Just for the gobble gobbles- Guess the reg(s) I’m restoring

[Mobulai]

While things dry off before approaching assembly, and I gather the will power to continue this (in a way scary) project (as a noob)..
Can you guessed what 2nd stage(s) I’m rebuilding here?
I’m trying to take advantage of the induced slowness; otherwise it shouldn’t be that hard (since I learned about that stuff over here, so at least the “usual suspects” would need but a minute)

See how many spoilers/hints you’ll take to get it right, last one is the answer


Hints:

- it’s Scubapro
- end balanced barrel obv. (ignore the extra stuff at the edges: the vintage mk2, and other scary partial 2nd stage)
- they’re gonna be frankenregs

——

- they’re are notoriously annoying to tune
- I have no idea how I’ll be able to tune them

——-

- newer simpler variants still exist in the SP lineup

——-

- had an awesome feature that died feom SP lineup right after their debut

———————

G500/s600(1st gen) with pneumatic seat-saver adj knob


This is just my (bored/convoluted) way of sharing a day in the life and saying this after 11 months registered here (and a few years lurkingg:
Thanks to everyone on this awesome board, I’ve learned so much already (and have much more to learn still); and so many of you have been extremely helpful and patient with my noob-ass questions, and even supporting me with awesome goodies and toys, couldn’t have gotten from absolute noob to “not a lost case” noob without the collective wisdom and communal sense that thrives around here

Y’all are awesome and I’m thankful to have you in my life/hobby

I love you all without have met you, I hope y’all are doing well today

 

[Mobulai]

These are turkeys but the case can house s600 internals.

I honestly can’t tell which case was from which reg — I started with both and that’s where I ended up
Both are the same turkeys now that they have both metal barrels

 

[lexvil]

I honestly can’t tell which case was from which reg — I started with both and that’s where I ended up
Both are the same turkeys now that they have both metal barrels

Those metal barrels are with the trouble, aspirator hole is tiny and the pneumatic adjuster is not worth the bother, there are add on metal barrels and adjuster that just breath and work better, I spent a bunch of time and effort messing with the 500, wasted effort when the plastic barrels of the second generation 600 will really out perform them with so little effort.

It a great hobby to learn about why some ideas die so quickly, like an original pilot, amazing breather but such a pain compared to the converted ones.

 

[Mobulai]

Up to this point I had only noticed it in a G250 schematic from 1993 and B/A from 1992 and so thought it was a short lived item.

I found 4 in total, all of them came from some eBay finds, a converted 109 (and old duro poppet in a baggie), a 250, one in this g500 (it had the S wing installed but the seller sent also a baggie that had it) and the last was part of yet another closure sale on it’s own
I kept 3, and gifted the 1st one (as I couldn’t tell what it was and punching seemed like an advanced technique back then when I did the tech seminar)
The 3rd that I have I wanna send to someone who can 3d scan it in hopes to try and print it — if we can recreate it (and collect the stems of blue poppets) there is room to make it (in a limited way) available to others

 

[Mobulai]

It a great hobby to learn about why some ideas die so quickly, like an original pilot, amazing breather but such a pain compared to the converted ones.

It’s indeed an „academic“ interest — I like my g260s and on most dives that have mild+ risk I use nothing else
Maybe a 250 or 156 as a second — but that’s it

 

[Mobulai]

wasted effort when the plastic barrels of the second generation 600 will really out perform them with so little effort.

simplifying to the newer knobs (with the “normal”/separate balanced chamber) — would the metal barrel be better: dry mouth/heat exchange ?
Would the disadvantage be the smaller aspiration hole?
What happens of I bore it out? (I know bad for corrosion — but again, theory)

 

[lexvil]

simplifying to the newer knobs (with the “normal”/separate balanced chamber) — would the metal barrel be better: dry mouth/heat exchange ?
Would the disadvantage be the smaller aspiration hole?
What happens of I bore it out? (I know bad for corrosion — but again, theory)

Corrosion is the main problem with drilling the hole bigger, small less flow. These barrels cannot use the newer adjustment knobs, you get s600 metal barrels but I personally have never been able to actually notice a difference in dryness, just not enough surface area.

 

[happy-diver]

The introduction of my D400 into the equation was due to the Air 1 parts in your photo
The right plugged reg exhausts give me bubble free right side of head Paralenz footage
Man!

See me smiling and waving see my head can't miss it see the Paralenz bolted to the side
Man!

 

[Mobulai]

The introduction of my D400 into the equation was due to the Air 1 parts in your photo
The right plugged reg exhausts give me bubble free right side of head Paralenz footage
Man!

View attachment 872395

See me smiling and waving see my head can't miss it see the Paralenz bolted to the side
Man!

Oh that’s a very cool hack - I gotta try that out when I make it to the water

Speaking of paralenz, how do you mount it to your mask? And how’s yours battery’s fairing?

 

[Mobulai]

After finding the same thing, multiple tries to engage the poppet, at some point I realized my success rate was improved when the lever was folded back and resting on the edge of the case by the air inlet vs laid down and resting flat on the barrel.

After ruffling some dust in some old threads (great collective wisdom) I am starting to realize I might be missing something terrible and crucial

On the spare plastic barrel and a curly foot lever I started messing about with the blue “eraser head” poppet, and for the life of me I couldn’t get it to work — I thought I could get it to engage, but it’s not, it kept getting stuck with the seat at the lever feet (looking at it from the orifice side/orifice removed), never could get it beyond that, even when I bent out the legs in hope it moves further

For the “most part” is what I used to say until I found out why SP wants the lever changed. Several years ago I didn’t change the lever sent the reg out for a dive. During the dive the lever slipped from the poppet shoulders and laid flat, not giving the diver any air. I spoke with a couple of people outside of SP and three people within SP and all reinforced that the lever, the diaphragm, spring, and balance chamber need to be replaced when changing over to the s-poppet. In my notes on the schematics it is written in red reminding me not to forget to change out any components when changing to the the newer poppet. I will no longer take the chance nor use the words “for the most part”, especially when it comes to dealing with customers, students, acquaintances, family, or friends. I learned my lesson.

There are 3 levers, 2 non curly feet ones, which are you talking about? Thanks

View attachment 724085

I'm mostly using middle ones in G250s without issue.

Happened to me on a 109 converted to BA, when I replaced the good old two-parts grey poppet with the newer one-piece S-wing white poppet.
Luckily this happened outside water.
I immediately switched back to the old poppet, replacing the seat (which was retained by a metal pin) and the O-ring.
I learned the lesson: the new S-wing poppet REQUIRES the new lever with larger feet (which is not necessarily curvy - I have a couple of levers with large feet which are flat, not curvy, and they work well with the S-wing poppet).

Found it (G500 but would apply to G250). Indeed this pertains to the difference between the two older verions of the lever and the one-piece vs two-piece poppet which pre-date the current s-wing poppet with two orings. So, in conclusion, do not use the narrow tabbed/footed non-curly level with newer poppets. I have yet to find one of those. The older lever with the wider tabs is perfectly safe to use.
View attachment 723716

Okay, folks! I've gone through as much as I can stand tonight on the poppet and lever evolution. Attached to this post is an Excel spreadsheet which references Schematics and Service Bulletins. Most are available on Bryan's VDH site in electronic format. I'm scanning those I can't find on VDH and will send them to Bryan. I can scan and send to others of you that are interested.

April '85 - The conversion kit comes out to shift from the Adjustable 109 to the Balanced Adjustable
I can't find a BA schematic earlier than 1988 that shows the Blue balanced poppet - HELP!
Jul '88 Bal Adj schematic, Revision B shows the Duro poppet and the Blue balanced configs on same schematic
The lever is the original square foot 11.109.105
Jul '88 G250 schematic, Revision A shows Blue Balanced poppet and 109 lever; Inlet Tube is 11.250.102
Sep '94 G250 schematic, Revision D shows Blue Balanced poppet, 109 lever, BUT a new inlet tube 11.200.102. Typo????
(I have an e-mail in to Rene Dupre on this)
May '97 G500 schematic introduces the one-o-ring white balanced poppet with a sleeved plastic barrel and the curly lever 11.250.141. This is the first case of the curly foot lever I can find, and first instance of the white balanced poppet
Dec '97 G200B schematic shows Blue Balanced poppet and old 109 lever; need an earlier G200B schematic, as the G200B balance kit is referenced in Dec '97
Jun '98 G250 schematic shows introduction of EU version with first notation of curly lever 11.250.141 in G250. Also introduces white 1-o-ring balanced poppet to the G250; this curly lever and poppet are in an unmodifed barrel 11.250.102 UNLESS they changed the design but kept the part number. Schematic doesn't make housing look different.

And on and on and on...
Lots more incremental changes, like the S-wing poppet in 1999, the G250HP Crystal using an S600 barrel, and more housing changes, etc., etc.
Will update this spreadsheet as I have the energy to go through more schematics.

Now my big question — in contrast/ as a corollary to updating poppets and the slippage issue above, can the grey poppet engage properly with the newest levers, or is there a further risk here of some horrible thing happening (esp that the new lever feels like it bends a bit while removing it from the barrel vs the old g250 ones that I worked on before)?
Or should I also downgrade the levers to match the poppet?
is this experiment even worth it if I have to look for old levers (and find a way to straighten them as they’re all probably bent, and I have no Idea what/where that „Herman tool“ is…); it’s starting to feel like a whole other wormhole in the „darkside“

I remember I read somewhere Couv (rip) once ask about forward and backwards cross-compatibly (probably was about something else entirely) — I’m wondering something similar here

(Help! Paging the Dr.)

 

[rsingler]

At this point, it's getting a little difficult to figure out what the question is.
So...a few miscellaneous observations.

Seat material - You'll note that Scubapro top hat seats are quite thin, especially compared with aftermarket seats. The advantage that confers is wider valve opening. What happens with a soft, thick seat is that while the soft material requires less spring force to seal, the knife edge depresses into the seat a greater distance. As a result, the initial X degrees of lever travel are used to lift the seat away from the knife edge, as the springy material resumes most of its original shape. Even though the valve begins to leak as the lever is depressed, there's no meaningful air delivery. Even if your lever starts as high as possible, part of its travel is wasted. In contrast, with a thinner seat, the plastic poppet backs it up, and when the lever is depressed, the seat immediately moves back, creating an air delivery gap.
Alternatively, a harder Durometer seat will disengage more quickly at any thickness, but requires a perfect knife edge.

Lever engagement difficulty - there are two flavors here: difficulty getting the poppet into the proper position, and difficulty keeping the poppet engaged on the lever feet.
If your poppet disengages from the lever, that combination is deadly, for obvious reasons. The valve will fail closed. I have neither measured nor tested all the possible combinations, so I'll defer to @Mobulai 's inquisitiveness for the answer as to whether there are dangerous combinations of barrel, poppet and lever. @shurite7 's comment confirms that there are indeed deadly combinations, though I think the bigger factor is a) increased spring force of a badly tuned reg, combined with b) a slightly bent lever, added to c) a worn boss that is supposed to prevent the lever legs from spreading during normal operation.
As for poppet insertion, most modern Scubapro barrels will automatically spread the lever legs slightly, when you lift the lever past vertical and the legs press against the rounded ridge next to the oring groove. If your barrel won't help you, simply thread a loop of zip tie between the barrel and the lever leg on each side to spread the legs 1mm each, and the poppet head will slide easily past the lever feet. I try to never remove the lever at all.

The latest lever iteration may be too high for the G250 and G500 case.

Herman Tool - bending the lever feet symmetrically without a Herman Tool is a simple matter of closing a LARGE adjustable wrench against both feet and pressing the lever in the desired direction. Alternatively, a large Vise-Grip plier will do the same thing. However, the feet of a curly-foot lever will be damaged by either tool, unless you grasp it with the very tip.

Finally, the G500 balance chamber was a marvel of design, being one of the earlier "seat saver" designs. However, the combination of tuning difficulty for technicians, combined with friction in the mechanism preventing most of the seat-saving movement resulted in its abandonment in favor of a simpler micro-adjust mechanism.

But not every change that Scubapro makes is an advance. Sometimes they create a poor design and just won't admit their mistake. In that vein, think rusting A700/C350/C370 knob internals (11.650.105), sticky S620Ti microadjuster, or bringing back the center-balanced valve in the D420, but omitting the coaxial diaphragm/exhast valve.

And remember, straightening a bent lever may create a stress microfracture in the metal that may separate during a dive. Same thing with adjusting lever height with a Herman Tool. Do it at your own risk, and only a little.