Common o-ring sizes

[+Doc_musketeers]

Our team carries some in-field repair items. We have some o-rings for the nanos and bison-style tubes we use but would love to be ready to repair other sizes as well as a favor to other COs, especially for isolated caches! Can the community chime in about common sizes?

[+cerberus1]

We've seen "bison-styles"  from 5/16", to over 4", so "common" might depend on your caching area.  So many knockoffs now, sizes vary.  At one time I remember this was a simple answer. 

  The few bison-like containers we see these days are aluminum from china I guess, and many don't even seem to have a proper threading on 'em. Most don't have a decent o-ring on them to begin with.   I have a couple assorted O-rings from 1/4" to 1/2" on my camera bag as noise deadeners for my GPSr and stuff on the straps JIC, but haven't found an "isolated" bison in the wild in years.  

We still carry a couple of rubber washer-like gaskets for matchstick holders though, and have seen them vary between 7/8",15/16 and 1" as well.

[+Doc_musketeers]

35 minutes ago, cerberus1 said:

So many knockoffs now, sizes vary.  At one time I remember this was a simple answer. 

That’s what we feared, lol. I guess I’ll get a selection and start figuring out what we have around here. We actually see quite a few bisons in our suburban areas

[+Dominoes]

Harbor Freight sells a 382 piece O ring assortment  for $7.69, that's only 2 cents per O ring.

Edited February 1, 2018 by Dominoes
bad grammar

[+kunarion]

1 hour ago, Dominoes said:

Harbor Freight sells a 382 piece O ring assortment  for $7.69, that's only 2 cents per O ring.

 

I bought a couple of their "assortment" boxes.  I managed to use maybe two sizes from each, and those sizes are all gone now.  The rest don't properly fit any container I've found. Various thicknesses, skipped sizes, it's more like a mix of findings than an organized set.  I mostly used it for my own caches.  Some O-rings I had to stretch a little when installing, which I think is why they break so often.  Some of my caches were match tubes which use flat O-rings, not in any assortment.

But I have the leftovers handy, just in case. 

Edited February 1, 2018 by kunarion

[+colleda]

I have a box of assorted sizes that I bought from Aldi. When replacing an O ring I give it a very light smear of either silicone oil or lanolin grease. This helps to preserve them a little longer than if they were left dry. Vaseline should also work.

[+WarNinjas]

Very cool of you to do! I agree with everyone else that you would just have to buy a variety pack.  I have a drill adapter I use at work that seems to break every few weeks of use.  If I take it apart it has a few good quality O-rings inside of different sizes.  They are usually still in good shape as well.  I take them with me and sometimes will add them.