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Extravoice
2012-Mar-05, 01:17 PM
Anybody on the board know about the newsprint business?

While reading the local newspaper over breakfast this morning, I noticed three 2"x2" white post-it-like tabs stuck onto two adjoining pages. The paper's "content" was printed over the top of the tab. The glue on the tabs was sort-of "opposite" of a post-it, with most of the back of the tab glued to the sheet, but a with about 1/2" of the top edge glue-less. The glue seems to have been intended to be permanent (unlike a post-it).

Does anyone have an idea of their purpose?

Here are some more clues:
The two pages that had the tabs were the comics and the sports "box scores."
Holding the tabs up to the light (and careful removal of one) showed no indication of an attempt to cover-up a printing error or paper blemish, and the reverse side of the page showed no indication of a hole or other damage to the page. The tabs showed signs of perforation at the glue-less edge. The glue-less edge was oriented toward the top of the page, and the tabs were "square" with the page.

Ideas? :think:

HenrikOlsen
2012-Mar-05, 02:43 PM
I think this would be Staiduk's area of expertise, but since he's away at the moment, I'll hazard a guess which would be something like reinforcement of the leading edge for use when feeding the paper from the rolls into the press.

Extravoice
2012-Mar-05, 03:11 PM
I suspect you may be on the right track, and they are related to paper handling automation.

Upon further inspection, I noticed that the three tabs were all on the same sheet of paper (which is folded to create four pages). The tabs were also aligned horizontally little lower than halfway down the page. I also spotted part of a fourth tab on the right edge of the page, which had apparently been cut with the paper.

Trebuchet
2012-Mar-05, 04:07 PM
I'm thinking it's something to trigger an optical sensor that the end of the roll is approaching.

Jim
2012-Mar-05, 05:47 PM
Nonsense. The newspaper publishers simply realized that this is Really Important Stuff and didn't want you to miss it, so they bookmarked it for you.

Staiduk
2013-Jan-20, 07:06 AM
Well, this is many months old; you will have to excuse me - I've only got the Internet back in the past couple of weeks. I'm aware I'm 'necroposting'; but I'm a little drunk and have been cruising the 'search' features of the fora I used to inhabit.

Extravoice; you are very lucky - you have found a one-in-a-hundred-thousand oddity. What you are describing is a splice - the joining of an almost-used roll of paper into a new roll. You see; web printing has one drawback: it runs on rolls of paper and obviously; when a roll runs out, a press has to be able to switch to a new roll quickly. Since the early 50's' there have been methods to splice (connect) a new roll into a used one on the fly. There are two main methods. First is the Flying Paster; the most common of modern Rollstands. The new roll is spun by belts (external) or electric motors (internal) until the surface (i.e. the first layer of paper) reaches the speed of the Running Roll - usually about 100kms./hr. At the right time, a sponge roller drops down onto the new roll and a knife fires right behind it, severing the old roll. The leading edge of the new roll has tape and a carefully-trimmed edge, so it sticks to the old roll and is pulled into the press - if everything goes well - as though nothing had happened. The Rollman (me) can then pull off the old core and load a new roll - it usually take 30 minutes to rip through a 60km. roll of paper. The old style is the Festoon Splicer - the type that has held sway since the 1800's. The Flying Paster spins the new roll; the Festoon Splicer doesn't - it simply presses the taped edge of the new roll to the old one. What makes this strategy work is that the web (the long sheet of paper) passes through 26 rollers in the Rollstand attached to a device called a 'Dancer'. The Dancer is a heavy (600kg.) frame of steel holding half of the rollers in the Rollstand. The Dancer reacts to a piston which maintains a given pneumatic pressure (regular running tension is 35psi.). As tensions in the roll change; the Dancer moves to compensate. It's quite beautiful; the way this huge steel frame moves gracefully up and down in its track to accomodate the roll. When the time of splice nears, the Rollman (me) adds air pressure to the Dancer; causing it to climb to the top of its track. Once it arrives at the top, there is more than a hundred meters of paper between the Rollstand and the Infeed; the press's first unit, less than six feet away. (The lines of paper passing over the rollers are called 'festoons' - spare web used to give time for the splice.) Just before the old roll is used up, I press the 'splice' button, the running roll stops and the festoons drop, using up all that extra paper to give the new roll time to splice in. The splice roller drops, pressing the tape of the new roll to the old one. While the Dancer drops, using up the reserve of paper, the new roll quickly spins up to press speed and the Dancer resumes its position.
As a Journeyman Rollman; I'm accomplished at both Flying Pasters and Festoon Splicers. Flying pasters are far more efficient and require less training to operate. Festoon splicers require an artist's hand. They're fully manual; there are no computers to help. But there is real satisfaction and joy at watching a festoon splice run through. Flying pasters are easy - Festoons are fun! :D
I'm sure you've long given up on looking for an answer to such an idle question, but I love talking about my job. I hope I've educated you - if I haven't; I can at least hope I've entertained you. :lol:
Cheers!

EDIT: I looked on Youtube and found an example of a Flying Paster in operation. http://www.youtube.com/watch?v=mDNyYK8wNWk This is a modern machine; much more advanced than the crummy TEC rollstands I use; but the principle is the same. Watch as the Rollstand spins the new roll up to 80 miles an hour and the Splice Arm drops. There is a black tab on the roll, telling the machine just where the top spire (leading edge) is. When the new roll's surface speed matches the running roll; the effective speed of splice is zero, so while it's loud and looks impressive, the actual stress of the splice is almost zero (assuming the Rollman prepared a good splice.) The actual splice happens so fast you won't see it, but the large cream roller on the arm is the Sponge Roller; the Knife is just below it. You should be pleased, Extravoice. Splices happen once in (on average) 60,000 impressions and are usually collected and thrown out by the Colour Crew of a web-press, three hundred feet (or 4 seconds) ahead. If you found a splice, it means you found a very rare mistake. Either the Colour Crew missed it or (more likely) they were arguing about sports or girls or organizing a coffee run and totally missed the sirens and flashing lights. ;D

Extravoice
2013-Jan-20, 03:29 PM
Thanks for the reply Staiduk. Your response was both educational and entertaining. :)

publiusr
2013-Jan-20, 07:51 PM
I'm just hoping newspapers continue to have a future. I wonder if these machines may have a different use in the future--multilayer membranes and such. Be a shame to see all that covered in dust.

HenrikOlsen
2013-Jan-20, 09:42 PM
I'm just hoping newspapers continue to have a future. I wonder if these machines may have a different use in the future--multilayer membranes and such. Be a shame to see all that covered in dust.
Solar cells. They're getting close to the point where all layers can be applied in a roll-to-roll press.
Doesn't matter so much if their efficiency is less than perfect if they can be produced in square-mile-a-day quantities at penny-per-square-foot prizes.

Staiduk
2013-Jan-20, 09:59 PM
Well let's be honest; my trade is dying. I see the decline and stagnation of the industry; print has had its day. Our largest press is a Directory machine (Yellow Pages) and now lies idle; it hasn't started in six months. The Edmonton Journal is closing its pressroom in December, turning the job over to St. Albert. My plant - assuming it stays open that long - has perhaps 6-7 years of life left; I can't see it surviving for much longer. There'll always be a need for print, but much smaller than in the past; the big plants and giant machines are quickly becoming dinosaurs and are facing the same fate.

Trebuchet
2013-Jan-20, 10:44 PM
As a mechanical engineer, I hate seeing awesome old machinery lik that fall idle. It makes me sad.

The roll changing process sounds much like one I saw in a paper mill years ago at the output end of a fourdrinier machine. Only in reverse!

Staiduk
2013-Feb-14, 10:22 AM
Extravoice:
OK; I know this is old, completely unimportant and has nothing to do with your question but I'd totally forgotten that I'd uploaded a video of my press about 4-5 years ago. I'll use any excuse at all to show off my work, so here's the video. Like I said it has nothing to do with your question but it does show some of the complexity and machinery required to make that simple flyer you toss into the trash or line the gerbil cage with. It also shows Brad - my boss and close friend at work; we've been together (barring a few months here and there when I was posted to other presses) since I started.
I took this video on a lazy Saturday night at around 4 in the morning. I was dead-tired; I'd only been web-printing about a month and was still a Colourman at the time - the union hadn't grieved and reassigned my status yet. As a result my terminology is a little shaky; I understand colour implicitly but was a bit uncertain regarding the web. Still; you'll get a good idea of what web printing looks like. :) The video's here (http://www.youtube.com/watch?v=Th7vpptECuU).

Cheers!

HenrikOlsen
2013-Feb-14, 10:58 AM
That paper looks like it will make a very nasty cut if you're stupid enough to touch the edge.

One question though, it looks like the full width is cut into four which are stacked and folded, but the end result looks like it has more than 16 pages, how's that done?
Are they printed interleaved so they can be stacked after cutting?

Staiduk
2013-Feb-14, 11:55 AM
Math will answer the question for you, Henrik. :D Each individual sheet provides 4 pages - the first and last; and their inside opposites. (In this case, pages 1 and 16, and 2 and 15 inside.)

4 ribbons provide 16 pages. If we wish more; we add more ribbons. A web can technically provide 6 ribbons, though I've never seen a single web provide more than 5. If we want to provide a lot more pages, we can set the folder to 'Collect' mode.

You see; each printing unit mounts 1 printing plate which has two of the same image. Therefore, each impression produces 2 copies of the desired book. If, however, we want to produce a thicker book, we can make plates that have one complete image with twice the number of pages, you follow?

When we do that, we set the folder - that's the part of the press which cuts and folds the sheets into a book - to 'collect' mode. 'Straight' mode takes each copy; cuts it and folds it and releases it to the conveyor. 'Collect' mode cuts each copy, but does not release it. It sends it around and folds it into the center of the next copy in line. As a result; where we had a 16-page book, we now have a 32-page book. I hope that's a clear enough explanation; it's far easier to understand when you're actually watching it.

My mighty Harris 966 is quite impressive - running 'collect' it can run up to a 48-page book. But our gigantic 3-tower Goss U-70 is the King of Collect printing - it's a Directory press; designed specifically for the Yellow Pages and other similar huge works. Each form it runs is up to 96 pages thick. The U-Boat (as we call it) is basically three 4-colour presses standing on their end; it can take massive amounts of paper and turn them into books as thick as a pencil. Sadly, it hasn't run in 6 months so I can't offer a demonstration - all the Yellow Pages went south to the United States.

And yes - touching the edge of an iron-hard web of paper tensioned to 250 pounds and moving at 90 mph. can cause one helluva paper cut. We do, however, regularly touch and caress the running web at full speed. Web tension is a subtle art; every drive point on the 400-ft. journey of the web through the press must pull at exactly the same tension or the finished copy will be less than perfect. We feel the web with our fingers; adjusting chill speeds; nip tensions; RTF and Harmonic balances until the web moves freely. We have to touch the web to feel the tension - we have instruments; but no instrument is so finely tuned as Human fingertips. High-speed paper cuts are a way of life in this business. Web printers learn to scream in terror at the sight of lemon juice. :D

Cheers!

Edit: There's another way you can add more pages; but I was very tired and a little drunk when I responded, Henrik - I'd forgotten it until I'd pressed the 'post' button. Odd since it's the usual method; but alcohol does that sometimes.
OK - we regularly run 24-page flyers. How do we do that? Look at it this way:
Take 3 sheets of paper and lay them on top of one another. You now have 12 pages - each sheet (or 'ribbon') providing 4 pages. OK so far?
Now look at the video at 2:55. See the former board? It folds the sheets lengthwise; a slitter 10 feet up has already cut them. We has 12 pages; we now have 24 - each sheet had held 8 separate images, instead of 4.
Geez - I know that's hard to follow; it's far easier to see if you're watching it in real life and I know I'm not very good at verbal (literal?) descriptions. Suffice it to say the true value of web printing is its versatility - what we can do is limited only by the Pressman's (Brad) and the Rollman's (me) ingenuity at being able to assemble the front end to accept whatever weird format the prepress department comes up with. We run everything from 8-page to 32-page; popups; foldovers; laps; French Doors; Ploughs and Dinkies. Most presses can do one or two variants; we can run anything, given enough time and coffee to figure it out.

Cheers! :D

LookingSkyward
2013-Feb-14, 12:27 PM
Actuall, Staiduk, I think that was a great description, thanks!

HenrikOlsen
2013-Feb-14, 03:57 PM
I think it was my description that was lacking as this was pretty much what I had imagined.
I'm coming into this from an interest book binding, so many parts of the process is familiar, I was looking for confirmation that it essentially works as I would have solved the problem.

Staiduk
2013-Feb-15, 03:53 AM
Yeah - you know what? I really shouldn't post when I'm so tired; that was one jangled explanation. :rolleyes: After 5 years I'm very good at manipulating the web but I don't really think naturally in those terms yet - I'm still a sheetfed man at heart. I shouldn't have added the 'math' crack either; it's been bugging me all day - as some may know here; I'm the very last person that should resort to math on this forum. :) Oh well - at least you haven't asked me to explain a twinned pantleg run yet; I'm still trying to bang my head around that bizarre layout (even after setting it up hundreds of times. I still find myself in the middle of the floor pointing fingers and saying 'OK it's going to go there...then there...get trimmed here...turn here...uh...so it'll be pointing where? Uh...') :D

That's actually why I like working with my friend Brad so much; he's a master at configuration - he can keep an entire 48-page book in his head; see it assembled in his mind long before we even run paper through the machine. Superb spatial awareness, if that's the right term.

Must go; bed calls. Cheers! :)

HenrikOlsen
2013-Feb-15, 04:32 AM
I have to admit the math crack did bother me a bit, as I'd already gotten 16 pages from 4 ribbons and was interested in how you get to 32, still with 4 ribbons.
Oh, how much easier it is to ask the questions when you know a tiny bit of the jargon.
Anyway, apology accepted and thanks again for introducing us to your world. Wanting to know how it works is the natural reaction of an engineer seeing a gorgeous new (to them) piece of machinery.
I'm guessing you could still look at a sheet about to be folded to a 32 page signature (the bookbinding term, I know), and tell where each page will turn up in the result.
Btw, is that the same thing you called a "book"?

Staiduk
2013-Feb-16, 04:10 AM
Yeah, sorry about that Henrik. :) I'd meant no disrespect at all; I have to remember that my intent is not often properly communicated in text. Thanks so much for your questions; as you no doubt noticed I'm very proud of my trade and will talk anyone's ear off all day about it. I suppose I'm lucky - after 20 years in this business I still have the eagerness and delight a newcomer has. My body doesn't neccessarily agree; it doesn't particularly like running and jumping around large, hard and occasionally pointy iron and my joints let me know their displeasure every morning. But that's what Aspirin's for - listening to this giant machine scream as she accellerates to run speed is still a thrill; no matter how many thousands of times I experience it.

Bedtime!
(after a couple levels of Portal 2, of course. ;) )
Cheers!

publiusr
2013-Feb-16, 06:29 PM
I hope your craft stays alive.

JohnD
2013-Feb-17, 04:54 PM
Thnak you, Staiduk! I love learning a little about another man's trade.

I found a video of a festoon splicer in action:
http://www.youtube.com/watch?v=TAUrKdnwWm0
It's printing labels, but I think the principles are the same.

John

Staiduk
2013-Feb-18, 12:25 AM
Well...you're right John; the physics are clearly the same but the mechanism is very different. Ten times larger, for a start. The sliding frame on the bottom of your video is clearly the dancer; mechanically it's not much different from my machine - except in size. The Dancer on our M-300 is more than 1000 Kg. in weight; a frame holding 26 heavy rollers. When the Dancer is fully raised; there is more than a hundred meters of paper for the press to use before the new roll spins to press speed. We're coming into a night-shift period; our crew is about to spend nine days working nights. If the M-300 is running during that period; I'll see if I can smuggle my camera into work so I can capture the 300 in operation. :)

Cheers!

ToSeek
2013-Feb-19, 04:56 PM
As a mechanical engineer, I hate seeing awesome old machinery lik that fall idle. It makes me sad.

The roll changing process sounds much like one I saw in a paper mill years ago at the output end of a fourdrinier machine. Only in reverse!

Back in 1999, the Washington Post built a whole new printing plant in College Park near us, with a $230 million coterie of eight printing presses that seemed as long as a football field. (They had an open house that we attended.) They closed the facility in 2009 because it became surplus capacity. They sold the building to the university and sold the machines to someone but did not reveal the buyer.