Diagonal wrinkles = something is crooked (roller diameter, roller alignment, roller hardness, material)

Glad it was helpful!

The best way for an initial contact is to email a problem description including defect photos and/or web path diagram or whatever else might help describe the issue. I am at [email protected].

The roller book is the only one on that subject. However, The Web Handling Handbook, Destech 2020, has a great chapter on the subject AND is the Bible of web handling.

@@DavidRoisum Ok, thanks.

You bet!

I'm not entirely sure I understand the question. A drive motor connected to any rigid body, such as a roller, will not have any CD profile (ie., variation across the width)

My experience with builders is that few, whether salespeople or service engineers, are great problem solvers. They can also act defensively to protect their own interests rather than those of their customers (you and your web). What they can do is to advise how to bring the machine into 'like new' condition. Still, if you have a problem with a new or like new machine, then you are mostly on your own to figure things out.

I am happy that this served your needs. Let me know if you have any topics you would like to hear about!

@@DavidRoisum I purchased ur book “The web handling handbook” and I did make carbon idle rollers with very low drag and low mass for converting machine. I am researching grooved rollers for web spreading purpose. Can u pls share how to design suitable groove for NW and PE film

@@angchitinh5155 A starting point design for grooving is given on the Air Lubrication Calculator, by (Steven) AbbottApp. It is based on the heuristic given in my 1996 Mechanics of Rollers book which has been vetted by Dr Ron Swanson of 3M and others. Cross hatching is best for thin films (to avoid wrinkling), no matter the width, depth and pitch of the grooving required for air handling.

@@DavidRoisum sounds good, I intended to buy also “Mechanics of roller” which you mentioned, but it is not a PDF file as “The web handling handbook”. So I still pending. Anyway, I will buy the book

The publisher, Destech, offers an E-book as a key/password to a webpage/site. Few book publishers will ever use PDF because of the risk of copying.

Thank you for the kind words Jake. Let me know if you have any topics you would like to hear about.

Good question Michelle. There is very little published work on winder vibration, much less the paper additives to moderate such behavior. However, I can say that just a couple of pounds per ton of friction modifiers, say soapy additives, can tame a tiger. Some kraft paper mills must use these additives solely to make the paper windable (DFM). I wrote a couple of papers on the mechanics of winder vibration years ago, but your question was not one of machinery, but rather of paper. A very astute query as even the best winder design and maintenance will not tame wild beasts of paper grades with high COF's.

I am a web handler, not a paper expert (even though I've worked in the industry for 45 years). The best source for paper defects is The Ultimate Roll and Web Defect Troubleshooting Guide, TAPPI PRESS, 2013. It has some 500 defects listed, including a whole chapter devoted to paper.

That's great!

Thank you for the response. That is a very reasonable desire. However, demonstrations are extremely time consuming to video and edit, perhaps doubling the already long 3-4 hours of time to make a weekly show. Also, I can not take pictures in clients plants, much less post them. Finally, at least part of the theory is well enough known, but at the beyond Ph.D. level. (Prof Ron Delahousaye, my roomate 35years ago, modeled the easier half of the problem, the concave spreader as his Ph.D. thesis). As such, it wouldn't be useful for the general audience which is the target for this show.

You are so welcome!

Happy to help!

Fast, a few ms, good, to a few 1/1,000, best we got so far

My guess is that it is a wrinkle at a small angle. If so, something is crooked, uneven, different, misaligned ... What could that be? The web and anything that touches the web within 1 meter of the wound roll, including core, layoff roller ... That is a long list.

Thank you for the kind words. Best of luck on your new web machine design. - Dave R

Already done. I have more than 25 shows on the subject. Most are labeled Web201.45a-r.

I have to think about how to do that. Web handling is a science that guides us about which knobs to turn and in what direction for a very specific well-defined problem. Six sigma is a set of tools most useful when science falls short. I did write an opinion piece in the Converting Magazine that ended with 5(s) comes before 6(sigma).

Torque is a machine unit rather than a web unit. Motor torque can be made into a web unit by dividing by roller radius and web width to get tension in customary units.

Textiles is the oldest. Paper is the oldest + largest.

Glad you liked it!

1st step: The Ultimate Roll and Web Troubleshooting Guide lists proper names, aliases, causes and cures of more than 500 defects. Other good sources are my Dave's Defect series on KZbin.

Most welcome!

Glad it was helpful!

Thank you for the kind words. I try to find topics that few have spoken on as subjects.

Thank you. I hope to amuse and educate at the same time when possible.

Same to you!

Yes Joshua, thank you for asking. I should have use the word thickness because it is more neutral and more universal than gage (film, metal) or caliper (paper). This was an especially egregious word choice for me, one who preaches about careful word use.

Thank you for clarifying ​@@DavidRoisum

Great question. Here is the short answer: both ;) The reason is that the Defect book covers a lot more defects (because it also does defects not related to web handling, such as coating) and is quicker to use, but gives no explanations whatsoever. If you want to know how the world works, the Handbook would be the best.

Thank you for the kind words. Let me know if I can help in any other way.

You're most welcome!

Thank you for the kind words. Let me know if there is a topic you would like to hear about.

They are a ton of work to produce, but comments like this are the fuel to keep me going and also helps with search engine ranking. Thank you.

These guidelines are great starting points for most web materials run on most web machines.

Absolutely!

You are so welcome! See the next in the series where the fix is something entirely different. Web301.30c - War Stories - Trim Chute, To Be or Not To Be. kzbin.info/www/bejne/eWPHiWRmiceCprs

AIMCAL's Converting School Online (now R2R) hosts this as video-on-demand. converting.pathwright.com/library/web-handling-and-converting-14135/33081/about/

So true. The trim chutes common on these winders include at least a half dozen independently adjustable compressed air jets. These form an air layer that USUALLY stabilize the web to a small, 1 mm or so, air float height. In this case they did not. A bit of mechanical curvature was needed because straight in didn't go, well, straight in. Air is quite unpredictable.