TSB

screen printing => Screen Making => Topic started by: 3Deep on April 04, 2018, 02:59:44 PM

Title: S mesh and Sticky screens
Post by: 3Deep on April 04, 2018, 02:59:44 PM
We bought some S mesh last year and love it, but here is a problem we are having...burn some screens this morning and notice that all my s mesh screens were kind of sticky and this screens have been in the dry room for at least 4 days or more ( baby powder fix) but my other screens just fine.  Can I assume that the s mesh screens are holding more emulsion? but still 4 to 5 days drying should be good.
Title: Re: S mesh and Sticky screens
Post by: Colin on April 04, 2018, 03:45:11 PM
Do you have a dehumidifier in there?  A tool to measure humidity?

Humidity may have gone up recently....

And yes, its safe to assume that ANY thin thread mesh will have more emulsion "by Volume/Weight/Per Square Inch" etc than normal thread diameter screens.

My bet is on the humidity being higher than it has been in the last few months.
Title: Re: S mesh and Sticky screens
Post by: ABuffington on April 04, 2018, 04:44:32 PM
Yes S mesh coats thicker.  Could make the print side very smooth and increase surface tension.  Try coating a bit less.  Humidity can also play a role.  Dehumidifiers really help year round consistency of exposure and properties.  Baby powder fixes all of this.  This is especially true of really long exposures with thick stencils or film. 
Title: Re: S mesh and Sticky screens
Post by: hoogie on April 05, 2018, 12:13:00 PM
Yes S mesh coats thicker.  Could make the print side very smooth and increase surface tension.  Try coating a bit less.  Humidity can also play a role.  Dehumidifiers really help year round consistency of exposure and properties.  Baby powder fixes all of this.  This is especially true of really long exposures with thick stencils or film.

Can you explain this baby powder fix?
First I've heard of this, pinholes? Any exposer problems? Thanks
Title: Re: S mesh and Sticky screens
Post by: 3Deep on April 05, 2018, 12:53:03 PM
Hoogie, before you tape your film to your screens if they feel sticky take a little baby powder and rub a little over the screen on the film side, then the film won't stick to the emulsion.
Title: Re: S mesh and Sticky screens
Post by: hoogie on April 05, 2018, 02:01:38 PM
Hoogie, before you tape your film to your screens if they feel sticky take a little baby powder and rub a little over the screen on the film side, then the film won't stick to the emulsion.

Interesting, first I've heard of this. I'll have to say something to my guy out there for this summer. We run two dehumidifiers and we still sometimes get sticking. Thanks
Title: Re: S mesh and Sticky screens
Post by: screenxpress on April 05, 2018, 08:12:51 PM
That tip has been posted  a number of times. 

An extremely light dusting (then spread around by hand) before taping the film down.

Film lifts off easy-peasy after exposure and I've never had a negative outcome (pinhole, etc) from doing so.

I pretty much do it even if the emulsion does not feel sticky.  Had too many times where some of the ink pulls off the film.  Does not affect the exposure, but makes the film not reusable.
Title: Re: S mesh and Sticky screens
Post by: mooseman on April 06, 2018, 08:29:37 AM
That tip has been posted  a number of times. 

An extremely light dusting (then spread around by hand) before taping the film down.

Film lifts off easy-peasy after exposure and I've never had a negative outcome (pinhole, etc) from doing so.

I pretty much do it even if the emulsion does not feel sticky.  Had too many times where some of the ink pulls off the film.  Does not affect the exposure, but makes the film not reusable.

Especially if you are using waterproof films, you absolutely need to powder. And if you do not pin holes are the typical result.
One comment on the powder talc based powder works WAY better than corn starch based  powder. If fact if you use corn starch based powder and your screens are holding more moisture content than they should you will see the corn starch based powder glob and grab the screen insted of evenly coating.
BTW talc based powder is the lower quality formula so it works for you all around.
mooseman
Title: Re: S mesh and Sticky screens
Post by: Sbrem on April 06, 2018, 04:44:25 PM
I can't believe I've missed the earlier postings about baby powder. We just got used to losing the films and making new ones. Now, I think I've read somewhere in the past 6 months or so about talc causing health problems? A recent discovery? Of course, it's been around forever in everyone's homes...

Steve
Title: Re: S mesh and Sticky screens
Post by: mooseman on April 06, 2018, 05:39:15 PM
I can't believe I've missed the earlier postings about baby powder. We just got used to losing the films and making new ones. Now, I think I've read somewhere in the past 6 months or so about talc causing health problems? A recent discovery? Of course, it's been around forever in everyone's homes...

Steve

Everything causes health problems. One day eggs are bad the next day they are good again, same with salt.
About the only thing that doesn't cause health problems is kicking the bucket.
I can't believe the amount of tee shirt fuzz that shows up in my shop and i am a puney manual printer. All that fiber and dye in your lungs has got to be bad. And what about those wonderful polyester fumes when a 50/50 tee makes the dryer run?
I quit listening to all that crap a long time ago the anxiety alone is enough to kill ya
mooseman
Title: Re: S mesh and Sticky screens
Post by: screenxpress on April 06, 2018, 06:37:28 PM
If you are not mining the talc power and breathing in the powders, it appears the biggest risk is to women using it in their reproductive areas.

So....I imagine as long as you are using your 'fingers' to spread it around and nothing else......you'll probably be ok  ;)