Mylar Bags folding problem

Yakster

I’ve been using 7 mil Mylar bags from topmylar.com for pipe tobacco storage in addition to some small canning jars for my open stock. I think they work well, weigh less, and take up less space, but they come shipped flat and warn against folding the bags.

Ken Byron ships his blends in Mylar too, but folds the bags for shipment. I just noticed four pinholes in my bag of Burley Morning Pipe this morning where the bag has been folded. You may want to check your KBV bags and if there’s a problem move the tobacco to jars or new bags.

IndustMech

@Yakster. Does the bag leak air as well as light?

Yakster

Not sure, I already cut it up to take the label off to put it on the new bag. Maybe I'll fish it out of the trash later and check.

Yakster

I tried poking a toothpick through and also tried to see if water would weep out and it looks like the hole may not have made it all the way through, but at least several layers are missing at the stress point. Something to watch out for.

0patience

Mylar doesn't like being folded.
It is more or less a directional structure.

Mylar - Biaxially-oriented polyethylene terephthalate
Most polyethylene doesn't like being bent, but biaxially oriented especially don't care for it. It has a tendancy to fracture.

Sorry, probably more than you wanted to know.

Stubble

Chris, was this bag as shipped from KBV, or have you been unfolding, opening and closing, and then re-folding?

Yakster

I've been unfolding, opening, closing, and re-folding.

Stubble

Thanks @Yakster

jsnake

Because of potential issues I jar all of mine within a few days of receiving a bag. I just bought 2 cases of jars which really aren't that expensive and just jar and sticker them. I lost an expensive tin of McClelland due to a small dent behind the label that eventually led to an unseen hole. It was heartbreaking because the tobacco was dust inside. Any dents or bags and I jar them.

Yakster

I use a combination of storing tobacco in tins, canning jars, and Mylar bags. Lately I've been playing with re-sealing open tins with my food saver in a vacuum canister. If you clean the lid of any loose tobacco and make sure that the sides aren't bent from opening, I find that I can get a good seal on rectangular tins which seem to be more likely to have issues than the round tins. This might be prudent even for tins you haven't opened yet but may not have a strong vacuum seal. I had tried storing my tins whole in Mylar bags but find that this sealed environment can lead to the tins rusting from the outside in which isn't good, so either reseal the tin or transfer the tobacco to a canning jar or a Mylar bag.

Amos_Umwhat

Interesting solution. I like that you preserve the tin. I find that I can't keep tins, the tobacco always dries out. My solution has simply been Mason Jars, and I painstakingly peel the label and put as much of it as is recognizable onto the flap of the jar. This works well, but I loose the original tin and I miss the connection with the history. Just aesthetics, I'm much better off with the jars, but still, nostalgia.