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screen printing => Screen Making => Topic started by: spotcolorsupply on May 06, 2012, 11:10:06 PM
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We recently had an issue with our restretches... Hate to admit it, but a good customer of ours called one day saying that the screens he just received were only 14 newton’s... :o
We typically stretch a 155 to 30 newton’s; at least I thought we did...??
I always knew our tension meter needed calibration, but I think our guy may have dropped it. The customer that had the issue tested our screens every time he got a batch and was very happy. He claimed around 27 newton’s on a 155..??
So it takes 7 - 10 business days to get our meter calibrated... ???
That won’t work, we have 200 screens to do, and we are getting backed up. :-[
So we bought a new one shipped in NDA... Gonna get the old one calibrated for a backup. ;)
I go to test the new meter and I can’t hit 30 newton’s without popping the screen??
Now I think both of our meters are out of whack (Our old one, and the customers)??
Maybe he is expecting something that isn’t possible on the first stretch??
I pondered this conundrum over the weekend, and came up with a solution ;D
I modified our stretcher (M&R Max Newton)...
Can’t say what I did :P, but it involved a grinder, A file, A chop saw, and some other stuff... ;D
At the end of it I can hit 40+ newton’s on a 155... (On the first stretch, with a calibrated meter)
My question is...
How high should we go?
Using 155 standard mesh as an example...
I don’t want frames popping on UPS.
I was thinking 30 newton’s...?
A lil less for higher mesh, same for 110s...
What yall think?
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I was just glad your 'fix' did not require stuffed dolls and chickens. :D
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I was just glad your 'fix' did not require stuffed dolls and chickens. :D
Who says it didn’t... That is why I made the list so short...
I can’t give up all of my secrets :P
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LOL.
I'm not a real good source for your question and I'm sure many will weigh in tomorrow.
I can get my 160 mesh Newmans up to 30 and am comfortable with that...for the mesh I'm using.
I would "think", if you can ship out statics at 30 newtons and the customer were to test at 27, he "should" be ecstatic. I know I would have been. My statics were more in the 14-17 range. Only found that out after I got a meter.
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I'd take them up to 30-35 and hope they make it through UPS shipping. I think anyone using statics would be very happy if their screens work hardened around 22-28 newtons.
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i agree with Alan..anything mid 20's for statics is a great place to be work harded at...
I would also do some testing at how well they "travel" through the shipping systems....just to see what will and will not make it
sam
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We recently had an issue with our restretches... Hate to admit it, but a good customer of ours called one day saying that the screens he just received were only 14 newton’s... :o
Had a same issue 2 weeks ago. Returned all screens to the manufacturer.
I would be happy is I could have them in low 20's. I do not do much of advanced stuff, but printing part is much easier with a nice screens.
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Brannon, borrow mine dude.
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IMHO, work hardened at anywhere over twenty N/cm for a single stretch is excellent. I have more than a couple frames I stage tensioned on a mechanical stretcher up to 45N, they work hardened just over twenty. Hopefully it's easier with a sweet pneumatic rig like you have. :)
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IMHO, work hardened at anywhere over twenty N/cm for a single stretch is excellent. I have more than a couple frames I stage tensioned on a mechanical stretcher up to 45N, they work hardened just over twenty. Hopefully it's easier with a sweet pneumatic rig like you have. :)
I agree I am never impressed with screen tension out of the box what it work hardens at is the key. Stage tensioning is really the only way you will ever get a 20+ work hardened static other wise they will end up in low teens or worse. I have proven this so many times over the years trying all the major screen vendors, as of yet the only decent statics I can get are through a local guy that goes above and beyond for our screens.
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So next question...
Would it be better if all mesh counts were stretched to the same tension?
I can obviously pull a 110 - 155 to a much higher tension than I can a 255 - 305...
So would the screens actually print better at a slightly lower, but more similar tension level from 110 to 305...?? :o
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i think you should stretch them high as possible without them busting, they will lose tension. Everybody will tell u something different. I know for a fact that as long as you are printing say 305 mesh, all with similar tension, you can get great results. I did some beta testing for a software seperation company years ago who gave me a large list of things I had to do to be a beta tester. there major request was high newton roller frames. Guess what, I printed their 8 color sim process job on 305s with 14 newtons and sent them the sample. They called and said it looked better than any they had ever seen, how did I do it? NOt saying I want mine at 14 newtons, just sayin it will work. (dont get it twisted homie! mine better be tight.)
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I would check with the mesh manufacturer. They will be able to tell you the ideal tensions for each different mesh
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I would check with the mesh manufacturer. They will be able to tell you the ideal tensions for each different mesh
That is actually what my rep suggested... Similar instead of maxed out...
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there is a different recommended tension for 110's vs 305's vs 230's and so on. They should have a chart of what they recommend.
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I'd take each mesh count up to the manufacturers max recommended level, and they'll drop significantly from there depending on mesh brand. I have 4 different manufacturers mesh that I've been stretching lately and it's really cool to see which ones lose the most tension after the first stretch and which one's actually are "low elongation" like they claim. I stretched a few 305's the other day and brought them up to 30 newtons and came back an hour later and tightened the corner bolts and set it off to the side so it would relax a bit, and I was very surprised that a few hours later it had only lost about 2 newtons in tension. That's a low elongation mesh, and it wasn't one of the major manufacturer's mesh either, which was why I was as surprised as I was.
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An hour is a pretty goodly amount of time to 'relax' though--I've tried 3-stage tensioning, and just kept some by the stretching table for weeks, retensioning 8-12 times (Trying to simulate a fancy stretcher long term ;D ) and they all lose tension on that first run--less for those paid more attention to, but some nonetheless.
Seems like you can tell how 'low elongation' mesh is by much tension does it lose on it's first print run... all other things the same.