Mesh pattern present in top color

[jerryperrish]

I'm printing a job right now and noticing something that I never have in the past.   I have great coverage with my underbase, but when I go to lay down the top layer, I can see the mesh pattern in the print.  It's not CRAZY, but definitely there.  A flash and second hit takes care of the problem, but obviously I'd rather save the time and ink.

Any thoughts on why this could be happening? 

[Frog]

I may be starting to sound like a broken record (a broken what???LOL) but a pic would help if you can focus closely enough.

[kirkwad]

Your top color is probably on too low of a mesh. Try a higher mesh, 180 to 230. If your base is on a 110 or lower mesh, try a 125 or 155.

[screenxpress]

I read it a couple of times and it almost sounds like "great coverage with my underbase" is a solid lay down, not a halftone and the top layer "see the mesh pattern in the print" is halftone where some of the underbase is showing through the dots on the first stroke. 

Perhaps more information will follow.

[Dottonedan]

I haven’t experienced this myself, but I read on here a couple times about issues like this from using the same mesh as the base. I don’t know how much that holds water. We have used a 230 mesh on all screens before with no issues. Maybe it depends on other variables?

[jerryperrish]

Sorry for the lack of information/photos.

Both screens are spot colors, so it's not like I'm getting a moire due to halftones.  It's a super simple design.  The top layer IS a fairly low mesh though.   I'll try a higher and see what results I get.  It's funny, because my thinking is/was that the lower the mesh, the more ink, so I would think that would avoid this issue, but maybe my thinking is off. 

[Rockers]

I read it a couple of times and it almost sounds like "great coverage with my underbase" is a solid lay down, not a halftone and the top layer "see the mesh pattern in the print" is halftone where some of the underbase is showing through the dots on the first stroke. 

Perhaps more information will follow.

Unfortunately not, we had this too on a simple 1 spot color job. Second screen left this kind of wave like pattern. You could see it more or less depending on the angle you were looking at the print from. We fixed it by remaking one of the screens.

[Rockers]

Sorry for the lack of information/photos.

Both screens are spot colors, so it's not like I'm getting a moire due to halftones.  It's a super simple design.  The top layer IS a fairly low mesh though.   I'll try a higher and see what results I get.  It's funny, because my thinking is/was that the lower the mesh, the more ink, so I would think that would avoid this issue, but maybe my thinking is off.

Same happened to us, spot color job, first screen 120-S for sure second screen I@m not sure anylonger but either as well a 120-S or a 150-S. Not sure anylonger but we remade the second screen which fixed the problem.

[Nation03]

Same thing happened with me using Navy ink on a white UB. Comes out lighter and has inconsistencies. I ended up flashing it and hitting it again to solve the issue but I'd like to avoid that. I did a job a while back with a cardinal ink and had to do the same thing because it lightened the color too much. I think I was using 225-S to over print for both. I'll try a lower mesh next time.

[Sbrem]

Sorry for the lack of information/photos.

Both screens are spot colors, so it's not like I'm getting a moire due to halftones.  It's a super simple design.  The top layer IS a fairly low mesh though.   I'll try a higher and see what results I get.  It's funny, because my thinking is/was that the lower the mesh, the more ink, so I would think that would avoid this issue, but maybe my thinking is off.

Lower mesh also means thicker threads...

Steve

[Frog]

Sorry for the lack of information/photos.

Both screens are spot colors, so it's not like I'm getting a moire due to halftones.  It's a super simple design.  The top layer IS a fairly low mesh though.   I'll try a higher and see what results I get.  It's funny, because my thinking is/was that the lower the mesh, the more ink, so I would think that would avoid this issue, but maybe my thinking is off.

Just to clarify an oft-occurring error in terminology.
Spot colors have nothing to do with whether they are solid or halftones. It is rather the term used for a color printed with its own single ink (as opposed to one composed of different inks like in CYMK process printing)

[ZooCity]

Does it look like a weird moire pattern?  If so, we get this all the time when both UB and top color is on the same mesh and the UB is super opaque, i.e., high EOM on UB screen or the UB is revolved, etc.   

We switched to lower EOM for the UB screens and most of the problem has gone away.  Seems like the issue is maybe present always but not visible to the eye until you magnify by making too strong of a UB.  Just the running theory around here at least.

[ebscreen]

We switched to lower EOM for the UB screens and most of the problem has gone away.  Seems like the issue is maybe present always but not visible to the eye until you magnify by making too strong of a UB.  Just the running theory around here at least.

Was thinking about this recently and I think you're right. The idea I had was that less of an opaque base deposit would allow more
shirt through, breaking up the pattern and making it "invisible" to the eye. That is unless the fabric weave pattern starts to interplay with
the mesh pattern (we usually see only on higher mesh screens) and that's a whole other frustration.

[ZooCity]

What's kind of weird to me is that ironing (on press iron after flash) the UB doesn't remove it.  You'd think if you are slightly remelting the top layer of the film it would eliminate the patterning, especially with thin thread mesh.