drying process.

[ebscreen]

Unless you are storing your exposed and dried screens in a humid greenhouse or something I don't think it's an issue.
Having thoroughly dried screens is paramount with DC, but I don't think the small amount of moisture a dried screen
might absorb while awaiting use is of concern.

[Denis Kolar]

I run a humidifier in my basement because of my solvent printer.
With a heating season, my humidity goes down a lot. At least it did last few years.
This year I installed the humidifier and now it averages around 30%

Summer time is a different story, keep it around 40% with a humidifier running 4 hours ON and 4 hours OFF.