Anyone know what material pneumatic o-rings are made of. Rubber obviously; but there are many different types of rubber. I want to repair some of my air tools but $25 is way too much money for a "seal kit" when I know I can buy a multi-assortment kit for that price from an industrial supplier and fix 5 of my guns in one shot. I just don't know what type of material the rubber is. EPDM, Buna-N, neoprene, hard PTFE, etc...
Most O-rings which are black in color are made from a material known as "Buna-N". This is the basic O-ring used in millions of applications. These are fine in most air tools. The key to these is not to allow too much moisture to get to them, nor should you lube them with something like WD-40 or vaseline. There are better O-rings out there, with "Viton" being a much better O-ring for power tool usage. The EPDM O-rings are good also. The viton rings are generally a light greenish color and are made of a different synthetic rubber compound with some silicone added. These will stand up to a lot of different lubes and chemicals. Believe it or not, it would be worth your time to remove the O-rings you want to replace and go find a business which deals with O-rings, such as "Bearings & Drives", "Fastenal", or a local hydraulic repair shop.
The Following User Says Thank You to Thurman For This Useful Post: