It's All About the Hub

The most distinguishing feature of a DVD case is its hub. And avid DVD users know the names of their favorite hubs as well as they know the names of their favorite directors.

Currently, two of the most popular hubs, among our own customers and on various message boards, are the M-Locks and the AlphaPAK hub.

M-Lock Hub	ALPHApak Hub

Both of these hubs come from noted manufacturers who are innovators in their field. In addition, the hubs are known for placing minimal stress on the hub, preventing "floaters," and still allowing easy disc removal.

With the exception of the AlphaPAK, end-users tend to favor push button hubs. Many DVD users report that, when removing a disc from a pluck hub, the disc bends, which makes them nervous.

There are several styles of push-button hubs available. There are four different hub styles available in Polyline's one-disc DVD cases:

DVSR12CB & DVS12CB	DVMPR
DV121C	AMII12B Nexpak's Amaray II

There are times, however, when a push-button hub is not the best choice. For example, in thin or slim-style DVD cases, push button hubs have been known to cause floaters, particularly when the cases are shipped individually. During shipping, if a slim-style DVD case is compressed, it can press down on the hub and release the disc.

With slim style DVD cases, you want a pluck hub. The trick with pluck hubs is to select one that is snug enough to ensure your disc is secure during shipping and handling, but can be removed without fear of cracking or bending the disc. With a good DVD hub, you can feel the disc engage when loading by hand and there may be a "click" sound when the disc is locked into place. You don't want a hub that requires a lot of pressure to engage the disc, because this puts stress on the disc's hub and could cause radial cracks around the center. If you hear a harsh "snap" when hand-loading your disc, the hub is too snug.

Here are some of the lift-up or pluck hubs available in Polyline's one-disc DVD cases:

VPDV1SB PL-Pro	DVRAMP
DVA12DG Nexpak's ALPHApak	DVT12C Nexpak's THINpak case
AM12DG Nexpak's Original Amaray

There is a trick to removing discs easily from lift-up hubs. Place the open DVD case on a table or other flat surface. Use your thumb to press down on the hub while while lifting the disc edge with your forefinger. (The DVRAMP has illustrated directions on the inside of the case.)

A good hub is also made of good materials, so pay attention to the amount of recycled content in your DVD case. Virgin polypropylene is a pliable and forgiving plastic, which is desirable in a pluck hub. The more recycled content the DVD case contains, the more rigid it becomes. At Polyline, our favorite blends, are about 80-percent virgin material to 20-percent recycled. It's a good mix that retains most of the properties of virgin material, while reducing production cost. Unfortunately, it's difficult for manufacturers to keep a consistent ratio of virgin to recycled materials, so they won't guarantee a minimum amount of virgin content. A good mixed-content case will still have a good weight to it and little or no odor. If your case feels extremely light and has a strong smell of burnt rubber, it contains a large percentage of recycled materials and will be brittle.

As a side note, a former hub favorite, Amaray's "ying yang" hub is no longer available. NexPAK is phasing out the old design in favor of a hub that is easier to mold. Currently, the Amaray II case has a push button hub and the Original Amaray has a pluck hub with a Y or peace-sign shaped opening. Both Amaray boxes will eventually sport the peace-sign hub.