Educational H20 discussion - Mark Gervais

[Rob Coleman]

Hello all. 

At the January Long Beach show, Mark Gervais - who runs a very large facility in Ningo, China -  spoke to a small conference of printers regarding the how's and what's of water base printing.  Mark is a very knowledgeable and accomplished water base printer -- High Solids, discharge, soft bases, and specialties.

M&R recorded these and have now posted them for viewing on their Facebook page.  It is a series of 6 videos - a little more than an hour combined length.  Link here to M&R Facebook page:  https://www.facebook.com/mrcompanies?fref=ts

You can also google "Waterbased PVC-Free alternatives".  The link to the first YouTube Clip follows: 

Part 1 of 6 - Waterbased PVC-Free Alternatives - Separations/Film Output

Take a look/listen.  You might gain a few "pearls of wisdom"!

Rob

[ZooCity]

Looking forward to checking this out, thx.

[jsheridan]

I've watched the first 3...

pure gold

[Homer]

I thought you wanted a thinner stencil/eom with wb printing....time to try something new on Monday..also interesteing to apply the hardener when the screen is still wet fronm washout. I thought we had to let it dry after washout, then apply...

[brandon]

This is awesome. Watching all of it later today after running errands. 52 autos.... holy smokes!

[Colin]

Homer:  He's using the HSA (High Solids Acrilic) stuff from Rutland (along with Magna Colors formaldahide free discharge).  He is using the thicker stencils for the HSA inks.

Small bit of anoyance, he uses dpi to describe lpi.... I still would like to know how he gets 60 dpi (lpi) on his 135 LX and 160 screens.

Even with the super thin threads he uses, there has to be a lot of dots falling on top of threads...

I use the 150 LX and 180 LX mesh and I love it!  Still not sure how he accomplishes 50/60 lpi on it...

[Rob Coleman]

Colin: this is a good question.

To the group: if you have any questions for Mark, I will be working the Magna booth at FESPA in London end of June. Mark will be doing seminars on the booth. I will be happy to ask and post here.

Rob


Sent from my iPhone using Tapatalk 2

[ZooCity]

Haven't watched this yet but Colin, we run 55lpi on 150/48 and 180/48 S or LX.  You will not get dots in certain % ranges of course but it will hold that lpi surprisingly well.  This is with a thinner coating of emulsion, 2/1 on the thin edge.  Typically done with art that doesn't need the 0-20% or 80-100% dots on that screen.

It gets confusing with thin thread mesh b/c they are insanely versatile.  That same 150 can be coated all the way as thick as 2/2 round edge and throw down a plastisol ink deposit that rivals any 110 out there. 

135/48 holding 60lpi?....hmmm, it could work.  Theoretically it could work just as well, better in fact than the 150 or 180 as they all share the same thread size and lowering the mesh count only leaves you with higher odds of not landing a dot on a thread.  You would need an emulsion with fairly incredible bridging properties to get a thin, even stencil that will hold out for you through resolution and printing.   Done right I bet you could get 20-80% on the 135 with the thinnest possible EOM and excellent, I mean imagesetter or near imagesetter, films.   But I'm also presuming that was misspoken.

[GaryG]

I'd say from comparing specs with the different meshes: the approx. 10% more open area,
thinner thread with the LX- and -high quality, high solids, dense emulsion, hardener
and top line film output -- mainly the emulsion almost holds dots in suspension by itself.
As Zoo mentioned incredible bridging properties.
 

[brandon]

Colin - thank you for turning us on to the LX. Kelly dropped off some two weeks ago. I am sold.

[Inkworks]

Even with the super thin threads he uses, there has to be a lot of dots falling on top of threads...

One of the better things I picked up from watching the videos is that EOM help fix that, as he mentioned as long as there is even a partial path, the ink can still fill the whole dot after it gets past the mesh.

[ZooCity]

the emulsion almost holds dots in suspension by itself.

Yep.  I think this is why you can hold so much more on thin thread with the right emulsion/stencil.  Your minimum EOM is lower with a thinner overall mesh thickness and your open area is higher.  It puts a lot more on the emulsion than standard mesh. 

[Colin]

the emulsion almost holds dots in suspension by itself.

Yep.  I think this is why you can hold so much more on thin thread with the right emulsion/stencil.  Your minimum EOM is lower with a thinner overall mesh thickness and your open area is higher.  It puts a lot more on the emulsion than standard mesh. 

You are right Chris.  I have found to many emulsions that just don't have the right "bite" for fine detail on either the 135LX or 150LX.  The detail just washes off because of the lack of surface/threads to grab onto.  The better the emulsions "Bite/Grip" the better you can print with those meshes.  I found a couple that hold great, but they both have drawbacks.  I have a Nuarc 3140 1200w Metal Halide unit.  One emulsion from Ryonet which is a CCI product, the screens end up sticking to the exposure unit when it gets warm after 2 screens.  It only happens with the LX thread however....  It also grabs the waterproof image on my films and rips it off.  Again, only on the LX mesh.  I have an idea why, but it's hard to put into words, and still doesn't make sense.  And recently the Murakami Aquasol HV.  It worked amazingly well.  I loved it!  Only drawback is it's low flexibility/brittleness.  The edges of the squeegee can wear through the emulsion within a shockingly few number of print strokes.  Regardless of post exposure/hardening/right off the exposure unit.  So the search is on for a new emulsion

I have talked with both Kiwo and Ulano and neither one has done ANY testing on the LX meshes.... I had to explain to them what we as a group have seen, while throwing in my own personal experiences with the mesh and how each emulsion has reacted.  They were very good conversations.  Hopefully Ulano has a good single part that will do well with the LX.  Going to try the QT Discharge next week  Kiwo's suggestion fell flat unfortunately.

If I had a stronger exposure unit, it would not be an issue as Dual Cures work amazingly well.

Even with the super thin threads he uses, there has to be a lot of dots falling on top of threads...

One of the better things I picked up from watching the videos is that EOM help fix that, as he mentioned as long as there is even a partial path, the ink can still fill the whole dot after it gets past the mesh.

Right, that's because of the unique flow properties of both waterbase and HSA waterbase inks   I'm loving them more and more each day.

Rob:  Thanks for the link and the start of some great conversation!

I guess the main question about his lpi/mesh combo is the tonal area he is able to keep.  Where is he loosing dots?  Is he keeping 90% open?  80%?  Is he able to hold down to a 5% dot?  3%?  What is it for each mesh count?  And yes, we are all aware (hopefully) about making sure our films/output device are calibrated correctly and our screens are exposed correctly and a 50%/75%/10%  dot on computer/film/screen all look the same

The end result:  His prints look amazing!  So yes, he is definitely doing something right!

[Colin]

Haven't watched this yet but Colin, we run 55lpi on 150/48 and 180/48 S or LX.  You will not get dots in certain % ranges of course but it will hold that lpi surprisingly well.  This is with a thinner coating of emulsion, 2/1 on the thin edge.  Typically done with art that doesn't need the 0-20% or 80-100% dots on that screen.

It gets confusing with thin thread mesh b/c they are insanely versatile.  That same 150 can be coated all the way as thick as 2/2 round edge and throw down a plastisol ink deposit that rivals any 110 out there. 

135/48 holding 60lpi?....hmmm, it could work.  Theoretically it could work just as well, better in fact than the 150 or 180 as they all share the same thread size and lowering the mesh count only leaves you with higher odds of not landing a dot on a thread.  You would need an emulsion with fairly incredible bridging properties to get a thin, even stencil that will hold out for you through resolution and printing.   Done right I bet you could get 20-80% on the 135 with the thinnest possible EOM and excellent, I mean imagesetter or near imagesetter, films.   But I'm also presuming that was misspoken.

Chris:  Yea, we typically will coat 2/2 with sharp side slow coat.  We get amazing plastisol coverage with it!  I was in love with it the first time I put it on press.

As for the halftones, yea... I have done that before with thicker thread mesh as well.  It was something I actually used to recommend when people needed more opacity from a halftone underbase.  Done right it's awesome.  Depending, an underbase with a 60%-75% fill at 45-60 lpi worked great.  Always test before production! 

I was assuming, in Mark's situation, that he is keeping a full tonal range on the 135/150LX

And, oh heck yea, it's very emulsion dependent!

[mraph]

Rob
thanks for posting this i just finished watching all of them , Great Stuff

Alan