Manifolds - DGX vs Thermo

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three years of having the DGX valves and isolator. and no problems*.

* - the "low profile" valves gave my LDS fits, and he actually ruined them as there was no flat at the base of the neck to put a wrench on for removal (vip), and he then destroyed the valve (and promptly purchased me a replacement) by wrenching on the valve head. The tall profile have this if you desire. The tall valves are also easier on the hands to carry.

I find that the quick smack with the heel of my hand has been more than adequate for seating and un-seating the valves for the last 26 years I have been doing this....

YMMV
 
Are you saying you feel vindicated?

I sure do!. LOL

@victorzamora here is a pic of the burst disc.

20160826_174919.jpg
 
Thanks for all the responses, which confirm I should save the $150 for other toys. I'll need to think some more about regular vs. tall valves. I'm 5'9" and will probably go with LP85s.

Another quick question: I've seen (used) bands listed with different "heights" - 2", 1.75", and even 1.5". DGX doesn't even list this dimension for their bands, but it looks about 2" from the photos. My gut feeling is that 1.5" would be flimsy, especially with the 5/16 or 3/8" holes. But I have a habit of over-building everything I make in my shop. Does size matter (here)?
 
* - the "low profile" valves gave my LDS fits, and he actually ruined them as there was no flat at the base of the neck to put a wrench on for removal (vip), and he then destroyed the valve (and promptly purchased me a replacement) by wrenching on the valve head. [....]

I find that the quick smack with the heel of my hand has been more than adequate for seating and un-seating the valves for the last 26 years I have been doing this....

YMMV

Some of the scuba tool web sites have a "wrench" that threads into the DIN fitting, for removal of stuck valves that do not have flats.
 
The DGX bands are about 2.5" I think. Maybe 2.75"

Also, the flats where the bolts go are usually double-triple in terms of thickness when compared to the circular parts of the band.
 
here is a pic of the burst disc.

You, sir, are the bomb. The thermos have that "protective ring" around the burst disc whereas my current dive rites do not. It's not a big deal on smaller tanks, but lugging those LP125s around it really makes a difference.
 
Thanks for all the responses, which confirm I should save the $150 for other toys. I'll need to think some more about regular vs. tall valves. I'm 5'9" and will probably go with LP85s.

The height difference isn't that dramatic when talking about the overall height of a tank....but it's definitely easier to get big hands under the valves with the "long neck" variants. I will say, though, I'm 6'6" with decently large hands and have no trouble with the short neck valves...it's just that I'd take talls over shorts if I got to pick with no cost or hassle difference. I'd never pay to replace good "short" valves with "tall" ones, though.
 
The Thermo manifold uses a copper sealing ring rather than an O-ring on the packing nut. I prefer the O-ring because it requires less torque to assemble.

The DGX valves I have purchased new have come with a 3-piece burst disk that is etched with a pressure rating in the same fashion as 1-piece assemblies. I believe this is a poor design, because the whole point of the 1-piece assemblies is that the etched pressure rating can be relied upon since there are no parts to mix up. I have also found the stock burst disc to be difficult to remove, which I've had to do since I use mine on LP cylinders and want the correct burst disc.

I much prefer the oring sealed bonnet nuts cause I can by a 100 pack of those oring for like $7 compared to $1+ each for those stupid copper crush washers.

1) you still need to torque the oring sealed bonnet nuts damn tight or they can unscrew themselves which is very bad.
2) with the open valve on an empty tank hook up your transfill to any old cylinder of leftover gas, crack the valve and blow the burst disk out (cover the opening with a towel to catch it)
 
I much prefer the oring sealed bonnet nuts cause I can by a 100 pack of those oring for like $7 compared to $1+ each for those stupid copper crush washers.

1) you still need to torque the oring sealed bonnet nuts damn tight or they can unscrew themselves which is very bad.

True, but the actual torque specification is lower, and not as critical.

2) with the open valve on an empty tank hook up your transfill to any old cylinder of leftover gas, crack the valve and blow the burst disk out (cover the opening with a towel to catch it)

Oh believe me, I did that. And then did it with safety glasses, gloves, earplugs, and a full HP cylinder. Which was enough to turn it sideways and push it out a little but still leave it stuck in the threads. IIRC there then ensued five minutes of futzing around with a brass pick, a street sweeper bristle, a crochet hook, and really small needle nose pliers.
 
https://www.shearwater.com/products/perdix-ai/

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