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screen tension....higher NEED help

Posted on Wed, 20 Sep 2006 at 16:50



I have just read an article that made me see my screen tensions are no where near where they should be I'm trying to get20 to 25 N\cm but I'm
losing tension after mesh is adhered to frame. I am consistantly losing any where from 7 to 4 N/cm.....any input would be appreciated.

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tbone says: Hi Lance, There are a few things that could be causing you to loose too much tension. Here are some things to look into first. 1. Your frame profile might not be stong enough for your ...

Hi Lance,

There are a few things that could be causing you to loose too much tension. Here are some things to look into first.

1. Your frame profile might not be stong enough for your tension requirements. What are the size of your frames and the dimensions of the beams? The larger you go in frame size the bigger the beams need to be to stop deflecting and loosing tension.

2. What are you using to stretch the frames with? If you are using a larger roller frame to stretch screens with, you will loose more tension than you would with an air clamp system. The reason that this is, is because the air clamps pre- stress / pre-bow the frame inward when stretching the frame, and when the frame is released frame the air clamps, it wants to push it's self back out to it's original size and shape. This counter acts any loss in tension that might occur after the frame is released. The roller frame will not do this and the center of the frame will deflect inward, and give you more tension loss and inconsistent tension on the mesh from the center to the corners. You can counter act this by doubling the amount of reverse curve you put on the roller frame when you load the mesh.

3. What mesh brand are you using? No I am not trying to be a sales man here. Not all mesh brands are created equal. Find out what the percentage of elongation is with the mesh you are using. I have seen a spread from 3% to 15% from different manufacturers, or even from one mesh count to the next from the same manufacturer. If you cant get the tension to the level that you want after cut out, it might be a good idea to stretch the mesh from 3% to 15% higher to begin with, so you will end up with the tension that you want after the mesh has relaxed and stabilized

Just some things to think about. I hope this helps.

Best regards, Peter Duff.

posted on: Fri, 09/22/2006 - 12:14am
Lance says: thanks for the input...never thought about the beams size making a dif. But that's VERY likely....my screens are only an inch. So my next order I'll go 2 and see if that gets me there. I use an accu strech ...

thanks for the input...never thought about the beams size making a dif.
But that's VERY likely....my screens are only an inch. So my next order
I'll go 2 and see if that gets me there.

I use an accu strech machine to strch with. I have been told by them and my mesh supplier that I should be able to get as high as 30 If I want
to go that far.

Asfor my mesh supplier It's Saati Print I've use them for 12 years never
really had a prob. with the mesh. I really believe it's more in my process.

again thanks for the input...and I will look into what you've said.

posted on: Tue, 09/26/2006 - 8:25pm
anthony-whalen says: One thing that can cause the loss of tension in your mesh is relaxation of the mesh itself. When a mesh is initially stretched the molicules of nylon will straighten out over about 15 minutes and will ...

One thing that can cause the loss of tension in your mesh is relaxation of the mesh itself. When a mesh is initially stretched the molicules of nylon will straighten out over about 15 minutes and will drop some newtons. Don't glue your mesh to the frame right away, wait 15 minutes, test tension again, and tighten back to target tension. If you want to, retension one more time. I would go a little high on the tension to compensate for the loosening that will happen after you glue the mesh to the frame. If your frames are strong as they should be, like TBONE pointed out, your frames should hold tension much longer. A little extra time to do things right is all it takes.

posted on: Sat, 12/09/2006 - 7:45pm

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