What`s wrong with my mesh

[Rockers]

I have an issue with a virgin Roller Frame. Just stretched it a few days ago and was in the middle of doing some test prints noticing this strange pattern on the print and in the mesh. What might be the cause for this? I hope I don`t have to restretch that frame. Oh by the way the mesh count is N166.

[broadway]

The picture looks like a moire pattern. But it looks like you printed a solid image area with out a dot pattern. Did this pattern happen right away or did it get worse as time went on? What material are you printing on? Last week i printed on french terry sweats and  the french terry weave under the garment showed up in my print. I ended up pfp to get rid of the pattern. Try to take a better picture.
Peter

[Shawn (EIP)]

It could also be the film wasn't opake enough and left behind some exposed emulsion in the print area, it's happened to me.

[Frog]

A moire interference pattern requires two grids or sets of dots to "interfere" with each other. This is usually two sets of dots printed at the wrong angle in relationship with each other, or dots interacting with the "pattern" of the mesh itself, hence our angles and dot frequency suggestions.

I can't tell if this area is wide open or half-toned.

[inkman996]

I have seen this before in stretched screens and it does effect the print. What I think it is tho not even remotely positive is that the mesh when stretched is askew more so in one area than the other hence the strange effect in the weave. I also wonder if the mesh itself has a defect in the manufacturing, kind of like some of the threads are not consistent in production in some repeatable way.

Or it could just be gremlins what do I know

[alan802]

It is either the mesh was not stretched perpendicular/parallel enough or the substrate you were printing on left that because of it's weave.  When we print on some performance fabric like under armour and 100% poly where the weave is super tight it will leave a pattern very much like what I see there.

[jasonl]

looks like roller frames with crooked or improperly stretched mesh.  seen it 9999999999999999999 times.

[brandon]

Yeah, could be not up to tension hence screen not snapping back quick enough from the garment leaving the mesh pattern. Could be a lot of things.

[mk162]

my bet is the substrate

[Rockers]

Sorry for not posting a reply earlier but the time difference is a killer.
it`s part of a print that goes on a white underbase onto 100 cotton tees. The film is very black and therefor I doubt that there is any emulsion stuck in the mesh. It`s one big open area, no halftones at all. Changed the screen to an old well trusted Roller Frame with a N128 and still I`m getting the same effect, not as bad but still visible. Kind of wondering if that has something to do with the white underbase? When I print the same image without underbase, just red flash red the print looks just fine. The screen tension on both frames is 40N.

[Rockers]

So I lowered the flash time of the white base to just 1 sec and that seems to have solved this problem.

[alan802]

Ok, didn't know that was a top color going on top of an underbase, I thought it was just a spot color.  How long were you flashing originally?  5+ seconds?  You always want to set your flash to just long enough, and not a second longer than it takes for the top colors to pop and actually adhere to the underbase.  You can actually still pick ink up on your finger after flashing the UB and still have bright top colors, it doesn't have to be completely dry to the touch like some tell you.  If the UB is coming close to curing then you'll see weird things like this and top colors won't bind to the UB and will rub off and wash away in some occasions. 

[Chadwick]

I've had that happen to that extreme once.
Solid fill on a 110 mesh, and the print had what resembled moire.
I had goofed on stretching the mesh somehow.
I just eliminated that screen, as it did the same on the next setup.

Perhaps it's more to do with the substrate in your case.

I've seen some weird issues with performance garments, for example.
The moisture-wicking polyester stuff can have some 'off' angles with the fabric,
causing interference with the mesh even on a solid fill.

If you wanted to achieve the effect, it would never work.