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screen printing => Screen Making => Topic started by: ffokazak on May 04, 2016, 06:24:11 PM
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Just thought I would share an experiment I am working on with you guys and see if anyone has any experience with it!
So after the initial tensioning of some mesh today, (230 Saati @ 25 N ) I started to essentially do CPR motions on the mesh to see if I could knock down the tension a bit. Basically trying to stretch the mesh prior to the first run. As a guitar player for a few decades, when putting new strings on I will stretch them out so they stay in tune right off the bat.
After easing around the screen pushing the mesh downwards and sometimes all the way to the stretching table for a few minutes, the tension had gone down to about 20N.
I tried the same process after bringing it back up to 25 N and the result was nowhere near as dramatic. Down to 24 N.
Has anyone tried anything similar? I guess I am curious to see what can be done to expedite the work hardening process. I have been wondering how shops will bring newly stretched screens into production.
I have the screens labeled and will document them for simulated process prints, registration issues, or any dreaded moire down the road.
Interested to hear how/if you guys do anything similar!
Cheers!
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Back in the day we would bring a screen up to tension and put a 5 gallon bucket of ink on it for a couple of hours. Retension and repeat. Took forever to get a screen done. I finally would stretch a screen around 15 ncm or so over and put it into rotation. The press would work harden the screen to the ncm range I wanted.
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my procedure that seems to be working pretty well:
for a 24N max tension (thin-thread) screen:
bring up to 15 or 16N and let settle 20min or so
release
bring up to 20N and let settle 20min or so
release
bring up to 24N and lock screen
take to rinse out and spray it out (we LIGHTLY mesh abrade at this point, but I won't get into that here)
let dry over night
put on stretcher and bring back up to 24N
over the next few cycles through the shop, the tension will drop to around 18-20N.
after 4 or 5 cycles, bring back up to 24N where it will stay for quite some time.
something I noticed in the last 6 months is that work hardening was taking us longer after we got our printing technique down. Now that we print with minimal off contact and minimal squeegee pressure, the screen isn't getting as pulled or worked as it was before.
Sonny: 15N really???? What's the point of retensionable screens if you're printing with a floppy sloppy 15N ?
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I read that as 15 over the target tension, then it would settle.
I read an article some many years back about hitting a freshly stretched screen with a very high pressure pressure washer - about 5k - This releases the stored tension in the knuckles of the mesh as if you were pulling a squeegee over the fabric multiple times - MASSAGING- the tension out of the knuckles. After hitting it with the pressure washer they would go back and tension it up again.
If you are printing with much lighter pressure now jvanick, you are "lightly" massaging the knuckles, which is why you are seeing tension readings drop slower.
You need to get back to shiatsu massages ;)
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Colin -- you're right... he did say 15N or so OVER... not enough coffee before i started responding.
And yes 'spray' out is with our pressure washer... seems to help a lot.
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for as much of a screen junkie that i am..
i just make the screen and put it into production. no fancy tensioning trick with on/off up/down wait a min .. just wack it, lock it clean it coat it shoot it tape it print it.
Here are my tricks.. 10 mins from frame to tape with bolt mesh.
https://youtu.be/YMcKjQAr988
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yes, adding weight uniformly, or even just waiting, let the stretcher keep stretching, walk away and take care of something else. By the way, I've changed a billion sets of strings over the last 50 years, and never stretch them, you will make the string weaker at the anchor points, which will lead to intonation problems and or breakage. Or not, if it's been working for you though. This has never caused me problems with steel strings, nylon do indeed take a day or two to settle. Sufficient windings are the real deal, or locking tuners if you need them...
Steve
Damn, now I wish I was home playing...
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I read that as 15 over the target tension, then it would settle.
I read an article some many years back about hitting a freshly stretched screen with a very high pressure pressure washer - about 5k - This releases the stored tension in the knuckles of the mesh as if you were pulling a squeegee over the fabric multiple times - MASSAGING- the tension out of the knuckles. After hitting it with the pressure washer they would go back and tension it up again.
If you are printing with much lighter pressure now jvanick, you are "lightly" massaging the knuckles, which is why you are seeing tension readings drop slower.
You need to get back to shiatsu massages ;)
I don't have the ying yangs to stretch smesh 15 newtons over
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for as much of a screen junkie that i am..
i just make the screen and put it into production. no fancy tensioning trick with on/off up/down wait a min .. just wack it, lock it clean it coat it shoot it tape it print it.
Here are my tricks.. 10 mins from frame to tape with bolt mesh.
https://youtu.be/YMcKjQAr988
This is how I did it for years.
Now I make a 10 min. phone call and I have 40 prestretch screens delivered to me ready to go ^-^
Murphy
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^^That's cheating. ;)
There was a good paper from the SPTF on rapid tensioning back in the day that used a similar technique, but on the rollers as you stretched.
Doesn't seem to help much IME.
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for as much of a screen junkie that i am..
i just make the screen and put it into production. no fancy tensioning trick with on/off up/down wait a min .. just wack it, lock it clean it coat it shoot it tape it print it.
Here are my tricks.. 10 mins from frame to tape with bolt mesh.
https://youtu.be/YMcKjQAr988
John,Why the bolt mesh, cost?
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that shop was all cost driven. never retensioned and treated the screens like crap. id show up every couple weeks and restrech a dozen with cheap economy bolt mesh.
wacked it to 40 and it would settle down to 25 after a couple runs.
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that shop was all cost driven. never retensioned and treated the screens like crap. id show up every couple weeks and restrech a dozen with cheap economy bolt mesh.
wacked it to 40 and it would settle down to 25 after a couple runs.
I'm a little nervous about re-tensioning murikami S mesh, it's already so finicky. The S mesh statics that we have seem to never loose tension, only a couple newtons. But maybe they push it a little more during the stretch. All our newmans are meshed with shurlocs. Once we went to shurlocs, I stopped trying to retention because they seemed to always pop.
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I stretch and retension 280 s mesh. I always stop at 24n with the rollermaster whether new or retension because they reach their max of 28 by the time I tighten the rollers.
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I stretch and retension 280 s mesh. I always stop at 24n with the rollermaster whether new or retension because they reach their max of 28 by the time I tighten the rollers.
Will give that a try. I think I need to buy a second tension meter too. Just to make sure our's isn't off. It "seems" to be on point as far as I was instructed by stretch devices to check, but I guess you never really know without a comparison