Folding machines can be purchased from $750 to $35,000 from Sydney Stone with a variety of different features and uses. The starting point for all of these folders is the feeding style; folders either come with a friction feeding system or an air feeding system.

 

As the names dictates one method uses friction and the other uses air to feed the sheets of paper into the folding machine.

The friction feed folder has a feeding mechanism that has one to three rollers across a bar, with a tab below the centre roller. These rollers spin and the sheet of paper is to be pulled into the unit. The tab on the bottom is to hold back a second sheet of paper from entering the folder at the same time as the first, preventing double sheet feeding. Once the sheet of paper enters the folder the fold rollers take over moving the paper through the process of being folded. (for more information on buckle plate folding please read our article on buckle plate folders)

>Two limitations of friction feed folders:

1. Much like a car tire on ice, friction feed folders struggle with feeding coated papers with any consistency, at times you may be able to have the folder on a consistent run with coated paper but certainly there are an equal amount of times when the unit will struggle to feed even a single page of coated paper
2. Static: digitally printed work is printed with a heat and static fusing process. After printing is complete the pile of paper still maintains is static charge and separating sheets can be difficult using a friction feed process. Air feeding better separates the sheets prior to feeding them into the folding unit.

 

Air feed folders use a very different premise than friction feed folders and there are two different types of air feed folders, top feed and bottom feed. Let’s start by describing how bottom feed folders work. The Morgana Major Folder is a great example of a bottom feed folder. When using a bottom fed air feed folder we do three things:

1. Apply air to the pile to float the work on top of the bed of the machine
2. Have a rotary suction drum that pulls air through it in order to suck a sheet of paper to it and then turns to pull the sheet into the folder.
3.  A caliper to limit the amount of paper that can be pulled into the feeder at one time.

 

A top feed system uses a different premise than bottom feed. We use the following three stages when feeding paper using a top fed air feed system. The Duplo DF 100 is an example of a top feed system.

1. Apply air with a fan to separate the top pages
2. A sheet of paper is sucked to a series of tractor belts with a suction fan, and these belts transport the sheet into the fold rollers
3. The caliper system is similar however inversed so we are able to increase or decrease a gap so that only one sheet of paper can travel into the unit at one time.

 

Using these air feeding techniques these folders are able to feed coated papers, statically charged paper and a very wide variety of paper stocks with greater ease than you would have on friction fed units.

 

While friction fed folders are more limited in the variety of papers that they are able to feed and generally operate slower than air fed units, they can also be purchased with a high level of automation, enabling them to be very productive in their given environment. Air feed folders do come at a greater expense than Friction feed units but offer a wider range of paper to be accepted and increased operating speed. Automation is become more readily available on Air Fed Folders with the NEW Morgana DocuFold PRO and Duplo DF 1000 folders. The last category of folding machines is for machines that can crease and fold in one pass, these systems are air fed but incorportate a crease matrix along with a knife folding system to process heavier paper stocks without cracking, marking or having curl on the printed product.