ZeroPak Vacuum Sealer Forum Deal

[zeropak]

Do you ever use bags from other places eg Facebook marketplace etc?

That's waking up a fairly old thread. Not sure if this question is directed at me and I guess I could be accused of Bias towards my own brand. However this seems like a good opportunity to offer up some considerations when choosing vacuum film.
The composition of vacuum film can vary considerable between brands, There are 2 main ways to manufacture vacuum film cheaper, Make it thinner or make it out of cheaper raw material. Thinner film is not always a bad thing, however the cheaper raw material will generally cause 2 main issues. Firstly there is this thing we cause premature sealing, this is where the residual heat in the seal bar (after doing a few bags) compresses the internal embossing and shutting off the air extraction before the vacuum process is completed. The second is unreliable seals which normally shows up as a rough looking seal line because the bag material has distorted under heat. This can lead to seal failure and vacuum release later.
On the subject of bag thickness, it can be a mistake to choose film based just on thickness, there are 2 main things to consider, hardness (toughness) and thickness. A thick soft bag can be inferior compared to a harder thinner bag. For example we recently tested some Korean film which was around 130 micron thick but it was so soft that the bags started to seal prematurely after sealing a half dozen bags.
The other major issue we commonly see with some brands is the embossing, some film is embossed by using a stamping process which means the embossing is evident on the inner and outer surface of the bag, the reason this is not a good thing is that the external embossing can create an air leak between the bag surface and the neoprene chamber seal, this will result in the machine appearing to pull a decent vacuum on the bag but it will not switch on the seal function. This seal function is activated by a pressure switch inside the machine, there needs to be full or virtually full vacuum to activate this switch. We say that the embossing should be on the inside of the bag only.
Then finally on the subject of embossing patterns. The ideal pattern will be dimples or diamonds of some description, this type of pattern allow air inside the bag to flow in 360 degrees this tends to minimise the potential for air locks. The other common pattern is lines with do have a much larger potential for leaving air locks inside the bags.
Well that covers most of the major considerations, any questions please ask.