Digital stock consistency problem

[dagoof]

Was hoping someone could help - I'm a digital printer and have had a large quantity of card stock supplied from a 3rd party. I was provided with samples to test beforehand, which I did and was happy with.
On delivery of the full consignment I've found there are two qualities of stock - they are very similar in most respects, however, one stock is more rigid than the other and will not go through our digital machine.

The supplier insists the stock is the same but, considering paper stocks are made to specification, is there any way it can be or is this lies? If so, is there any way to prove it?
The supplier does some finishing to the stock, so we can't return it and this has the potential to finish us if we can't resolve it

 

[PricelineNegotiator]

Grain direction? If it's a heavy and dense stock and the grain direction is the opposite of normal, digital presses can have issues feeding the sheet.

 

[Possumgal]

My first thought is that the troublesome stock might be from an old batch. Somebody where I work found an old box of stock the same as one we usually use, but it just kept jamming in the digital printer. I put it aside to use on offset. When it gets too old, it just won't go through those digital machines.

 

[pippip]

Try folding the two sheets, if the grain is different then one will have a smoother crease than the other.
Grain direction is so important no matter what weight depending on what the job is, you'd be well within your rights to reject the order based on that.

I'm the same in that some 350gsm will go through our machine and other jump all over the place, you can hear it as it goes through the machine.

 

[wonderings]

Maybe try and get a hold of a paper thickness gauge, you can compare with what feels stiffer to the other stuff. Could be the grain as well, but this is one simple thing to rule out.

 

[dagoof]

Thanks for the replies - I'm just looking at it again under different light...IMO, it's definitely a different stock. Though the color and mic are the same, you can plainly see the calendaring/texture on the two are different. We took it to them and showed them it looks & feels different, problem is, they're denying it and the onus seems to be on us to prove it.

Is there any way to prove that (even though it's self-evident)? They just keep saying "it's the same". I suppose there's 2 scenarios, 1: the supplier knows and is trying to pull a fast one or 2: the mill is supplying inconsistent stock (but I don't know if that's even possible/have my doubts).

 

[akalaray]

Who is the supplier? If it is a company with a good rep they will step up!

 

[MailGuru]

When you order paper, you need to specify the grain direction. In many scenarios, especially, if you don't specify grain direction, in order to get the most out of large sheets, you will get a "swing-cut". For instance, on the larger sheet, they may have two sheets that are being cut out "portrait", and, 1 sheet that is being cut "land-scape" at the bottom. That bottom sheet is called a "swing-cut", and, the grain direction will be perpendicular to the top 2 sheets (top 2 sheets are long grain, bottom sheet is short grain). Since the grain is different, you will definitely notice a difference in rigidity of the paper. Could this be the problem?

-MailGuru

 

[PricelineNegotiator]

When you order paper, you need to specify the grain direction. In many scenarios, especially, if you don't specify grain direction, in order to get the most out of large sheets, you will get a "swing-cut". For instance, on the larger sheet, they may have two sheets that are being cut out "portrait", and, 1 sheet that is being cut "land-scape" at the bottom. That bottom sheet is called a "swing-cut", and, the grain direction will be perpendicular to the top 2 sheets (top 2 sheets are long grain, bottom sheet is short grain). Since the grain is different, you will definitely notice a difference in rigidity of the paper. Could this be the problem?

-MailGuru

This is probably it, and why they are saying "it's the same paper, bro".

 

[Shawnd]

A lot of these "cheap" paper guys will take roll paper or large sheet press paper and cut it down to cut sheet sizes, I have had my share of nightmares dealing with it and now only buy from respected mills. Paper would show up repacked in brown paper boxes and have foot prints on it and dust and even grass from it being dropped on the floor, edges all bent and even forklift holes in the side of the boxes.

These guys will cut up whatever paper they can find cheap, which would change the batches like you see.

Ditched the cheap paper guy in NJ and now I have less headaches.

 

[dagoof]

Thanks for the replies - MailGura, I think 'swing cut' has been it exactly, we've got a mix of grain direction all through the stock which means some of it runs and some of it doesn't. Problem is, it's mixed all through the consignment, the only thing we could do is go through it 30 sheets at a time and see how it feels which is no use at all. I've got a pile of back orders that are already late and it'll be 2 weeks before I can get more stock...these guys have really done a number on us

 

[MailGuru]

Thanks for the replies - MailGura, I think 'swing cut' has been it exactly, we've got a mix of grain direction all through the stock which means some of it runs and some of it doesn't. Problem is, it's mixed all through the consignment, the only thing we could do is go through it 30 sheets at a time and see how it feels which is no use at all. I've got a pile of back orders that are already late and it'll be 2 weeks before I can get more stock...these guys have really done a number on us

Sorry about that, dagoof. I feel your pain. Nothing more frustrating than material that won't run. I wish I knew of a faster way to help you. Make sure you know which gran direction (short or long) is running successfully so you can specify it on your next order.

-MailGuru

 

[old guy]

jog about 100 sheets of each "batch" of paper. turn the stack so that you are looking down at the shorter edge. if you see a smiley or frowny curl that is short grain. if the paper wants to fall over your fingers that is long grain. jogging handfulls and separating the different grains will be easy to see this way. you can get the curls all going one way too.