Screen printing & controlling size of dot pattern in gradient halftones gradien

Question

I'm using A Mac OS 10.6.8, and Illustrator CS5.
I do garment screen printing.
In my designs I use a gradient, which needs to have the halftone dots controlled, and a certain size, to expose properly on my screens to then print.
I can't seem to figure out how to adjust the frequency or LPI, and the angle so that they work. It still prints out as a seen on screen
Thanks ahaead of time for your reply.
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Answer 1

Mark,
I answered your questions in my previous post.
As you can see, the dot size is much smaller as the DPI is increased.
Of course. As I explained, the higher the halftone frequency (the standard term for which is Lines Per Inch, not Dots Per Inch); the more halftone dots per measure; therefore the smaller the dots.
Once converted into halftone dots, just select > expand appearance...
As I explained in response to your question about the screen printer being able to edit the "halftone" settings: If the plug-in applies a live effect, the printing house would have to have the same plug-in to alter the effect settings. (He'd also have to have a sufficient proficiency in Illustrator, which you cannot assume.) If you expand the effect, it's then "nailed down" as non-live paths and the printer will not be able to change the LPI.
Honestly, you should take a look at their plug-ins, they're amazing!
It's not that amazing. I have my own scripts which do pretty much the same kind of faux halftone.
This is not actual halftoning. In a real halftone, the dots change shape as they cover more area. Look at a printed grayscale ramp with a loup and you'll see that as the tones cross the 50% range, they "morph" from black dots on a white field into white dots on a black field; they don't just become larger and larger black dots choking out the white areas.
Nor is this the same thing at all as a drawing program properly providing object-level halftone settings, as does FreeHand. FreeHand lets you assign actual PostScript halftone settings at the object level. The printer's RIP builds the halftone as true halftones at print time. For example, in FreeHand, you can set an object to print as a line halftone pattern at 30 LPI, and another object to print as a diamond halftone pattern at 50 LPI. Both halftones are applied by the printer, not by actually drawing a kazillion tiny paths in the FreeHand document. This is just one of those areas in which Illustrator is still decades-deficient in providing valuable functionality.
So, I'm just trying to figure out the best way to approach this.
Again: Assuming your concern is just to be able to print a halftone ruling that the printing house can hold, you need to find out from the printing house what that halftone ruling is. Just saying it's screen printing is not enough. Screen printing shops run the gamut from small mom & pop shops using an almost entirely manual process to high end large outfits running very large, elaborate, and expensive equipment--and everything in between.
As a general rule, halftoning really doesn't look very good on garments anyway--especially when done by small-to-medium shops--because of the course halftone rulings required. Talented and innovative screen-centric designers and screen print houses avoid actual halftones and actual process color, and instead utilize clever hatching or stippling techniques in the artwork, often involving multiple additional inks (several greens, for example). The result is vibrant, brilliant color, because it's really rendered as posterized solid line art. Next time you're at any mainstream department store, take a look at the most brilliant T-shirt pictorials--the ones of dinosaurs and colorful fantasy images. Study them up close and you'll see they are not ordinary process or ordinary halftoning.
If I were using Illustrator for something destined for T-shirt printing, and using tint screens not intended as a special effect, but just as an attempt to minimize ink count by overprinting a small set of opaque spot inks in a process kind of way, I would simply set the halftone settings for the ink at the document level at print time--which is all Illustrator can do.
...tell me exactly what to ask the printer...
Again: Ask the printer what is the highest halftone screen ruling he can reliably and consistently hold. Then it's up to you whether that's good enough for your satisfaction, or if you need to find a more capable screen printing shop, or whether you need to redo the artwork  using a lineart method for suggesting tones.
JET