Question Scubapro DIN Conversion - to DIY or not to DIY?

[steinbil]

Why on earth would you use a luggage scale and not an actual torque wrench?

It's simple, cheap and highly accurate, as opposed to most torque wrenches. Especially at the lower torque range, a common click type wrench will be much less accurate.

Torque wrenches are fairly cheap and have lots of other uses. I don't know the Apeks spec but the SP spec on the main DIN retainer is quite a bit more than "snug".

Indeed the DIN retainer should be tightened to 20Nm and typically comes loose when under tightened and/or when people turn the reg body to unscrew from the valve.

 

[Tanks A Lot]

[...]
do you really think there are manufacturers out there building regs Non compatible with 300bar valves, now that would be interesting
[...]

They certainly have and some still do!

• Take the ScubaPro MK2+, up until it's production end somewhere around 2009, it had the option of the 200bar handwheel (10.400.125) or the 300bar handwheel (10.400.126)
• Cressis AC2, amongst most others from them, can still be ordered with either a 200bar assembly (HZ735158) or 300bar assembly (HZ735157).
• Aqualungs Calypso (Non ACD) can still be ordered with a 200bar assembly (RA119112).

The three above are probably the most widely used regulators worldwide, being in a ton of rental fleets. I have to agree with you that 200bar only systems are getting more and more rare and I was certainly wrong to write 232bar previously! ScubaPro for example has dropped this completely if I'm not mistaken and others never offered them to begin with.

232 bar regulator with its more than 5 threads fits 300bar din valves

But that would make it a 300bar compliant regulator by definition.

DIN477-1 lays out the G5/8" BSP in connector #13, which equivalent to DIN EN 144-2:1999-02. This is a 200bar connector, 5 threads.
DIN477-5 lays out the G5/8" BSP in connector #56. This is a 300bar connector, 7 threads.

 

[lexvil]

I hate to break up a good semantic battle but who can explain why i can screw a DIn into 200 valve with 5 turns but the same DIN into a 300 valve takes 30 turns?

 

[Gone for diving]

I would definitely rethink that, having known a few techs who swore that they could get to manufacturer's specs without the use of torque wrenches, even though the shops had them, right there on the rack -- and challenged three to do just that, years ago.

If I recall, one was under about 6 Nm, prone to loosening -- and the other two were over about 11 Nm. Of the three, I was more concerned with the over-torquing, since brass is a great heatsink, but is notoriously soft and easily prone to damage.

On occasion, I can get fairly close, but I am not willing to roll those dice -- and verify with a torque wrench . . .

Just to throw wrench into this.
Was that dry threads or lubes thread? If so what lubes? Makes a big difference.

What I find annoying is when manufacturers use really fine thread counts. I know in theory its suppose to be stronger. But in practice and real world, it tends to give more problems.

 

[rsingler]

I just find it sad that folks are still here arguing about the utility of using specification torque.

Yeah, my first instructor said torque wrenches were unnecessary, too. So that's the way I was taught.

But it didn't take me more than a decade to find out how wrong he was. As @Bigbella said, brass is soft. I'm slow. It took me a decade to find out he was wrong.

But he was wrong. Torque to spec. Lube only per spec. Truth!

Unless the engineers are just making it up when they create the specs.