My favorite mod.

[vance]

If you've been around this forum for a while, you know Vance likes a mod.

Out of all the conversions I've done, I think my favorite is the Misuba rev5. This is a Healthways single stage valve with Conshelf balanced parts installed in the valve body, with a JB snorklejet inspired "Ghost" air director.

It is installed in Mistral boxes, and has a duckbill eliminator exhaust valve.  It  is a great breathing single stage regulator, perhaps as good as a Mistral, but spooky quiet.

IMG_5159 by Vancetp, on Flickr

I have been looking for internal photos of this one, and haven't been very successful... Huh. 

I will take the thing apart and get some pics!

[vance]

Here's a photo showing the "ghost" air director. It's name comes from the unfolded cutout looking like a cartoon ghost.

DSCF3162 by Vancetp, on Flickr

IMG_4184 by Vancetp, on Flickr

This is a comparison of the Conshelf guts vs Healthways. The Conshelf parts fit nearly perfectly in the HW body. There is a slight difference in diameter of part of the bore and the USD poppet. Everything else is identical. Stuffing Conshelf parts all up in a HW valve was first suggested by Creed, some years ago. This only works in the early, long HW valves.

100_1069 by Vancetp, on Flickr
 
A new HP pin was required. The left one is a stock Scuba pin, the middle is a HW single hose pin, and the right side is the modded Misuba Rev5 pin made out of the single hose part.

[nikeajax]

Phil, it all sounds so easy until you get to that caveat at the end there

Here's the pattern in case someone wants it:



JB

[cg43]

Hi Phil



Bottomline (Healhways parts), third part from left , called Restrictor .
What is the diameter of the small hole or orivice ?
and is there any explanation of its function ?

Greetings   Rainer

[vance]

The restrictor functions as a "reserve". As the bottle pressure reaches somewhere around 300psig, inhalation is noticeably harder and the diver is cued to start ascending. This was before SPGs were used.

There are two restrictor types and two different orifice sizes. The one shown above is turned out of a billet and these only have tiny reserve holes. They are found in early Scubas. The holes are similar to the tiny drillings found in SPGs. At full bottle pressure, a lot of air can escape through a tiny hole.

The other type is stamped sheet metal. The two orifices found in the stamped ones are a tiny hole for a reserve and a larger one meant to allow air past w/o restriction.

The plate is necessary with or without "reserve" b/c it also functions as a o'ring holder and spring pad.

[vance]

Apr 14, 2024 12:32:44 GMT -8 nikeajax said:

Phil, it all sounds so easy until you get to that caveat at the end there

Here's the pattern in case someone wants it:



JB

Well, yeah. It is.

But, you have to have a pin that fits through the Conshelf HP poppet to actuate it and for balancing! The long thin bit is a piece of hardened stainless steel rod that fits into a drilling in the HW pin body. Red loctite keeps it in place. The lever contact point is the threaded bit, which fits into a threaded drilling on the other end. It is a stainless steel setscrew.