kwinter
Contributor
I can't believe the timeliness of this, but I actually took Herman's and Awap's advice last night. I wanted to order o-rings for my new rebreather to have in my spares kit, and most were not standard sizes I keep around. Several were metric sizes. One of those was not available in viton from any of my usual sources, and several other metric ones were ungodly expensive. The manual called for using NBR 70 so I ordered Buna o-rings for the first time in years. Something about it just feels wrong, but I have been informing people for years that O2 lube is not necessary anywhere in the RB except the O2 first stage, so I guess nitrile o-rings are fine too. Cost difference was about $20 for the set, not including how much that one metric ring would have cost in viton if it could be found. Then again, the cost to buy a service kit of o-rings from the rebreather supplier would have been over $50 compared to my getting them for less than $10. I think I'll continue to order 90 duro rings in Viton, but I might just switch to Buna for the 70 duro rings next time.
Thanks Herman and Awap.
Thanks Herman and Awap.