TSB
screen printing => General Screen Printing => Topic started by: Itsa Little CrOoked on May 01, 2014, 12:41:05 PM
-
This probably should be easy but for me, it isn't. The print area is about 11 x 15 inches.
The stroke on a capital "T" measures .018 (or just over 4 thicknesses of a dollar bill) and the cavity in a lower case "0" is .058 (13 dollar bills)
I am a manual printer, so if this were black ink prints on lights cotton tees, I'd shoot a 305, do a heavy flood stroke and two moderate push strokes with a sharp 70-90-70.
But with white plastisol ink, I'm clueless. Can't discharge it because there is a handful of colored blanks, some of which won't discharge very well. Am I over thinking this? Poor sleeping and no breakfast makes for feeble minds.
I know that tiny details with white plastisol don't require so much opacity as do big clumsy blobs. And since it's just one plate, I will no doubt experiment some.
I think I'll grab a 195 (static, ~22 newtons---I know. I know.---2 over 2 with the sharp edge) and see what happens.
My press *might* not hold tight enough for a PFP but that might be a way to get this OUT THE DOOR and get on to something that works better.
Thanks,
Stan
-
Try using newman frame with 230 mesh PFP
I did some small text last year with 195, but it was not THAT small. But I think that 230 will do the trick. It also depends if you have good exposure unit to expose it.
In the end, it will be a bit crOoked anyhow :)
-
Also a 225/S mesh will allow for lighter squeegee pressure to keep white ink opaque. 42% open area on 225/S mesh vs 33% on a 225T. Tension on a newman 24-25 newtons.
Al
-
I haven't ventured into S-Mesh yet. I could get some in before the job goes out, I think. Pretty sure I don't have any on hand.
Can I stretch it and print it the same day? The run isn't big and it's one color. SURELY it wouldn't drop off too bad for 80 PFP prints.
Should I try for a thicker stencil? I really don't worry too much about EOM. Lots of my work is with discharge nowadays. I do have a micron gauge. It mostly just collects dust. ::)
-
Also a 225/S mesh will allow for lighter squeegee pressure to keep white ink opaque. 42% open area on 225/S mesh vs 33% on a 225T. Tension on a newman 24-25 newtons.
Al
I was just about to recommend the same. It probably depends as well a little on the emulsion you are using too.
-
We've run into this with sponsor backs on occasion; 2 - 280's or higher, but we like 280. PFP
Steve
-
280. TWO EIGHTY?!?
I jump from 230 to 305 (embarrassed) but I've been wanting to stretch some S mesh anyhow. I know the open area in a 280-S would be a whole different ball game than I'm used to. No time like the present.
YOU GUYS DID GET that this is WHITE plastisol? Just checking...... I've never had good luck pushing white through fines, but they're standard diameter threads.
-
I haven't ventured into S-Mesh yet. I could get some in before the job goes out, I think. Pretty sure I don't have any on hand.
Can I stretch it and print it the same day? The run isn't big and it's one color. SURELY it wouldn't drop off too bad for 80 PFP prints.
Should I try for a thicker stencil? I really don't worry too much about EOM. Lots of my work is with discharge nowadays. I do have a micron gauge. It mostly just collects dust. ::)
Just ran back and checked a 330S and its at 22Nm from 26Nm, with well over 2,000 impressions between 2 jobs. We are in the process of testing S mesh now and so far I am pleased.
Chris
-
I wouldn't lie to you, I don't know you well enough, LOL. Yes, 280T, we didn't have the S the last time we did one, thin the ink, and be sure to only use that bucket for this kind of thing... I've pushed white through 305 since the '70's, it just has to be thinned. With a lot of "one color" whites, we will print the whole image with the 280, then a 200 - 230 for the heavier parts; bright white and great detail... good tension, stencils, the right blades and the rest is assumed.
Steve
-
150/48, one stroke, onto belt.
-
150/48, one stroke, onto belt.
But would you guys worry about EOM?
I'm 2 over 2 sharp edge on every frame....not that I couldn't go for a thicker stencil. I just don't. An auto is still a ways off (so I cheat).
-
I would just coat the screen with the glisten method and the round edge, at our shop a 150/48 takes a 2 over 1, which would put it around 20% EOMR. I wouldn't concern yourself too much with the EOM as long as it's not really thin, or really thick. Too thin and your ink deposit will suffer along with edges not being crisp, too thick and the ink doesn't shear without a lot of pressure and a really soft squeegee. That type of an image is tailor-made for a one hit print.
-
I'm thinking I should have looked at the art first ( I didn't notice the link) so I'm with Alan, one hit onto the belt, we use 140 here. Nothing problematic with this art. When I said 280, I was thinking considerably smaller type...
Steve
-
Ive been manual printing detailed whites through 225S statics recent, coated 2/. Doesnt even need a clearing stroke. The s mesh is the bomb.
-
I've done text like this on a 150-S. Works like a charm. That mesh is gold.
-
T
I think I'll grab a 195 (static, ~22 newtons---I know. I know.---2 over 2 with the sharp edge) and see what happens.
fine detail on a sloppy thick stencil screen is just asking for trouble.
coat 1x1 and try and find a screen with better tension.
-
I would disagree to a point. I know my 2/1 coats with round on a 225S have some serious eom. I find that the higher walls of the stencil combined with the S mesh allow a significant amount of opacity with minimal pressure and the detail is nice and crisp as a result.
-
John is right about the thick stencil not being a good choice for high detail. Its just not what you reach for when needing high detail. Can it be done, sure. Can it be done every time. No. I have printed white ink on a 305 manually and got great opacity and detail. I have even printed 45 lpi dots on a 123 with great results. You really need to look at your goal. The fastest, easiest, normal way does not always result in the best results. Each shop is different and even our definition of good opacity and high detail will differ.
-
The question is, what are you guys considering "sloppy thick"? My everyday glisten method coatings, which Alan802 measures at close to 20% EOM, are thick compared to what I typically used twenty years ago, but not what I would use if shooting for a specifically thick deposit.
Myself, printing manually with statics on hand, I'd go with a 160 or 140 (standard mesh) and probably get fine coverage on these little guys without a flash and second print. That said, next time I re-stock, I'lll be adding some s-mesh.
-
It seems like there is to much concern about opacity. But when you are printing such thin lines with white opacity is nothing to really worry about in my opinion. Like Alan said hit it and send it down the dryer, the difference between 100% opaque under a loupe and 70% under a loupe is not really going to be noticeable by eye.
-
You have a 195-55, you're looking at about 80-85 microns mesh thickness, 100 microns with 20% EOM. 1x1 that and get 5% EOM and you'll likely clear a 10-15% smaller detail than a 2x1.
AFAIK, Stencil thickness=maximum dot or detail dimension that clears well....
The thing is: Unless I read you wrong, your smallest positive detail is .018--this is over 450 microns... not sure why this should be any sort of problem.
Kinda wondering though, a point is around .014, and that's cake for me on a 160 standard thread with no special handling... it's the NEGATIVE details that usually catch me. ;)
-
I don't think he'll have any worries at all with this, he just needed a little reassurance. If you do have time though, and this is the way I learned a ton, make a few screens with this image and do some test printing and measure, analyze, repeat till you get a grasp of what each change in parameter does to the print. Next time you'll make decisions based off what you learned while test printing for 30 minutes. Print the image through the same screen with different blades, and obviously compare like blades with different mesh counts, fast stroke, slow stroke, hard flood, light flood, push stroke, pull stroke, etc. This is a great opportunity to learn more in 30 minutes than you would all day searching this forum.
-
On coating techniques, I've always used the sharp edge, whether it was to be a thick or thin stencil was in the touch (very scientific, I know). I used what Andy and others refer to as the glisten method for my heavier meshes, and thinner, not so "glisteny" for finer meshes. I seem to recall that Joe Clarke, fairly venerable, wrote that thinner coats are better for high detail...
Steve
-
On coating techniques, I've always used the sharp edge, whether it was to be a thick or thin stencil was in the touch (very scientific, I know). I used what Andy and others refer to as the glisten method for my heavier meshes, and thinner, not so "glisteny" for finer meshes. I seem to recall that Joe Clarke, fairly venerable, wrote that thinner coats are better for high detail...
Steve
Joe typically goes by "just thick enough" so that can mean a lot of different things depending on the application being used. So in his method you'd shoot for being right on the verge of the stencil being too thin to do it's job properly. We usually miss on the thicker side of "thick enough" just because we spent years printing through really thin stencils and if for nothing else other than avoiding all those old headaches I err on the side of new problems :). And add in the fact that we haven't had many issues with a stencil being too thick we lean towards the thicker side than thin and always coat with the rounded edge. I just feel like it's easier to get a thick stencil with the round edge and if I want a thin stencil it will do that great too. Even with some of our really thick stencils we've managed to shear the ink with one pass but I'll admit that a softer blade, slower print speeds and higher pressure was needed to do it.
-
The funny thing is, I never noticed the rounder edge other than as a warning to use the other edge, LOL. For me, my thicker coatings for heavier meshes came just after filling the coater, usually 2 screens, 2 coats shirt side, 1 coat print side, dry horizontally to let gravity help a little. Yes, they do "glisten".
Steve