Starting down the DH rabbit hole

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There is nothing wrong with Teflon tape if it is used properly. Just make sure it is all captured between the threads so that of it comes loose inside the fitting.

As an alternate you can use thread sealing Loctite. It is an anaerobic bonding and once it is cured, it is inert. Again, you only put it on the male threads, a thread or two away from the air passage.

As @Perryed mentioned, this fitting doesn't have the sealing nipple, therefore there is no chance of making a metal to metal seal.

I don't know if a Teflon washer will work inside. I just ordered one fitting to take a look at it. I don't know if there is a nice flat surface for the washer to seal. It may work, but I will not know until I actually see one.

I am also going to try an O-ring. That will be my preference. I often use Metric O-rings because they come in a variety of thickness (1mm, 1.5mm, 2mm, etc.). I have found a lot more flexibility in finding the best fitting O-ring when I look at the Metric selection. I buy them from McMaster Carr. They have a great selection. I do have to buy them in bags of 50 or 100,but they are not that expensive and I end up with a few spares.
 
My concern about o-ring or washer seals is if the passages to the 3/8 openings are too close to the edge of the 9/16 opening, an o-ring or washer may occlude part of the flow path. Mine should get here today or tomorrow..... I'll post what I find.
 
I was thinking about trying the O-ring on the outside pass the threads. I think the thread relief at the base of the male threads could be a good place to try an O-ring. The O-ring would be captured. The female fitting is designed to seal with an O-ring in that spot.
 
Yes, an o-ring would work there but would have to be very thin not be totally crushed and deformed to the point where it would lose it`s effectiveness.. That`s why I went with Teflon tape. If you find an 0-ring that works, let me know. I would definitely be interested in a few. Would help defray the cost of you having to buy 50 or so. Loctite is a kind of superglue so it would work, but unscrewing it would be much harder.
 
Well, bottom of the bore o-ring is a no go.... I'll play with my o-rings on hand to see if one works as @Luis H describes. But until the rest of my parts come in from VDH, I won't be able to pressurize and check for leaks.
20191108_211029.jpg
 
Well, with no proper stop to keep an o-ring from pushing further down the outside of the hooka port, it looks like Teflon tape per @Perryed installation is going to be the way to go. My parts from VDH should be in this week, so I'll finish cleaning and get it together this weekend most likely.
And lest anyone think it's a complaint, I ordered from a small shop at a very busy time. VDH has been totally transparent about delays due to day job and Kracken assembly on their site, and e-mailed updates when my stuff shipped. In short, their service is excellent, and an irreplaceable asset to the community.
Rant complete,
James
 
Well, it is put together..... there is a very slow leak somewhere, but I think I know where. I used the same adapter that @Perryed used, and couldn't find a suitable way to use an O-ring. So I used PTFE tape (correctly, fully captured in the threads), and on first assembly it had a slow leak (pressurize, turn of tank, leave for 1 hour and IP is at 50 psi). I redid the PTFE tape with more wraps, and now it takes approx 3 hours to drop to 50 psi on that test method. So I think that is the source of the issue, and I can live with that slow of a leak for now. Other fun facts.... I was surprised at how far out the Cyclone 1st stage sticks. The short yoke has lots of wiggle room on it! on first pressurization, IP read 110... I used the old RAM manual from VDH (figured the Cyclone is just an improved RAM at heart) and it call for "approximately 100 psi" for the IP, so I called it a win! I have since seen that others run at 130 to 145, but I'll try it this way to start. Might be a bit before I can get it in the water, but my 9 y.o. designated bathtub tester is anxious to get his hands on it!
While I had it apart, I realized that if the original 1st and 2nd are still good (which they probably are) then I have the critical parts to reinvent the wheel.... so that will become my next big random rabbit hole!
 
Original diaphragm and mouthpiece are claimed to be good. I cast no aspersions, I haven't even had it in hand yet, but my list of minimum parts so far is such:

I too suffer, to a degree, from the Ole Regulator Simplex II; and, from experience, wouldn't trust that that decades-old diaphragm and mouthpiece, is in working order. Similar claims have proved otherwise . . .

Welcome to the cult compound. Kool-Aid anyone?
 
https://www.shearwater.com/products/teric/

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