screens for sim process?

[Screen Dan]

Hey Dan, curious on the choice of 180/48 over 150/48.  We employ both but the 180 is really there for the plastisol jobs that need better "snap off" since they run at a higher ten.

I love, love, love simplifying mesh count selection, it eases so many parts of the process form pre-press to screen to production, purchasing and onward.

Also, are you linearized per mesh count?  i.e., the CTS has one curve for 55lpi on 180 mesh, another for 55lpi on 225?  sounds ingenious or maybe problematic, I can't tell which, but it's intriguing.

We were heavy on the 150/48 for years, but our emulsion started delaminating and we tried everything...the only thing that worked was abraiding while degreasing.  150/48 is fragile enough as it is.  We switched to 180/48 and nobody said a single thing.  We keep 150/48 around for extreme circumstances, which we have yet to encounter 6 months into the transition.

We're singularly linearized across all mesh counts but use slightly different curves for 53lpi (don't ask), 55 lpi and 60lpi.  I've toyed with the idea of different calibrations for different meshes but it would be too much a pain to implement given our RIP's simple workflow, though I might be able to pull it off repurposing the X-color process workflow side of the RIP.  I haven't been that bored yet.

...But if I were to do per-mesh-dot-calibration, in an ideal world, I'd use 150/48 and 300/40 for everything.  300/40 is good for nearly 40nm² and is damn near indestructible.  We've retensioned it with giant holes in some pretty damning places, with no problems...but without a separate dot calibration for it the ink just doesn't flow enough without modification, which we hate doing...and trying to get that same dot calibration to be useful on a baseplate mesh was frustrating.

...and yes, we do WB/DC (never messed with HSA) just fine on those same mesh counts and curves.

[ZooCity]

This is a great thread.  We do a good grip of spot/sim and have to repeat it, dead nuts on, over many runs during a season, a year or longer and they are almost all sold at retail.  I have a total hard on for the concept of reducing mesh selection, I feel it can only lead to better consistency.  Hard to give up the unique attributes of certain meshes though.

On the 150/48, there are emulsions that will grip it tenaciously and hold very high detail for baseplates though some comprise may be needed on eom, depending on what you are going for. 

I think Murakami or someone should release a high res, ultra high bridging emulsion for use with open mesh specifically. 

Agreed on wb/dc working across most all mesh counts.  HSA is a different beast in our climate and we direct it to the mesh with the very highest open area and it can still be problematic on press-  trade off on the ink side for longer open time v. coverage nearing or at the level of plastisol.  Seems like the humectants currently used in these inks might interfere with opacity.  Part of our solution has been very open mesh counts.

[Screen Dan]

This is a great thread.  We do a good grip of spot/sim and have to repeat it, dead nuts on, over many runs during a season, a year or longer and they are almost all sold at retail.  I have a total hard on for the concept of reducing mesh selection, I feel it can only lead to better consistency.  Hard to give up the unique attributes of certain meshes though.

We do lots of re-prints and everything has to match stock every single time.  Reducing the amount of mesh counts we had definitely helped us achieve this and also had the effect of virtually multiplying the amount of screen inventory I had.  Simplicity is everything.

That was my second big move when I took over the screen department.  It rattled some cages for sure, but after spending 8 years running a press I knew damn well it was the right direction to go.  So, to shut up the whiners (and for genuine but rare legitimate circumstances) I keep a handful of 110s, a handful of 150s, and a handful of 300s which we rarely ever use.

The first step was to calibrate those damned dots.  Nobody ever thought to do that.  When we got our second CTS it came with it's own external RIP computer which would traditionally go in the art room.  Thankfully they had no room for (and even less desire to tinker with) it so I got it on my desk.  If I had never got a hold of that I'd have never gotten to play with the nitty gritty details and we'd still be pumping out 45-LPI non-calibrated RIPs that would most certainly require that wild array of meshes for any manner of random reasons.  Want superfine halftone detail on your black plate but also need to saturate 100% spots?  That would turn into a mess of 355s and 280s with varying degrees of squeegee voodoo and press voodoo, depending on the operator.  Either too dark but the 100% spots are filled, or looks right except the fill spots are spotty.

Mesh cost came down since I was able to angle for a better price since we were buying far more of only two meshes, ordering and stocking and labeling became effortless since we were only dealing with two meshes.  The racks of ready-to-burn screens weren't a mess of meshes.  There's the white plate rack and the color plate racks.  Reclaim got simpler since I didn't need to hit the floor and pick out which screens needed to be washed and reclaimed.  Scheduling pre-production became easier since I didn't have to balance what needs to be done versus what I can do versus what I need to get reclaimed.  Now we just prioritize the jobs and print them in order with no juggling jobs to make up for those 6 280s I need to get back off the floor.  Retensioning became easier with only 2 tension standards to remember.  No more charts, no screen catalogs since  I know we have 600 frames and roughly 1/8th of them are white plates.  Done.  You can easily tell a 150/180 from a 225 from across the room based on the emulsion deposit.  The exposure unit only has two programmed settings...before we'd run out and have to reprogram certain slots all the time.  Now we have a color plate setting, a white plate setting, a few high-solids thick stencil settings for different thicknesses and a "burn the crap out of this" setting for post exposure.

I really can't say enough great things about the move.  If you do repeat jobs and do mostly sim. process+spot it's probably a great move.  It was for us.

[mimosatexas]

This is (almost) completely off topic, but what inks are you running Dan? Like specifically...(brand/series/etc)

[Sbrem]

We also do a lot reprints, we just keep records of the normal things; mesh, print order, squeegee, pressure and angles, etc... It's almost always fine, but if not, it's real easy to figure out...

Steve

[Screen Dan]

This is (almost) completely off topic, but what inks are you running Dan? Like specifically...(brand/series/etc)

QCM colors, Quick White for UB.  Anyone who's played with QCM's whites (any of them, really) knows why.


...I'm not positive what the mixing colors are, but if QCM offers a system I'm sure that's what it is.  We're a pretty large operation so outside of the screen department/pre-production and all the buying/sourcing I'm out of the loop and that manager is free to use whatever the hell he wants.  Luckily I can trust him to not be an idiot.

[prathap]

225S for base plates

270 or 330 mesh for top colors

[prathap]

Yes its indeed a bad news.