Really tight CMYK printing onto fabric

[{LG}]

Ok, check out this book, Photoshop CS3 for Screenprinters. It was kinda useless to me because I do sim process wherever possible...which has been everything so far, I've yet to have a need to print 4cp, but the 4cp section is thick and looks like a good primer for doing it all out of PS. There's a disc with sample/practice files that go along with the sections. I'd still recommend getting a job sepped out for you. Study the channels from the separator to get a feel for how it's done by someone with experience and consider it an investment. For the cost of seps though, I usually just roll it into the pricing and save myself the time. I do enjoy separation but there's only so much you can do.

I like sim process because it's more forgiving, works over a variety of colors/substrates better and is more repeatable, but if you can do higher end sim you can do 4cp. I would expect to use a bump plate or two for colors that aren't going to reproduce well in cmyk or need to be spot for branding or just to make the art work.

General pointers:

• Don't combine any solid text fills onto the same screen as your halftones, you'll need an extra black screen for instance if there's solid black fills. Very good seps will stack up the cmyk colors to sometimes achieve this but that's trickier.
• Decide if you want to angle each color to achieve a rosette pattern or set them all to 22.5 degrees and go. There's a lot of debate on this I believe but I find the latter to be best on textiles, generally speaking. Regarding the former, there's as many rules for those angles and the print order as there are printers.
• Related to the above, keep in mind you are not only fighting moire from the film to the mesh in this scenario but also interference from the weave of the garment so chose those angles wisely. Have plenty of backup screens in case something goes totally fubar on you.
• On white Ts I'd use a 310/30 or 330/30 mesh at 60lpi at around 22 n/cm. For standard, thicker mesh thread get it up as high as it will go in tension if using retens. If not, just use good screens and keep in mind that lots of high end work is done on static frames everyday, it's just tougher to get it setup and you'll have more of a hand to the finished print.
• Use a good rip for film output and take a second to dial that all in if you haven't already.

A lot of that is probably really obvious but good luck!

[michael_0]

No man, that's great advice, thank you!

[RichieGoodtimes]

It's my professional opinion that anything over 45lpi is an u unnecessary headache, especially if you've never printed process before. Also, I like using the same angle for sim process but prefer rosettes with true process.

[{LG}]

It's my professional opinion that anything over 45lpi is an u unnecessary headache, especially if you've never printed process before. Also, I like using the same angle for sim process but prefer rosettes with true process.

whoa, 45lpi for process? I sort of go 'ick' at anything under 50lpi. Is this just for the sake of having control? Got some examples?

[patoakes]

It's my professional opinion that anything over 45lpi is an u unnecessary headache, especially if you've never printed process before. Also, I like using the same angle for sim process but prefer rosettes with true process.

^^ Listen to this guy ^^

[michael_0]

^^ Listen to this guy ^^

Heh. Kay....

Richie, if you have any pics you can post, I'd love to see em as well.

[deadmeat]

i do 35lpi, and my angle rotation is C22, M52, Y82 & K112. Works swell for me on paper...

[RichieGoodtimes]

The thing with t-shirts is that your average viewing distance is about 4 feet. You can't see the dots at 4 feet, so it's not crucial to use tiny dots. It's not like a magazine at 133lpi where the viewer is right on top of the image. 45lpi is more than adequate. Only printers and the customer get right on top of shirts and stare at the dots. 45lpi dots are going to give you greater saturation with less effort as well. 45lpi on a properly tensioned 230 with the thinnest emulsion deposit possible is my recommendation.

[B-DROID]

I think a lot of it comes down to what you are comfortable working with while starting out, Michael. Maybe you want to start out with a larger dot to get a feel for the process and for ease of trouble shooting things that you will have to deal with like dot gain and possibly moire. The larger dot will definitely be easier to work with when starting out. We generally leave it up to our factories to decide which dot size they want to use, but in the past I've recommended Sim-process at 55lpi with 60º.
Maintaining a nice tight rosette pattern is going to be key to producing a great image and the tools you're using are going to be the basis for that. Like Richie and others have mentioned, properly tensioned screens and a nice sharp (stiff too) squeegee are key in this. Figuring out your screen angles will be key in avoiding moire, standard angles + 7º should get good results but you might need to adjust since you're on metric mesh.

Seps are fairly easy. CMYK mode in photoshop will get you 90% of the way, from there its a matter of adjusting your curves to get the image the way you want it to look, then pulling them back a bit to compensate for dot gain.

With all that being said....Unless it is specifically requested we don't do straight CMYK-process work at my job, it's all Simulated / Spot process stuff, and there is a reason for that. It's easier to print and get great results from. If you are wanting to print photo-real images with CMYK, it's going to be a tall order for you especially if you have a picky client. But, if that is the case I would source a printer that print digital transfers at 1200dpi and roll with that. The technology and durability of the print is there now.

[RichieGoodtimes]

When I do sim process on darks...always 45lpi. My goal is always maximum saturation with minimal ink deposit and the trade off is that I get more pigment in a larger dot than I do in a smaller dot.