Problems with HOG regs

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The HOG and Edge gear 2nd stages are Apeks clones. Apeks 2nd stages must be attached to hoses using two wrenches, one to hold the locknut still while tightening the hose. If you don't do this, it is very easy to twist the valve body out of position and will cause a freeflow at about 10-15 feet. I found this out from one of my former customers who moved his 2nd stages around and attached 6 foot hoses and such. He kept complaining about my service job, I would check them out, retune them, and return them to him. This happened 3 or four times before we figured out that his "mods" were screwing things up.
 
I've been following this thread and at the risk of raising eyebrows, I would like to offer several observations:
I began using the D1/classic about 18 months ago and have yet to get any water during inhalation, regardless of the position. I frequently dive inverted and/or face up while performing inspections of marine structures. Several of my employees are also using the D1/classic during inspection dives. I have yet to hear of any complaints from them about wet breathing. Prior to purchasing the Hog regs, we were using SP and while I had no complaints with them, they were well worn from years of service. Considering the initial cost of the Hog, the availability of service parts and the positive reviews, it was clear that replacing the SP with the Hog was a good decision. After having logged more than 100 dives using the Hogs, I would stand by my decision.
As an engineer and a person who performs their own maintenance, I think the design of the D1 and the classic second stage is simple, reliable and well thought out (except for the turret). And although it may appear to be similar to Apex, it is not a clone. There are observable differences. One such difference is the seat for the exhaust diaphragm. If one were to observe any of the Apex and the Hog classic second stages side by side with the exhaust diaphragm (valve) removed, one could see the difference. That being said, the effectiveness of the seal between the diaphragm and the seat (plastic body) is dependent upon the pressure gradient during inhalation and the contact area between the two items (one flexible, the other rigid). In the case where a diver has just completed exhalation and the exhaust T is parallel/exposed to high current velocity or scooter prop wash, it is possible that the diaphragm could be lifted from the seat or held open. The effect is similar to air flowing over the leading edge of airplane wing.
Typically, the diaphragm is held seated by a combination of the hydrostatic gradient during inhalation and the compliancy of the diaphragm. There is a very short period of time immediately following exhalation where there is zero gradient pressure across the diaphragm. Since the compliancy of the diaphragm is extremely small, it is possible that water flowing at a substantial velocity over the exterior surface of the diaphragm could create sufficient lift to open it. The potential for this condition increases as the respiration rate increases since there is a shorter time between exhalation and inhalation. Shallow, rabid breathing would be the likely catalyst for experiencing water ingress past the exhaust diaphragm. Increasing the rigidity/reducing the compliancy of the diaphragm would tend to reduce this possibility but would result in a slightly higher WOB associated with exhalation. It should be noted that debris such as sediment, drift algae or macro plankton could become trapped between the diaphragm edge and the body, creating a leak.
Performing a static vacuum test will rule out debris trapped in the seat but would not provide any insight as to why the regulator would allow water to pass by the diaphragm while in high current, scootering or turning one’s head quickly. Covering the upstream side of the exhaust T would tend to reduce or eliminate the dynamic condition of the diaphragm being lifted by water flowing over it and could be used in a process of elimination for determining the leak.

BTW: the SP second stages we were using were the S600 (plastic barrel) and they would leak slightly (very infrequently) when inverted. We also use Cyklon 300 but these never leaked however they do not breath quite as well. The Cyklon were preferred on long dives however as they did not contribute to dry mouths nearly as bad as the S600 due to the metal body.
 
I'm a firm believer, read as user, in Edge/Hog regs... I normally have some where between 4 and 8 student reg sets on hand for my students.

My students love them and I routinely sell the reg a student is using and replace it with another. Last year, I used Edge EXPs sets and at the first of this year, moved to all Edge Epic 1st stages with HOG Classic 2nds.
* These have been slowly replaced with Edge Epic Cold '12s with the swivel braided hoses and Edge Octos.

As an Instructor, I constantly see students try to, "over tighten" the yoke knob, no matter how many times I repeat "don't put your hand on the knob... FINGERS ONLY".
* If there were some crappy knobs, I'm sure Chris is right on it.
* Also must agree, that when swapping hoses if you don't use two wrenches you will cause the 2nd to be out of tune and it will leak or free flow.

I teach students to test their regs before attaching to the tank valve, by placing the mouthpiece in their mouth, BLOW and then gently suck. There should be no leaking when they inhale.

I just added one of the Edge TI regs to the stable for use by my DMc son.
IMG_0513.jpgIMG_0512.jpg
 
I dive Apeks ATX40. It tends to breathe a bit wet when I am looking up. My son dives Hog classic and has never had it breathe wet in any orientation. He has ~ 90 dives on the regs.

However.

On Monday we did a dive in a high current site, Lock 21 on the St Lawrence. Doing an air share at the safety stop - we do this regularly back and forth - his secondary was breathing very wet, so I did not stay on it at all but returned promptly to my own reg. On examination at the surface, it appears that at some point during the dive the current folded the exhaust valve on his secondary. In a pinch I could still have managed, but I did not need to so I did not.

FWIW, this is the highest current site we have ever dived where we were not drifting. For the second half of the dive we were pulling ourselves along handrails against a stiff current for ~ 300', so the effective force acting on the regs was increased.
 
I could suggest a design improvment or two.

My first design improvement is a redesign of the plastics and/or exhaust flap. The exhaust flap is dimensionally larger than the plastics that surround it, and I'm not talking about the exhause hole. The exhaust flap issue is 100% about the giant stride for us, I don't know about a garden hose, but that would easily cause the problem. What happens is the exhaust flap literally rolls backwards 180-degrees onto itself becoming trapped against the body plastic. If the body plastic was large enough such that the exhaust flap could not touch the sides of the reg, it would completely eliminate missed dives due to needing to get needle nose pliers and roll the exhaust flap into a flat (normal) state. My wife and I had this problem repeatedly, in fact, it was so annoying we replaced two sets of Hog setups for DiveRite XTs for our doubles rigs about two weeks ago. An improved design that addresses this issue is quite easy to imagine.

Another possible design change to correct the aforementioned problem is a less "floppy" material used as an exhaust flap. The exhaust flap's flexibility presents an issue as if it were more rigid, enough so that it can't fold over on itself that would also solve the problem.

The other issues is these regs just don't hold a tune. I'm not sure if it's this plastic hardness or that plastic hardness, but they do seem to need at least quarterly tuning or anytime they go on air travel. We actually started bringing reg tools in anticipation of having a freeflowing reg upon arrival at our destinations.

The HOG regs are quite good regs, but they do require some knowledge on how a reg works or you'll miss dives in my experience.
 
Have other people experienced needing to tune their HOG reg on a regular basis? Or have they found getting it an annual/biannual checkup (whatever is recommended) does the trick? I'm all thumbs and no mechanical/engineering knowledge so I wouldn't really be able to do any sort of fix it myself things.
 
I have nine of them as my personal regs. Doubles set, sidemount set, two singles sets, and three stage bottle set ups. What I have found is that if I set them as suggested in the manual after an initial service they sometimes require a tweak after say 50 dives. Not all of them though. That tweak takes about two minutes. After that they usually go until the next service without needing touched.

I don't do a lot of high current dives but have on occaision done them. Only time I had a wet breather was inverted and breathing pretty hard.

When I have had to adjust a reg for someone it takes little time and honestly any competent tech can do it in a couple minutes.
 
Actually just picked up a Hog 2nd as a spare for the gear bag this evening.
 
I just put two dives on my brand new HOG Zenith yesterday. I was diving Cove 2 in Seattle and had the same free flow issue others are talking about. My reg slipped out of my hand and dropped into the water and started to free flow. I grabbed it and put my hand over the mouth piece and stopped the free flow. I let the Zenith hang in the water again and it free flowed once more. I turned the tuning knob a bit and it seemed to help out. All in all I loved the way this reg breathes.

Today I was draining off a tank with my Zenith and felt air leaking out at the hose end closest to the reg. I know I did not use two wrenches to tighten the connection when I put an o-ring so does that mean I messed it up and need to send it to a tech to have it checked out?
 
I just put two dives on my brand new HOG Zenith yesterday. I was diving Cove 2 in Seattle and had the same free flow issue others are talking about. My reg slipped out of my hand and dropped into the water and started to free flow. I grabbed it and put my hand over the mouth piece and stopped the free flow. I let the Zenith hang in the water again and it free flowed once more. I turned the tuning knob a bit and it seemed to help out. All in all I loved the way this reg breathes.

Sounds to me like a very well tuned reg doing exactly what it should do.



Today I was draining off a tank with my Zenith and felt air leaking out at the hose end closest to the reg. I know I did not use two wrenches to tighten the connection when I put an o-ring so does that mean I messed it up and need to send it to a tech to have it checked out?

Verify the location of the leak in water. Even a finger tight connection should not leak (until it loosens further). The o-ring sealing that connection (if I understand you correctly) should already be installed in the hose. It may need to be check to see that it is not damaged.
 
https://www.shearwater.com/products/swift/

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