Thread: Gas Block
View Single Post
Old 22nd April 2008, 14:01   #1 (permalink)
DanFountain
This is my custom title!
 
DanFountain's Avatar

Current Rebreather/s:
Home Build

Other Rebreather/s:
Home Build
 
Join Date: Dec 2005
Location: Lake Superior
Posts: 103
DanFountain is on a distinguished roadDanFountain is on a distinguished road
Gas Block

Here's a variation on Dave Sutton's gas addition / isolation block for my BP-240 conversion. Since the diluent tank valve is very awkward to reach (ala BMR-500) I wanted all control to be accessible on the over-the-shoulder pendant.

Diluent is supplied to the selector valve (Whitey SS-42XF2) by permanent hose from the onboard diluent supply and from the offboard supply via a CEJN fitting (for the sharp-eyed, you're right - that isn't the proper 1/8"-27 NPT thread on the CEJN male - its actually a BC inflator nipple with 3/8"-24 thread, used for demonstation purposes only). (As an aside, these threads are dangerously similar. A 3/8"-24 will thread into 1/8"-27 NPT for about 3 or 4 threads without binding, and, with enough teflon tape, could be made to seal, but certainly not well enough for life support equipment...) Selected diluent (onboard in this pic) is fed to a manifold on the upper left corner of the rig which supples the ADV, bailout reg, wing and/or drysuit. The manual add valve (the ubiquitous Clippard MJV-2 with stronger spring) feeds selected diluent to the counterlung. Wet plugging of the offboard supply can be accomplished with minimal water inclusion by briefly switching the selector from onboard to offboard, blowing the water out of the CEJN male before connecting the offboard whip.

Comments?

__________________
Try not.
Do - or do not.
There is no try.
-Yoda

Last edited by DanFountain : 22nd April 2008 at 15:27.
(Offline)
 
Reply With Quote