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screen printing => Screen Making => Topic started by: mimosatexas on August 31, 2014, 06:01:59 PM
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I am about to build my screen storage room, which will house my coated screens, films, a coating station, and have a FPU. This room will be inside another larger room, which will have my washout booth, a dip tank for post exposure, and my exposure unit, and a few other screen specific items.
I have the humidity question handled, but now I need to figure out how to control the temperature of the screen storage room. I was thinking of putting a small window unit A/C in the wall of the smaller room, but that would mean hot air would exhaust into the larger room which seems like a bad idea. I am also worried about heat during the winter, but I do have a small ceramic heater that I could toss in that room when needed. The walls and ceiling will be well insulated and the door will have a tight seal.
Mostly just wondering how others control temperature specifically in their screen storage.
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Find a small hot split unit used. Air and Heat.
Usually not crazy expensive if you can find them used.
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Our screen "room" is 65 sqft, the back is insulated because it backs up to an exterior block wall. One dehumidifier will keep it in the 90's in the summer, 70's in the winter. To boost the temp in the winter I have a small milk house heater that will keep the room in the 90's.
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I think Gtmfg I'd referring to a mini split, that was going to be my suggestion.
You can get heat pump versions of them for about $800 bucks new.
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You can get the portable AC/Heat units with 14k BTU's for around 500 bucks from amazon.
I'm using one of those and it keeps the room in the mid 80s' in the summer. Not used it in winter yet so we'll see how that goes.
If you want to spend over a grand, the mini split units with heatpump are perfect for a screen room, if you have the ability to put the pump outside even better as that way you only need a 3" hole in the wall for the plumbing.
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Thanks! I'll start looking into the mini splits.
For the time being, are there any downsides to using a small (like 5000btu or less) window unit to keep the temp down? Any issues with having it completely inside (cool air in the screen room, heat venting into the larger room) besides the extra heat?
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You got it!
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We have a 15x20 screen room and use a window unit, works great for us. And now that our entire production area is climate controlled, it won't have to run as much
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We have a 15x20 screen room and use a window unit, works great for us. And now that our entire production area is climate controlled, it won't have to run as much
And no issues having it inside? I'm finding no info on whether its safe to have a window unit fully inside. I know the portable units tend to give off ozone which is why they say explicitly that they should be vented outside, but nothing on standard window units.
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Well maybe I'm confused. Our unit is in the wall and pulls air from outside. Sorry if I am talking out of the side of my neck
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unfortunately due to the layout of my shop, the A/C would have to go on an internal wall. I could rig up some kind of ducting I'm sure, but if the only downside is heat in the other part of the room, I would rather just deal with it to be honest.
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i wouldn't do that, you can either do a mini split system or a free standing unit that has exhaust hoses and vent it through the roof...a much better bet.
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After reading about the mini splits, I think I'm going to go that route. I guess you can get pretty fancy with the configuration and they are hugely more efficient which would save money in the long run. Thanks!
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Exactly, mini-splits are awesome. We might add one to the screen printing area if the Radicure is still dumping out too much heat.
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We are a new shop and I am also setting up my screen room. My screen guys says he is not concerned about the heat during the summer but is more concerned with it being too cold in the winter. I am planning on putting a small portable cooling unit in the exposure room that has a 3" exhaust duct through the wall but I am not planning on cooling the screen room at all. The screen room is a separate small room attached to the exposure room but is sealed. I will put a small heater in the screen room to keep the temperature up during the winter. I am more concerned about the humidity in the screen room. Am I missing something?
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I'm in central Texas and my shop is regularly around 110 degrees when printing/curing, and probably over 100 during the middle of the day regardless of what I do. My coated unexposed screens tend to fair fine in that environment for a few days, but I have noticed it is hard to wash out a stencil a few times on screens that have been stored more than 2 or 3 days this summer. This isn't a problem on spot jobs, but when trying to hold super fine detail/halftones, having to blast it out for a while isn't ideal. A small heater in the dead of winter if plenty here, but I need something beefy for right now to keep it cold.
Controlling humidity has been as simple as having a 40 pint dehumidifier that I empty when I leave for the night and when I get into the shop in the morning, though I am going to be adding a pump to automate that soon.
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Some notes on screen rooms:
1. If you add diazo to your emulsion try to keep the room at 80 or below. Over 80 degrees effects the diazo and 'dark hardens' it on a coated screen and in the bucket. This shows up as a screen where it is difficult to develop the image and usually there is some edge quality loss. Air conditioning helps, I'd like to know more about the split units or even a photo of one, I've never come across one and they sound like a good tool for screen rooms.
2. Yes it can be too cold in a screen room as well. Emulsion will get much more viscous in cold conditions. Coated screens can also get too dry. The winter cold weather drops humidity a ton and can make the room so dry emulsion will crack during the printing process. 35% humidity is a good balance. In winter you can run a small vaporizer to bring up humidity to 35%, Hot humid conditions may need a de-humidifier depending on the location of your shop.
3. Very hot humid rooms are tough to dry out. High temperatures make it harder for the dehumidifier to work, using air conditioning helps bring down temps to where the dehumidifier can pull more water out of the air.
4. 70-80 degrees at 35% is the target. Vapor barrier doors like those used in super markets help keep wet air out, dry air in.
5. A moisture meter is the easiest way to know if your climate controls are working. They aren't cheap, but a good moisture meter like we sell and use in our demos tells you exactly when the screen is dry to shoot. This tool helps make the screens predictable in terms of durability on press. Some screen rooms need to dry 20-XX screens to prepare for coating. This moisture in the screen room and it gets soaked up by coated screens. With a moisture meter you can measure the screen to see when it has re-dried and is able to shoot. Sure it will feel dry all the time, but the moisture it soaks up when wet screens are brought in can take 15-30 minutes to return to the dry reading on the moisture meter.