Fresh cup of coffee so the brain is starting to tingle. Let's see if I can get this into words.
Without a doubt your problems are due to the mesh not being loaded square and improper corner softening. This places different loads across the mesh and what may be 22n here is 30n there causing a failure.
first thing is to stage your roller tubes, see those hash marks on the corners, those are your guide marks for where to roll to later in the process. Once you get to know your mesh and how it rolls, where you stage the tubes will depend on mesh counts. low mesh will stage at 5 or 6 as it won't roll much vs high mesh will roll father and need to be staged at 1 or 2.
Stage the tubes so the top of the locking channel is at the 3rd hash from the inside, do this for all 4 tubes, looks like this.
Preparing the mesh panel. It's best to work with a 2-3" of mesh overhang. A 60" bolt will yield two panels at 29" x 37" we don't cut the mesh with scissors, nick the edge and rip the mesh by hand. this ensures you get a straight 'cut' as the tear will follow a single thread. THIS IS VERY IMPORTANT to getting a clean edge.
measure down 37" and rip it from the bolt. You'll need to trim the manufactured heat knife edge, fold the mesh in half, trim 1" from the edges, rip em off then rip at the center and you have 2 panels 29 x 37
lay this panel over the frame and square it up best you can.
Inserting the Alignment clips.
We have to be careful and compress the clips and not drag them or let them nick the mesh while we prepare the channel for loading the locking strip. long tubes require 3 clips, short tube 2 clips. Insert clip 1 about 2ish inches from the tube end , then holding that clip, with your other hand pull gently on the mesh at the other end making sure you have an even amount of overhang and insert a clip at roller end. Place clip #3 in the center.
Now we have to measure the distance from the edge of the mesh to the clip in the channel. using your locking strip, place the pointy end at the edge of the clip and lightly pulling on the mesh edge, use your thumbnail to mark the location on the strip where the mesh edge lands
Keeping your thumbnail on the strip do this for the middle clip. go back to the first, remeasure, back to #2 then onto #3.. repeat until all 3 clips are EXACTLY THE SAME.. this is your foundation for a square panel so GET IT RIGHT!
Insert your locking strip until it hits the first clip, remove the clip and move to #2 then onto #3. Double check the measure distance and if needed, go back to the clip step, re-measure and re-insert the locking strip.
move to the other long roller and repeat the clip inserting steps starting with the #2 clip in the center. Before you place clip 1 and 3, check the short tube ends for mesh overhang, make sure it's even as this is where people get a crooked panel. We don't want the panel to tight in the frame at this point so wiggle #2 and leave just a little bit of slack across the panel so the locking strip is easy to insert, insert clips 1 and 3 then measure the same as above. Before inserting the locking strip, check short tube overhang so it's even. If you have to force the strip into the channel, back off #2 a little and repeat measure. Once the strip is inserted, double check the overhang on the short tubes and adjust by pulling on the mesh at the short ends to get them even.
Move to short tube end, should be square, place the clips, measure and insert locking strip.
move to last short tube, clip, measure, strip and you're done.
CORNER SOFTENING
The 2nd reason most frames pop is the corners didn't get softened enough. this is a reference to where the softness should be, the red line is a failure zone. If the corner is pulled beyond that zone, it'll pop. Keep it within the black and red and you're good. I like to keep my corners really tight, helps with coating, CTS machines and that buzzy flap in reclaim.
Measure your corner softener tool to same size as the diagonal of the corner of the frame. use that to measure in from the corner, place a clip there, do the same on the other side. using a sharpie, run it along the channel edge to the clip. now soften the corner down to the table surface. You'll see the marker line angle down from the clip and not any farther. repeat on each corner.
ROLLING THE TUBES
This is where those hash marks come into play again and where my techniques differ from others. At this point i don't need a meter and can simply use the hash marks as a reference of where to turn the rollers. We staged the rollers at the top of the channel, now we roll the tubes to the bottom of the channel and align it's edge with the hash marks.
For the initial tension with S-mesh i move all rollers to hash mark #2 and lock the bolts. Trim all excess mesh and tape em up. Conventional mesh or other brands will go to hash 3 or 4 depending on tension range.
This results in a tension from 22 to 28 and is ready for production. No relaxation needed, simply degrease and put into production. Same goes for conventional mesh, i wack it and lock it and send to production. I have not let mesh relax during initial tension in years now and have the exact same results as staged tension with half the time and effort.
When it comes back, roll 1 short tube 1 hash and back into production.
2nd time around, long tube 1 hash and this should keep the frame good for some time. Double check tension and if needed move another hash.
FINAL THOUGHTS
I've been stretching roller frames since 1991 and have stretched 10's of thousands of frames both manually and with a roller master table. I've used every mesh brand including cheap china filtration mesh to 60 newton high tension mesh printing 85 line tonal work at 800+ impressions per hour. I've seen it all and tried every technique including skewed loading to create a diamond shape opening. the magic number for tension is 25 newtons as that is the minimum force required to offset the deflection forces of the flood bar filling the stencil, that is what tension is all about, creating a printing plate for the flood and a spring board for the squeegee. keep em all around that range and things just work. Go up to 30 and it's good.. 40 is the next sweet spot and after that is 60.
There you go, hope that helped. Feel free to call me if you need some hands on training and or want to fly me out for training.
