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  • Going Web

    We've been a sheetfed shop going on 50 yrs and are now in the process of installing a 5c web. Us here in prepress are wondering about the learning
    curve as far as terminology,layout,platemaking and just the day to day
    workflow that it will bring. Not really a question just fishing for other's experiences.

  • #2
    Re: Going Web

    What kind of web, how many webs will you be running. I started in sheetfed and the impo was the biggest challenge for me at first; ie going from 16pgr to a 3 web config, 48 pgr. I needed to remember to consider the inside sigs need to be adjusted towards the head on a normal layout, like creep on a saddle-stiched book. For example, we run 50# offset, I use preps and in the template on web 2 i use .005 up for the mod. page shingling and on web 3 I would double this. Sometimes depending on your stock and the ability of your folders on press you need to adjust more or less. Mind you we are using an older heatset. Also, you need to take into consideration the paper will shrink if using heatset, this will have to be tested. The adjustments will differ depending on the work, it was definitely an eye opener to me. I just printed out layouts for all of our generics and pinned them up in front of my impo station.

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    • #3
      Re: Going Web

      It's a 5/5 Rotoman. Heat set. When you say how many webs, is that how many times the original width of the roll get's slit then marries them back into sigs at the folder? If so, i heard 2. As you can tell i'm lacking in web speak. so pardon me on that,please.

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      • #4
        Re: Going Web

        I am speaking of how many simultaneous rolls are being fed at the same time. In my case we feed up to 3 at once. That is 3, 16pg, 8.5x11 sigs. We usually run 35in. rolls and have a 22.75 in cutoff. This will put pgs 1-2 on outside sig1, 3-4 on inside sig1 and 5-6 on inside sig2. It sounds like you are running a single web, which for the most part is like a sheetfed as far as impo goes, except for the shrinkage factor. Offset will shrink more than coated, at least in my experience. In my case, with the older web, they require center marks extending off the sheet edges in all 4 directions for plate alignment and bending, I would assume a newer press will not require things like this, but will probably require reg. marks in other places to check for things like web growth and fine tune registration, also will probably need compensator marks. In my case I use 3/16" square box in center of sheet so the press will pick this mark up with a sensor and front to back reg. will be held. In the case of a job that has large solid tabs, I will put the comp. marks on the left and right of the sheet so the press will not try to follow the tabs and cause the press guys trouble with backup.

        Some of these tips might not apply in your situation, so sorry for the extra parts. If it is a gapless design, meaning no grip area, I am not familiar with the requirements, could be similar.

        Good luck in your new experience, I am sure you will do just fine.

        john

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        • #5
          Re: Going Web

          We run both sheetfed and web. You probably won't be running many multi-web jobs with only 5 units unless they're 1 color. I would have to say that understanding pagination of multi-web signatures as opposed to assembling signatures off line is the hardest thing to grasp especially with half web and 3/4 web runs.

          Other than that, it just comes down to asking the pressman what kind of marks thy want on the sheet. We add a set of registration diamonds for the auto registration system on our Hantscho. They are an eps file that I use as a static mark in Preps.

          Also, you may have trouble with full bleed 8.5 x 11 if it is a short cutoff (22.75). Our Heatset has a long cutoff and can handle it but our newspaper web is 22.75 cutoff, so we run 8.375x10.875 in order to catch bleed. The news web has 22 units and we pull as many as 6 webs at times on tabloids, dual unwinds at both ends of the press! It makes for a crazy impo especially if there is a half web in the mix!

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          • #6
            Re: Going Web

            Very good point on the half web impo, if I can get my head out of the lounge I will post a pic of an 8pgr that we use tomorrow . This will be a good start.

            Wooah,6 webs, that's a lot to keep track of

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            • #7
              Re: Going Web

              > {quote:title=jbbbarr wrote:}{quote}
              > Very good point on the half web impo, if I can get my head out of the lounge I will post a pic of an 8pgr that we use tomorrow . This will be a good start.
              >
              > Wooah,6 webs, that's a lot to keep track of

              Yes it is. Here is a screen shot of a 44 pg Tab with the half web (we call it a dinky) on pg 17&18. This means that the half web is sandwiched on the high folio side between web 2&3.

              The attachment is a pdf that can be downloaded at the top of my message.

              Edited by: Earendil on Aug 30, 2007 4:00 PM

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              • #8
                Re: Going Web

                Very interesting, I am used to three full size or maybe an 8 thrown in the mix, but it follows the same layout principles as ours. One more thing to add is the naming of the different webs is quite critical as I found out in the beginning, it will bite very hard or the press helpers will. I can just imagine standing in front of your platesetter grabbing each plate as it exits and labeling correctly if you were to forget to add this sig. label. Would only happen once, huh.

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                • #9
                  Re: Going Web

                  You are very right! Multi webs are confusing as hell for everyone so proper labeling is a must! When I first started creating Preps templates for multi webs, I would place the half web in my template, in the same position as on the press. In the case of the 44 pg I posted, it would have had side A, B, C, D, then the half web, followed by the other 3 webs. This created a number of problems.

                  One of these was when sending proofs to our spinjet. The files will go into a sheetwise (2sided) queue. If I had the dink in the middle of the layout, it would back it up with the a side of the next sig instead of doing it work and turn style. It would also confuse the plating sequence. There is no such thing as a work and turn on a web press but I impo a half web as though it was a work and turn. Instead of running the paper through the press twice, we just burn two sets of plates for that form. You hang one set of plates on the top unit and one set on the bottom unit and it backs up perfectly. You end up burning extra image on the half of the plate not being used but that doesn't matter.

                  So, I always put the half web at the end of the full webs and everyone here knows that when there's a half web, it will always be the last plate, or set of plates if it's full color. It's still paginated correctly, just always the last web in preps.

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                  • #10
                    Re: Going Web

                    We have a 5/5 rotoman and there is a fairly large learning curve getting all the folder options. Depending on the color control system you bought there will need to be all of those elements to get on the plate. We have static templates for the various web roll sizes we work from with all the static marks already on them. The biggest thing will be learning all of the folds from the A101 to the F107 and what they can do.

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                    • #11
                      Re: Going Web

                      What web press are you running? Goss? Harris? Heidelberg? diddy?

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                      • #12
                        Re: Going Web

                        There is a formula for all page layouts sigs arent hard once you get used to the layout

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                        • #13
                          Re: Going Web

                          Guys,

                          I work for MAN and we have a nice desktop program that details every possible fold and includes animation of the webs and how they align on the superstructure. It also includes detailed pagination drawings. It is a good tool to help everyone including estimators, salespeople and CSRs.

                          Send me an e-mail with your cutoff and I will send you the program. It takes about a week to turn it around if I don't already have the cutoff so be patient.

                          McKay Mattingly
                          mattingly@mru.com

                          Comment


                          • #14
                            Re: Going Web

                            Hi D_max,

                            We have a KBA Continent web offset press with 8 (4c) tower and 2 monos.

                            We run 4 newspaper titles as well as coated magazines. We use 1tower for commercial purposes wherein one web coated goes to heatset. If you're running both commercial and newspaper, make sure all your path rollers are clean before running commercial.

                            Currently, we have problems with impression. We're running 90gsm, as well as 54gsm on the same tower and we just can't change packing twice every single day!

                            You may also want to make sure you get the right folder. Otherwise, the people in the bindery will have difficulty trimming the jobs. Some folders don't handle quarter folds very good. The cutting marks are so far away because the fold is too loose, even with perforation.

                            You mentioned you're in Prepress. I would use a slightly higher GCR when running on the web just to improve gray balance.

                            Lastly, maybe...just maybe, the press operators may say your plates are misregistered. At times, this can be true. But sometimes, this can also be a case of fanout problems. Some web presses have 1 or 2 levers where you can manually compensate for fanout.

                            My thoughts only.

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