Need help setting up file for program Ai CS5 Mac

Question

Hello everyone, I am hoping you can help me with something. I am having a 20 page conference program printed through a 3rd party company.The printer sent me back the proof today and on almost every page my artwork is being chopped off.
This is the email sent with the proof today:
"               I want you to look at these spreads and tell me if this is how you       visualized your finished pages? A lot of your art is being cut off. The finished size is 11x17.       You sent pages that were 9x12, so I used them at 100% on the 12x18       press sheet. You only need to provide a 1/8" bleed, not a 1/2". You also have       bleeds on the centers of the spreads. Those should not have a bleed. Only the outside 3 edges should       bleed.
I had trouble getting all of the art to line up."
Printer Info:
They print on 12/18 trimmed down to 11 x 17 (for full bleed)
Requested bleed: 1/8
They print out of Quark
I was told I can send them individual PDFs and they will paginate them (in order and add page numbers)
I created a file in Ai CS5 with 20 artboards (one for each page of the program) Now, the trim marks should be placed at 1 inch because they are trimming 1 inch from the top and 1 inch from the bottom. The bleed should be 1/8 so 0.125 on the 3 "outside" edges. Is this correct?
I primarily do lay-outs, the person responsible for this project bailed last minute so I am a bit stuck. If I am designing it as individual pages what are the exactly dimensions, bleed, and trim marks needed for each page to be set up correctly for the printer to paginate. Should I also add a .5 margin along the edges as a safe zone or is that not necessary because of the bleed?
Let me know if I didn't provide enough information. I appreciate any help I can get. Thanks in advance!
-d

Answer 1

It is often just simpler to build your pages (or spreads) to the actual size of the press sheet.
I'll assume this is a saddle-stitched booklet.
The press sheets will be 12 x 18 inches.
It will be printed, then, as 11 x 17 printer spreads.
That means it will have a half inch (not a whole inch) between the trims and the press sheet edges on all four sides.
There will be three-eights inch between the bleed and the edges.
(This is crowding things a tad; typically one tries to allow at least a half-inch gripper margin.)
Anyway....
1. Setup the document with twenty 9x12 vertical Artboards, with zero spacing, in two columns. Zero Bleed.
(Often, depending on the nature of the content, I would choose to build such a thing as ten 12 x 18 Artboards, with content already arranged as printing spreads, thus eliminating the need for stripping. But in the following, you'll go ahead and make 20 separate Artboards, abutted in pairs, and treat these as two-page reader spreads, to make layout easy, and to accommodate artwork that may jump the gutter.)
2. Turn on Show Grid. Turn on Snap To Grid.
Rectangle Tool: Click the page. In the dialog, specify a 17 x 11 rectangle. This corresponds to your trim.
Rectangle Tool: Click the page. In the dialog, specify a 17.25 x 11.25 rectangle. This corresponds to your bleed.
Center align the two rectangles to each other, both horizontally and vertically.
3. Zoom in. White Pointer: Snap the upper left corner of the rectangles to the grid at .375 H and .375 V of the top left Artboard.
4. Convert the two rectangles to Guides. (View>Guides>Make)
5. Line Tool: Snapping to the grid, draw your own trim marks at each corner, outboard of the trim. Use .25 pt. stroke weight. Registration color.
6. Unlock Guides. (turn off View>Guides>Lock)
7. Black Pointer: Marquee select around all the trim marks and the two rectangluar Guides.
DoubleClick the Black Pointer. In the resulting Move dialog, enter a vertical movement of 12" and click copy.
Transform Again (Ctrl D) 8 times.
Now you have a set of trim guides, bleed guides, and trim marks on all 10 two-page reader spreads.
8. Create the content as if the pairs of Artboards are facing pages of reader spreads. The top pair are the front and back. The other pairs are sequentially-numbered reading speads. Set up this way, your artwork can jump the gutter when desired.  You can put other printer's marks (sep names, etc.) in the bleed area if needed.
9. Save A Copy to PDF with Use Artboards checked. The resulting PDF will contain 9x12 vertical pages. Viewed as spreads in Acrobat, you can see that the pages align.
10. But when they are printed, they will be stripped into two-page printing spreads, ordered like so:
JET