Folding and Grain...

[kdw75]

We run about 30% of our volume on 100# Dull Text. If we try to crease and fold parallel to the grain it cracks and even splits sometimes, but if we crease and fold perpendicular to the grain, it looks beautiful.

I was reading a website the other day about grain and it was saying just the opposite and that you should fold WITH the grain.

Can anyone shed any light on this? Unless all the skids we get are mis-marked, I don't understand why this is.

 

[gordo]

Have you checked the grain direction yourself rather than relying on the label info?

 

[kdw75]

I just checked it by rolling and checking resistance and wetting to see which way it curls. The grain is as stated.

 

[Magnus59]

Is this digital print on a toner based machine?
The heat applied to the stock during printing dries out the paper making it more susceptible to cracking, especially with toner which cures on the surface of the paper.
I can't be sure from the photo, but it looks as if the score/crease is on the inside of the fold, it should be on the outside of the fold otherwise you are applying more tension to the paper fibres instead of less. The purpose of a score is to change a 180° fold into two 90° folds to reduce the tension on the fibres and to do this must be on the outside of the fold.

 

[kdw75]

Is this digital print on a toner based machine?
The heat applied to the stock during printing dries out the paper making it more susceptible to cracking, especially with toner which cures on the surface of the paper.
I can't be sure from the photo, but it looks as if the score/crease is on the inside of the fold, it should be on the outside of the fold otherwise you are applying more tension to the paper fibres instead of less. The purpose of a score is to change a 180° fold into two 90° folds to reduce the tension on the fibres and to do this must be on the outside of the fold.

Yes, we ran this on a toner machine. We tried creasing this both sides using creasing matrix on letterpress. We even tried creasing from front and back. That still provided a fold that looked worse than a non-creased fold against the grain.

 

[pippip]

Something definitely isn't right?

We have always creased and folded with the grain. If you're perfect binding you could run into all sorts of problems. Folding an unprinted sheet by hand is generally enough to confirm the grain direction. We use a Morgana Autocreaser and never have a problem no matter what way the grain or toner coverage is or which side is up.

You running the sheets straight out of the packet? Nobody's cutting down sheets i.e. converting LG to SG?

 

[scotts]

Don't forget the tear test to find the grain too.

We use a Morgana Digifolder on digital jobs, and some offset jobs. It makes a wider, more gentler crease for the fold.

 

[kdw75]

Tear test confirms the grain is correct. We have for years been running brochures and always been creasing and folding against the grain with fantastic results. We only have problems when we crease and fold with the grain. The outside layer just splits completely through. On cover stock it oddly enough works just the opposite and we always have the best luck creasing and folding with the grain.

 

[PricelineNegotiator]

I always reference a sheet as 12 x 18" or 13 x 19", but on the label it can be printed as 18 x 12" or 19 x 13". The grain direction is the last number listed on the label. Text weights are grain long and cover sheets are grain short. Are you taking this into account when you are talking about true grain direction?

 

[kdw75]

Yeah. I have double and triple checked the grain.

 

[PricelineNegotiator]

What is the brand of the paper? Have you tried calling the mill to see what they think?

 

[jotterpinky]

Kdw75, I’ll second your results. We have seen the same thing for years and always run our coated text stocks this way. We also run the crease inside the fold as the finished product looks better.

 

[bill kahny]

Please tells us what brand of paper and where you are buying it, I run a lot of 100 dull coat text.

 

[namelessentity]

If this is digital then I'm not surprised at all. It sounds to me like you're using finishing equipment designed for traditional print and not digital.
A score and a crease aren't the same thing. If you use something designed for digital print you should be able to fold clean no matter the grain direction.

Why is Creasing (or Scoring) Paper Important?

Why is creasing paper important to your printing operation and how can you get the results you need?

www.technifoldusa.com

 

[jotterpinky]

We’re running Titan paper by Hansol. It’s offset stock - trim and run on our digital too. We’re using a Duplo 745 and Morgana autocreaser, same results on both. We also on a rare occasion run this through our Heidelberg Cylinder letterpress we use for die-cutting and scoring. (No digital prints just offset prints) and we have similar results. - must be brand related

 

[kdw75]

We are running Polar Bear branded papers

We have tried creasing using matrix on our Heidelberg Cylinder as well as the Tri-Creasers on our MBO folder. Against the grain works best in both cases.

 

[davarino]

Here's your answer: your problem is twofold.

The thinner the paper, the lighter the score you must make. (Not "less wide", but less impression.) Remember that generally you are breaking the paper fibers somewhat when you score (or crease), even if it looks as if you are simply compressing them or re-forming them.

A sheet that has been baked in a digital machine will be more brittle and won't be very supple until it has absorbed some moisture. And even then it won't approach the suppleness of a sheet that never was baked.

So: Try to let the sheets re-humidify a bit and use the broadest score you can get away with, with the least pressure. If you can channel score to give 2 "hinges", do it.

As a general rule: 100# gloss book and lighter simply needs a nice, loose fold along the grain without any score at all. If you want a tight fold, that's where you'll get your problems.

 

[Craig]

Have you tried a different brand of paper. We had the same thing happen when we changed from one brand to the next. We score everything with Tri-Creasers and that had little effect. Changed to a different brand and back to normal.

 

[Barrybw]

Craig, I'm always trying to improve my final product. Will you pass on the stock that seems to work for you. Thanks!

 

[namelessentity]

I'm not Craig, but our shop orders Topkote from Spicer's and it's never given us issues.