A Better SPG?

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I either had some weird caching problem or just a brain fart, but I answered your post thinking it was on another thread. Too many projects, multi-tasking windows, and phone calls I guess. Sorry for the confusion.
:idk:



A ScubaBoard Staff Message...

I moved the offshoot SPG comments from the AL80 @ 800' to the SPG thread. :wink:
 
LOL @ brain fart. :)

"I are diver, too." :D

I've got a couple of extra SPGs sitting around... I think I'm gonna drill one out and oil fill it. I just gotta figure out how I'm going to do the little rubber diaphragm...

I mean, unless you want to do it... Not trying to steal your idea. :) It's not like I don't have a million irons in the fire at the moment... :D

Simple solution. I like it. :)
 
... I've got a couple of extra SPGs sitting around... I think I'm gonna drill one out and oil fill it. I just gotta figure out how I'm going to do the little rubber diaphragm...

I mean, unless you want to do it... Not trying to steal your idea...

You're kidding right? That would be great! I wouldn't care if you claimed the ideas as your own, took it to market, made tons of money, and retired to the tropics. I just want to be able to buy a better SPG and enjoy design reviews.
 
LOL @ brain fart. :)

"I are diver, too." :D

I've got a couple of extra SPGs sitting around... I think I'm gonna drill one out and oil fill it. I just gotta figure out how I'm going to do the little rubber diaphragm...

I mean, unless you want to do it... Not trying to steal your idea. :) It's not like I don't have a million irons in the fire at the moment... :D

Simple solution. I like it. :)

Use glycerin for the fill, it's should be available at any pharmacy. Or you could use Lemon Fresh Joy, give the face a golden hue and will make wonderful bubbles if it does break.
 
What's wrong with oil? I've got a ton of Bauer synthetic compressor oil sitting around... Could also use mineral oil or vegetable oil, or anything else transparent. :)

What's the concensus? Glycerine? Oil?

I need to find some sort of standardized rubber stopper so that whatever I do, it can be easily duplicated by everyone, assuming it's successful.

Do y'all think I can just remove the rubber burst plug and reinstall it? I think that it'd be enough to transmit pressure, assuming there's positively no air bubbles in the gauge...
 
What's wrong with oil? I've got a ton of Bauer synthetic compressor oil sitting around... Could also use mineral oil or vegetable oil, or anything else transparent. :)

What's the concensus? Glycerine? Oil?

I need to find some sort of standardized rubber stopper so that whatever I do, it can be easily duplicated by everyone, assuming it's successful.

Do y'all think I can just remove the rubber burst plug and reinstall it? I think that it'd be enough to transmit pressure, assuming there's positively no air bubbles in the gauge...

Mineral oil is used in some compasses. Vegetable oil might be "cleaner."

To ensure no air bubbles, fill it, then top it off by immersing it in a bucket of the oil and letting all the air bubbles out, then plug it while it's still immersed.

What I want to know is, who is gonna take it to depth and test it? :)
 
I've got a 250' working dive happening in late August. Between now and then, a couple of 160' working dives... Otherwise, a whole lot of <30' working dives. That's about it for me. Nothing even remotely near 400' or 500'.

800'? Never had the desire or need. Figure I'd want to outfit more than a few of my guys with Megalodons before going any deeper... Which means a pretty hefty investment.

I could run offshore this week for a 130' dive to test the SPG, but I don't see the point.

It seems like we haven't yet established what the crushing depth is for a 2" brass & glass... So "testing" doesn't make any sense until we've first established that, have found it to be a repeatable problem, then added the oil to see how that improves performance.

Meanwhile, I could go ahead and oil-fill one, but all it's going to do is tell us that it can be done. We haven't established a need or point.

...And I've got a philosophy against creating solutions for problems that don't exist. What can we do to establish that the problem exists? (Even that thought is a bit "off" for me - if we don't know for sure that the problem exists, then is it really a problem? It's not like I need another problem - there's lots of things in life to address already.)

Lemme find out if JJ's doing any deep diving here in the near future - and if he sees the point of oil-filling 2" brass & glasses. He may also have some experience and knowledge about depth ratings on them from the factory...
 
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That's about it for me. Nothing even remotely near 400' or 500'.

You're likely to need more depth than that.
 
Good point. I personally can’t recall any fluid filled depth gauges leaking. I have seen one occasion where several fluid filled industrial gauges were smashed, but that was the smallest part of that mess.

Does anyone have experience with oil leakage from mechanical depth gauges in the last 30 years or so?

SPG no, but I have a suunto compass that sprung a leak... made a huge mess on the trip back n there is an ever increasing bubble.

SangP
 
https://www.shearwater.com/products/swift/

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