Mesh
Make sure your fabric is squarely in the clamps or locking device. A quick way to square the mesh to the screen is to use the manufactured edge of the fabric as your guide in your first clamp or channel hold down on one side of the screen.
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The edge of a roll of mesh is called "selvage". This area often contains manufacturer's mesh type and thread diameter information. It can be used as a straight edge to align your screen inorder to maintain mesh squareness relative to frame.
It is also possible to draw a very precise line in the direction of the warp thread to align to as well. Line up the selvage or drawn straight line to the clamps, secure, and square up frame to clamps. |
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Make sure the fabric is softened properly in each corner of the screen to avoid excessive corner stress when applying tension. A quick guideline for softening corners; make sure you can pinch the mesh with all fingers in one hand. This should be adequate softening for large format screens. (The amount of softening depends on screen size, large format needs more than textile screens.) |
Note: To avoid mesh slipping when tensioning, make sure your clamps and or channels are locked, replace locking strip and or clamp rubber when worn or where excessive glue may have accumulated.
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Tension Meters are directional. When placing a tension meter on a measuring point as shown at the left make sure it is square to the frame. It will measure the tension along the longest part of the base of the tension meter. Two measurements are needed for each point shown with a red dot. One for the length of the screen and one for the width of the screen.
- Always calibrate your meter before use. Place on the glass plate that came with kit. Adjust outer ring so arrow points to "zero".
- Avoid dropping meter, always place back in case when not in use.
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Make sure both directions (warp and weft) are brought up evenly in tension, use psi pressure or the amount a newman roller turns or a draw bar frame moves to avoid breakage. Check tension levels in both directions during the stretching process (use newton meter) to be sure the tenison measurements are within 1-2 newtons in both measuring directions as you continue stretching to your targeted tension level. The center of the screen is most commonly used for intitial readings. As the tension approaches 80% of of the 'standard' tension listed below check all four corners in both warp and weft direction to make sure the tension is not above the center tension. Soften them if necessary to avoid over tensioning of the mesh near the corners which is where most rips begin to occur.
Use manufacturers guide for each mesh count.
Note: using the same tension level on different mesh counts is not recommended. Thinner thread diameters will not reach the higher tension levels of lower mesh counts, ie: a 110 mesh vs. a 300 mesh. The 110 is stretched to 27n/cm (mid-range) compared to 22n/cm for the 300 mesh.
Try to use the middle range of the recommended manufacturer’s tension guide. Smartmesh has excellent registration properties even when not stretched to the maximum tension. A middle range tension will give excellent print results while keeping the mesh below critical breaking points present in maximum tensioning.
Check you Equipment: If you have difficulty achieving tension level, check the stretching equipment air tubes for holes or too much water in the air lines or; do you have enough air pressure in the air line supplying the equipment to achieve enough force in the air cylinders to pull the fabric to tension? If necessary, place a filter on your air regulator system to eliminate water from the line. Also check to make sure cylinders are properly working forward and back when applying air.
Check tension levels: in the following areas of the screen. middle of the screen, check warp and weft, all 4 corners - 10" from inside of screen on large format 60"x120" or four inches in on a tectile frame, also measure the middle of each frame side. Tension levels should be balanced and within 1-2 newtons of center tension (target tension) level.
Recommended: 3 stage tensioning for screens over 50" outside diameter. Also works well on critical textile screens with higher mesh count for process, sim process, or index printing.
Example: (Check guide for recommended tension levels for the mesh count you wish to stretch.)
- 1st tension - 15 newtons, release tension to 0,
- 2nd tension - 18 newtons, release tension to 0,
- 3rd and final, 21 newtons.
Multiple tensionings help the mesh stretch and relax.
- This will help the mesh achieve stability and have a higher retained tension on stretch and glue screens than with a single stretching followed by adhering to frame.
- This method also works well on stretch and glue textile screens in the higher mesh counts to achieve a higher cut out tension and post print tension.
- Higher retained tension can also be obtained by allowing the mesh to sit at 3rd stage tension levels for five minutes and then bringing the tension level back up to recommended tension.
- Staging helps the mesh stretch and hold tension so that the final tension will maintain targeted levels better.
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