Author Topic: Screen Tension  (Read 4061 times)

Offline Maxie

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Screen Tension
« on: March 13, 2015, 02:16:14 AM »
I always measure my screen tension on clean screens.
I was wondering if it's possible to check screen tension with emulsion on the screen?
Will the emulsion have any effect the reading?
Maxie Garb.
T Max Designs.
Silk Screen Printers
www.tmax.co.il


Offline Screened Gear

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Re: Screen Tension
« Reply #1 on: March 13, 2015, 03:58:56 AM »
I always measure my screen tension on clean screens.
I was wondering if it's possible to check screen tension with emulsion on the screen?
Will the emulsion have any effect the reading?

You can measure the tension with emulsion on the screen. Now does it effect the readying, I am sure it does some but not enough to worry about. I have never measured the same screen with and without emulsion. I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

Offline mooseman

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Re: Screen Tension
« Reply #2 on: March 13, 2015, 09:14:37 AM »
I am sure you can get a reading on the meter when the screen is coated but think about this.

The meter reads the apparent tension in the structure of the mesh which has as its mechanical characteristics the weave of the mesh.

When the screen is coated the mesh is bonded to the emulsion bridging the open areas in the mesh and completely changing the characteristics of the mesh from an open weave to more of a rigid solid sheet so to speak.

Now think about placing your meter on the calibration glass, you will get a reading there also.
The difference being the glass is the ultimate solid, with virtually zero flexibility and ideally perfectly flat.

When you coat the mesh you are actually converting it to a solid sheet  for the most part which will report to the meter a surface the begins to look (to the meter) more like the glass than the flexible mesh. you will get a number most likely a number greater than zero but most likely less than you would get on the previously uncoated screen.
the test however is quite simple...test the same screen uncoated then after you coat it.
mooseman









« Last Edit: March 13, 2015, 09:24:28 AM by mooseman »
DUE TO CIRCUMSTANCES COMPLETELY WITHIN MY CONTROL YOU SHOULD GET YOUR OWN TEE SHIRT AND A SHARPIE MARKER BY NOON TOMORROW OR SIMPLY CALL SOMEONE WHO GIVES A SHIRT.

Offline jsheridan

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Re: Screen Tension
« Reply #3 on: March 13, 2015, 12:14:29 PM »
Simple answer, yes you can.

Better answer, you checked the tension prior to coating and you wrote that number in the corner of the screen so you can see it.






I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

HAHA... funny   :o



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Offline Screened Gear

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Re: Screen Tension
« Reply #4 on: March 13, 2015, 12:40:14 PM »
Simple answer, yes you can.

Better answer, you checked the tension prior to coating and you wrote that number in the corner of the screen so you can see it.






I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

HAHA... funny   :o

John you tension whore. You know you can push on a screen and tell if its 30n or 20n. Don't make tension out to be more than it is. Its just printing a shirt.

Offline Admiral

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Re: Screen Tension
« Reply #5 on: March 13, 2015, 12:42:28 PM »
Simple answer, yes you can.

Better answer, you checked the tension prior to coating and you wrote that number in the corner of the screen so you can see it.






I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

HAHA... funny   :o

John you tension whore. You know you can push on a screen and tell if its 30n or 20n. Don't make tension out to be more than it is. Its just printing a shirt.

Some people like to treat this as a science and use a meter to know when it's in spec or not.  Removing variables from screen printing is glorious.  There are enough headaches already.

Offline Screened Gear

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Re: Screen Tension
« Reply #6 on: March 13, 2015, 12:54:09 PM »
Ok just to put this to bed. I went and took a 80 mesh screen with a ton of emulsion on it, sorry didn't measure the EOM.  I measured it at 17n with the emulsion on it. Then I washed off the emulsion. It then read 16.5n in the same area.




Offline jsheridan

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Re: Screen Tension
« Reply #7 on: March 13, 2015, 12:55:15 PM »
Simple answer, yes you can.

Better answer, you checked the tension prior to coating and you wrote that number in the corner of the screen so you can see it.






I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

HAHA... funny   :o

John you tension whore. You know you can push on a screen and tell if its 30n or 20n. Don't make tension out to be more than it is. Its just printing a shirt.

I grabbed the wooden 110 screen, with a finger reading of 23n coated 1x1 and got a one hit white yesterday, it was awesome!
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Offline Screened Gear

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Re: Screen Tension
« Reply #8 on: March 13, 2015, 01:04:42 PM »
Simple answer, yes you can.

Better answer, you checked the tension prior to coating and you wrote that number in the corner of the screen so you can see it.






I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

HAHA... funny   :o

John you tension whore. You know you can push on a screen and tell if its 30n or 20n. Don't make tension out to be more than it is. Its just printing a shirt.

I grabbed the wooden 110 screen, with a finger reading of 23n coated 1x1 and got a one hit white yesterday, it was awesome!

Ok let me explain. I have tools here. I would guess more than most. I test everything, not as much as Alan but I know what my shop needs. All my screens that we use every day are in the 25n to 30n range. They hold tension great over their life time. I know from experience of "finger testing" them that they are still in our approved tensions. I am sorry that I was not more clear.
« Last Edit: March 13, 2015, 01:18:06 PM by Jon »

Offline 3Deep

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Re: Screen Tension
« Reply #9 on: March 13, 2015, 01:22:27 PM »
 ;D your tension screens are 35n his are 18n your still both make the same $5 dollars or getting ask can you go cheaper,  yeah I get it all this high tension top dollar equipment is mainly IMHO just to be like the Jones.  In the end only customers you'll have that are very strict on prints is corporate/brokers clients, then most of them are really trying to figure out how to screw you out of a few dollars :o  Just had to break the ice a little LOL
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Offline Screened Gear

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Re: Screen Tension
« Reply #10 on: March 13, 2015, 01:35:50 PM »
I am sure you can get a reading on the meter when the screen is coated but think about this.

The meter reads the apparent tension in the structure of the mesh which has as its mechanical characteristics the weave of the mesh.

When the screen is coated the mesh is bonded to the emulsion bridging the open areas in the mesh and completely changing the characteristics of the mesh from an open weave to more of a rigid solid sheet so to speak.

Now think about placing your meter on the calibration glass, you will get a reading there also.
The difference being the glass is the ultimate solid, with virtually zero flexibility and ideally perfectly flat.

When you coat the mesh you are actually converting it to a solid sheet  for the most part which will report to the meter a surface the begins to look (to the meter) more like the glass than the flexible mesh. you will get a number most likely a number greater than zero but most likely less than you would get on the previously uncoated screen.
the test however is quite simple...test the same screen uncoated then after you coat it.
mooseman

Mouseman,

The tension meter is not that smart. It only reads the distance from the base down to where the foot is. When the meter is on the glass the foot is exactly level with the base of the meter. When on a screen the foot will be lower, pushing the mesh lower then the base of the meter. The closer to level the foot and base are the higher the tension will read. It could be measuring any material. The emulsion on the screen will make the screen very slightly stiffer. So it does read a little higher tension. But even with my old 80 count screen with alot of emulsion on it it only read half a newton better. Good to know for the future.
« Last Edit: March 13, 2015, 01:38:58 PM by Jon »

Offline jsheridan

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Re: Screen Tension
« Reply #11 on: March 13, 2015, 01:39:47 PM »

 $5 dollars


5 bucks..  :o I sold that 1 hit white on a chinese made import raglan shirt for 19.50 a piece. I ran down to Walmart with the profits and bought me a Little Ceasers 5 buck pizza!

My screens are so awesome, I need to wear shades.

[/sarcasm]
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Offline 3Deep

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Re: Screen Tension
« Reply #12 on: March 13, 2015, 02:09:00 PM »

 $5 dollars


5 bucks..  :o I sold that 1 hit white on a chinese made import raglan shirt for 19.50 a piece. I ran down to Walmart with the profits and bought me a Little Ceasers 5 buck pizza!

My screens are so awesome, I need to wear shades.

[/sarcasm]
LOL you got it John
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Offline JBLUE

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Re: Screen Tension
« Reply #13 on: March 14, 2015, 01:04:30 AM »
Simple answer, yes you can.

Better answer, you checked the tension prior to coating and you wrote that number in the corner of the screen so you can see it.






I only check tension when buying screens. Once you have tested a few you can just feel the screen and know about where it is. Or at least know if its good enough to get the job done.

HAHA... funny   :o

John you tension whore. You know you can push on a screen and tell if its 30n or 20n. Don't make tension out to be more than it is. Its just printing a shirt.

I grabbed the wooden 110 screen, with a finger reading of 23n coated 1x1 and got a one hit white yesterday, it was awesome!

LOL... A 110 mesh screen. Are you making a box fan filter again?
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Offline ABuffington

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Re: Screen Tension
« Reply #14 on: March 16, 2015, 02:25:29 PM »
Tension Meters:  Once dropped they may need to be calibrated.  They read the direction in the long direction of the base.  So for both warp and weft they need to be parallel to the sides in both directions. 

John, love the sarcasm.  You forgot the mesh measuring tool, which is a quick drag of the thumbnail across the mesh to read the threads.  Hey I have done this at shops that don't mark screens, seems to work ok to get an exposure.

Al
Alan Buffington
Murakami Screen USA  - Technical Support and Sales
www.murakamiscreen.com