Reddit reviews 217 Silicone O-Ring, 70A Durometer, Red, 1-3/16" ID, 1-7/16" OD, 1/8" Width (Pack of 25)
We found 2 Reddit comments about 217 Silicone O-Ring, 70A Durometer, Red, 1-3/16" ID, 1-7/16" OD, 1/8" Width (Pack of 25). Here are the top ones, ranked by their Reddit score.
Made of silicone for use with a variety of chemicals and fluidsCan be used across a wide temperature range from -65 degrees F (-54 degrees C) to 450 degrees F (232 degrees C)Round in cross-section to provide a seal between cylindrical overlapping surfacesDurometer (hardness) of 70A for resistance to penetrationMeets standards defined by Aerospace Standard AS568A
For the main plunger and pusher seal I use 217 sized Silicone O rings. You can get them right here off amazon.
The O ring seat I use is currently just a flat surface. I've experimented with floating seals and a sloped seat but really noticed no difference. The actual diameter of the O ring seat is highly variable, because of the high variation in the old Poly tube I had to individually tune each blaster's seat. The usual range of diameters was between 1.22" and 1.24".
For the prototype Alloy tube (Which actually has a slightly larger ID of 1.509") I've currently worked the O ring seat to a diameter of 1.232", and even at that I believe I can go a few thou smaller while maintaining a perfect seal. I'm hoping that once the alloy PT becomes production ready, because of it's greater consistency individual seal tuning for each blaster will be a thing of the past.
http://www.amazon.com/gp/aw/d/B000FMYSEM/ref=mp_s_a_1_1?qid=1396656521&sr=1-1%CF%80=SX200_QL40