Learning Center | IMPACK

How Do Understack Shingles Affect Your Choice of a Packing System?

Written by Maxime Jacques | November 5, 2021

So, you’re thinking of adding a packer or stacker to your folder-gluer.

After reaching out to an IMPACK Expert, you may have been asked whether you run some of your boxes understack.

You’re wondering:

“Why is IMPACK asking me this?”

“How does this affect my packing process?”

“And will this affect my options of a packing system?!”

As an Area Sales Manager and an IMPACK Expert for over 8 years, this is one of the first questions that my team, and I, ask box manufacturers when they produce 4-corner boxes.

“Why?”

The answer is simple: Understack shingles have a great influence on your options of packing systems, the packing speeds you can reach, and the productivity gains you can achieve.

If you process understack shingles, it can change everything around your choice of a packing system.

And, when I say “packing system,” I am referring to any machine that you're thinking of adding after your folder-gluer. This includes packers, stackers, and pre-packers.

In the article What is an Understack Shingle & How Does it Affect My Packing Process?,” I defined what an understack shingle is, the difference between overstack and understack shingles, and why it matters to your packing process. 

If you haven’t read that article yet, it is super important to know before reading this one!

Because this is such an important topic, and a highly asked question, this article will explain how an understack shingle affects your choice of a packing system. 

Plus, to save you time from me explaining this to you in our next meeting, I’ll answer our most frequently asked questions so that you have all the information you need to know regarding your options of packing systems and what to expect.

What is an Understack Shingle?

An overstack shingle on the exit of the folder-gluer’s delivery belt.

An understack shingle is a shingle where the folder-gluer’s trombone stacks each next box under the previous one. Hence the name “understack.” This is shown in the image below:

Understack shingle: Each box is stacked under the previous one.

99% of the time, your operator will set the folder-gluer to produce overstack shingles regardless of the type of boxes being processed. 

This is because overstack shingles are the standard.

Overstack shingles are always the standard choice since they are a little easier and faster to set up than understack shingles.

For some 4 corner boxes, however, the operator has no choice but to set the folder-gluer to produce understack shingles.

“But why?”

Let’s take a look at when an understack shingle is used and why it is used.

🔍 Related: Confused on what is an understack shingle? Discover here “What is an Understack Shingle & How Does it Affect Your Packing Process?

When is an Understack Shingle Used & Why?

An understack shingle is used when you need to process some 4 corner boxes.

In those specific cases, if you do not set your folder-gluer to produce understack shingles, you will end up with boxes interlocking together and crashing against each other.

To understand why an operator must switch to understack shingles when processing some 4 corner boxes, you have to understand the dynamics of the shingle formation.

I will attempt to explain this in the simplest way possible:

At the entry of the folder-gluer’s delivery belt, the folder-gluer’s trombone deposits the boxes one by one, and offsets them a few millimeters from each preceding one, thus forming a shingle. 

This is displayed in the image below:

The folder-gluer’s trombone deposits the boxes one by one forming a shingle. 
Source: Brausse Group. ETERNA TA SERIES II Automatic Folder Gluers. Trombone Section.

The easiest way for you to understand this process is to watch the video below:

 

If for some reason the previous box on the delivery belt offers a catch point, this will not allow the new box to position itself correctly on the forming shingle which results in a crash.

And this is exactly what happens with some 4 corner boxes: They crash.

Depending on the rigidity of the carton, the size of the flaps, and the resulting spring effect, the front flap may open sufficiently enough to cause a hooking point.

This hooking point will not allow the new box to position itself correctly on the forming shingle which will result in a crash.

Granted, the operator can make some adjustments to try to control and limit this from happening.

However, in some cases, the operator will have no choice but to generate an understack shingle instead.

How Do Understack Shingles Affect My Choice of a Packing System?

If you run some of your boxes understack, this will have a great influence on your options of a packing system.

As we have seen, the standard is an overstack shingle which is used for 99% of the boxes.

All folder-gluer packaging equipment on the market (whether offered by IMPACK or any other supplier) are designed for overstack shingles.

Can Packing Systems Process Understack Shingles? 

The answer is no; packing and pre-packing systems cannot process understack shingles. 

We have seen packers, stackers, and pre-packers in all the shapes, sizes, and levels of automation that they come in.

And no matter what technology is used whether Right Angle Transfer Conveyors, Helicoidal Turners, Automatic packers, or Collecting Tables, no packing system can handle understack shingles.

Whether you have:

None of these packing systems can handle understack shingles. 

That’s just the reality. But, there is an exception.

I’ll get to that in a few seconds!

Why Can’t You Process My Boxes with an Understack Shingle?

We cannot process understack shingles simply because packing systems are designed and built to process overstack shingles. 

Whether IMPACK or any other supplier, no packing system on the market that can handle understack shingles.

Are there Any Exceptions?

The answer is yes; there is one single exception.

IMPACK’s Ergosa C packer is the only packing system in the world that can handle understack shingles. And without any extra cost.

Its unique design and new original packing methodology allows you to pack your boxes from an understack shingle provided that the boxes do not need to be turned/inverted.

That is, one of the packing modes of the Ergosa C, the Vertical Mode, is specifically designed for 4 corner boxes. 

IMPACK’s Ergosa C in Vertical Mode with the PerPack Module.

The Ergosa C’s Vertical Mode allows you to process understack shingles without any additional customizations, without any extra costs, and without requiring you to turn or invert your boxes.

🔍 Related: Curious to learn about IMPACK’s Ergosa packer and the packing modes it offers? Check out What are the Ergosa Packer’s 3 Main Packing Modes & What Benefits Do they Offer to My Packing Process?

Is it Possible to Customize a Packing System to Process Understack Shingles?

Unfortunately, the answer is no. 

It is not possible to customize an IMPACK packing system, or a non-IMPACK packing system, to process understack shingles.

But, there are 2 exceptions to this:

  1. IMPACK's INTRO.

  2. Collecting tables

IMPACK’s INTRO and the traditional Collecting Tables, such as Bobst’s Handypack GT or IMPACK’s Packing Help Stations can be customized to process understack shingles.

That said, if you were to customize IMPACK’s INTRO or any Collecting Table to process understack shingles, they will no longer be able to produce overstack shingles.

And quite frankly, in the last 10 years, I have never seen a client with a sufficient percentage of understack shingles that would justify an investment in this kind of customization.

It is just not a smart investment.

Besides those two limited exceptions, no packer, stacker, or pre-packer can be customized to process understack shingles.

What Are My Options if I Process Understack Shingles?

So, you process an understack shingle, now what?

If you’re one of those people who skip straight to the end, here are the most important takeaways:

  1. Remember that there are two types of shingles: Overstack shingles and understack shingles. 99% of the time, your operator will set the folder-gluer to produce overstack shingles since they are the standard choice.

  2. Understack shingles are used when you have some 4 corner boxes that cannot be processed with an overstack shingle.

  3. If you have a large percentage of 4 corner boxes that require an understack shingle, this would change your choice of a packing system.

  4. There is no packer, stacker, or pre-packer on the market that can process understack shingles. All packing systems are built and designed for overstack shingles and they cannot be customized to run understack shingles.

  5. If you need to process understack shingles, you have only 2 options:

    • You can request to customize IMPACK’s INTRO or a traditional Collecting Table such as Bobst’s Handypack GT or IMPACK’s Packing Help Stations. Note: If you customize any of those machines to process understack shingles, you will no longer be able to process overstack shingles on them. In addition, it would require substantial investment and could become very expensive fairly quickly. 

    • Consider IMPACK’s Ergosa C packer. IMPACK’s Ergosa C packer offers a packing mode called the Vertical Mode. The Ergosa C’s Vertical Mode is the only packing system in the world that will allow you to process understack shingles without any additional customizations, without any extra costs, and without requiring you to turn or invert your boxes.

Your Next Steps:

👉  What are the Ergosa 3 Main Modes & What Mode is Best for What Box?

👉 What is the Ergosa C’s Vertical Mode and What Production is it Best Suited For?

👉 How to Maximize Your Productivity with the Ergosa C's Vertical Mode.