Tuned to Freeflow?

[foglesre]

Am I the only one who's new HOG second stages were tuned from the factory to freeflow?

I purchased a pair of these back in November. I mated them with my trusty SP Mk25 (I like the fifth port and I don't want DIN if I'm rec diving), which has an IP of 130 psig. Right out of the box, both freeflowed. Very disappointing.

A couple of other nitpicks--I find the assembly ring for the face plate excessively tight, like there's not quite enough clearance on the threads. It was much easier to assemble and disassemble my old Oceanic Alpha 7s (I miss those regs...). Also, the purge button stuck open on my on one occasion. I'm not sure if a piece of sand got stuck in space around the purge button or what, but hopefully that doesn't happen often.

Everyone seems pretty happy with their second stages so I'm assuming they are not all free flowing out of the box, but for me it was two for two. Good thing they're offering training, but from my experience they ought to include a repair manual in the box...

Bob

 

[Bubbletrubble]

It's considered standard practice to tune the second stage after attaching it to a properly tuned first stage. Often times, second stages are tuned right out of the box to "work" properly...sometimes they aren't. It sounds like you were a little unlucky.

FWIW, I like to tune my second stages so that they are on the edge of freeflow because I like an easy-breathing reg. It's possible that your HOG second stages were very close to being tuned similarly. Probably all that was needed was a very slight adjustment in the lever height. This is actually very easy to do and necessitates disconnecting the reg hose from the second stage in order to make the adjustment.

Tuning the second stage should be fairly straightforward. Have you contacted the manufacturer to get instructions on how to do this? If so, were the instructions clear? (I realize this is the manufacturer Q&A forum. )

BTW, I agree 100% that an official repair manual should be included in the box that outlines the tuning process...especially if the regs are going to be sold online and will have to be assembled by the buyer.

Thanks for sharing your experience. It's especially helpful to prospective buyers.

 

[herman]

Define what you mean by freeflow.
If you mean a slight flow when the cracking pressure knob is set to minimum but stops once the control is cranked in a little, sounds like a perfectly tuned second stage. If you mean it violently freeflows when the venturi is set to max and the purge is bumped, again, a correctly tuned reg.

 

[foglesre]

By freeflow, I meant that the adjustment knob had to be turned in about 75% to stop a continuous flow of air. It was way past being on the edge of freeflow with the knob turned all the way out.

I understand that typically a new regulator should be tuned to a first stage, but if my understanding of balanced regulators is correct, a balanced second stages should be fairly insensitive to a bit of IP variation. I would not have thought that it would be this far out of tune.

Having read Regulator Savvy, I have a pretty good understanding that it is theoretically fairly easly to detune this myself, but as Regulator Savvy says, it good to have the mantufacturer guide to do it right.

I would greatly appreciate if Dive Rite in Scuba (where I bought the regs) or Edge Gear would send the appropriate manual to provide instruction on tuning these HOG second stages.

Bob

 

[Bubbletrubble]

By freeflow, I meant that the adjustment knob had to be turned in about 75% to stop a continuous flow of air. It was way past being on the edge of freeflow with the knob turned all the way out.

IME with similar regs (assuming that there's no damage to the orifice, the LP seat, or the poppet spring and the IP has a reasonable setting), this issue can be very easily addressed by lowering the lever height. This is done by removing the second stage from the reg hose to access the crown orifice. I'm not sure whether orifice adjustment requires a hex wrench or a flathead screwdriver since I haven't taken one apart and no freely downloadable parts diagram/technician manual exists. With similar regs, turning the crown orifice clockwise lowers the lever height whereas turning it counterclockwise raises the lever height.

Begin the tuning process with the inhalation adjustment knob fully open (turned out counterclockwise) and the Venturi switch in the (+) position...then gradually lower the lever height until the freeflow just barely stops. Without an inline adjuster, this will entail several cycles of connecting the second stage finger-tight, pressurizing, assessing absence/presence of freeflow, depressurizing, disconnecting reg, adjusting orifice, connecting reg, etc. Once you have the lever height set, do some test purges and test breathes. With the Venturi lever set to (+), hitting the purge button should set off a loud purge that stops when the Venturi lever is switched to (-). Subjective breathing should be fairly easy (or whatever you are comfortable with). Verify that the cracking pressure changes appropriately when turning the inhalation adjustment knob. In a couple of minutes, your second stage will be properly tuned.

I understand that typically a new regulator should be tuned to a first stage, but if my understanding of balanced regulators is correct, a balanced second stages should be fairly insensitive to a bit of IP variation. I would not have thought that it would be this far out of tune.

With new regs or regs following an overhaul, it is fairly typical to have to detune them a little as the LP seat "takes a set." That's essentially what you're doing by turning in the adjustment knob 75%. IMO, I don't think that your second stage was really that far out of tune. If you follow the procedure I described above, it should be a straightforward fix. Good luck with it. Hopefully, as soon as he becomes aware of this thread, cerich will send you an official set of tuning instructions.

 

[cerich]

sounds to me like the 'stuck" purge button was simply the venturi keeping the valve open, pretty common. Just put your a finger in the mouthpiece opening and it stops 99.9% of the time.

 

[cerich]

IME with similar regs (assuming that there's no damage to the orifice, the LP seat, or the poppet spring and the IP has a reasonable setting), this issue can be very easily addressed by lowering the lever height. This is done by removing the second stage from the reg hose to access the crown orifice. I'm not sure whether orifice adjustment requires a hex wrench or a flathead screwdriver since I haven't taken one apart and no freely downloadable parts diagram/technician manual exists. With similar regs, turning the crown orifice clockwise lowers the lever height whereas turning it counterclockwise raises the lever height.

Begin the tuning process with the inhalation adjustment knob fully open (turned out counterclockwise) and the Venturi switch in the (+) position...then gradually lower the lever height until the freeflow just barely stops. Without an inline adjuster, this will entail several cycles of connecting the second stage finger-tight, pressurizing, assessing absence/presence of freeflow, depressurizing, disconnecting reg, adjusting orifice, connecting reg, etc. Once you have the lever height set, do some test purges and test breathes to ensure that the lever height is set appropriately. With the Venturi lever set to (+), hitting the purge button should set off a loud purge that stops when the Venturi lever is switched to (-). Subjective breathing should be fairly easy (or whatever you are comfortable with). In a couple of minutes, your second stage will be properly tuned.

With new regs or regs following an overhaul, it is fairly typical to have to detune them a little as the LP seat "takes a set." That's essentially what you're doing by turning in the adjustment knob 75%. IMO, I don't think that your second stage was really that far out of tune. If you follow the procedure I described above, it should be a straightforward fix. Good luck. Hopefully, as soon as he becomes aware of this thread, cerich will send you an official set of tuning instructions.

why, you just gave a pretty darn good set of instructions

One thing to add, the oriface on the HOG second stage is old school stainless, if you just start turning that oriface with a hex key or better yet a inline adjuster (Scuba Tools) you'll end up cutting the LP seat and causing problems. I recommend you tune the second stage while also slightly depressing the purge button while you turn the oriface, then stop turning and let go of the purge button and listen for air leak, if there is then you turn in more with a slight depress of the purge, repeat as necessary.

Make sure you have checke dthe IP of the first stage before you do all this, otherwise you may be trying to solve the wrong problem....

 

[cerich]

Dear hog reg users

please understand that hog regulators have been specifically intended for the technical diver.

A technical diver should have been trained in the very basic techniques of checking intermediate pressure and match tuning a second and first stage.

If you have not been so trained, edge/hog highly recommends you seek a competent technical instructor or service technician to properly tune your regulators.

 

[foglesre]

sounds to me like the 'stuck" purge button was simply the venturi keeping the valve open, pretty common. Just put your a finger in the mouthpiece opening and it stops 99.9% of the time.

I apologize if that's what it sounded like, but that was not even remotely it.

No, in fact, the purge button was stuck down. Imagine pushing the button in so that the surface of the button is at a different level than the face of the regulator. Now imagine removing your finger and having the button remaining depressed, slightly cocked at an angle, not returning. That's what happened. I tapped the button and it released. I was able to replicate immediately following, but it did not occur again.

Likely a grain of sand caught in the clearance between the botton and the regulator face. (I was shore diving in Bonaire.) Hopefully not a common problem.

I will assume you were not implying I'm an idiot. I know what a freeflow is and how to stop it.

I'm really not trying to bash these regulators. I think they are great quality and ultimately a good value. I am impressed the design and construction of them (perhaps not the assembly). I love the idea behind them. I am just relaying that my first experience with the pair I bought has been less than perfect. So far they have not been as trouble free as, say, my SP S600.

I'm also very happy with my HOG SPG and I look forward to converting my D1 to a 5 port and giving it a try.

Bob

 

[foglesre]

Dear hog reg users

please understand that hog regulators have been specifically intended for the technical diver.

A technical diver should have been trained in the very basic techniques of checking intermediate pressure and match tuning a second and first stage.

If you have not been so trained, edge/hog highly recommends you seek a competent technical instructor or service technician to properly tune your regulators.

I recently completed my first tech diving certification--Full Cave. I am well aware of checking IP and the impact it can have on second stage tuning. However, I have never been instructed in the tuning of a second stage, other than by reading Regulator Savvy and the very good description above.

That being said, I have swapped several second stages (SP S600, G250, G250HP) with several first stages (2xMk25, Mk20, Mk18) and I have never had to tune a regulator before.

That's a good disclaimer that you provided. It would probably be a good disclaimer to include on a vendor's website. Or perhaps something along the lines of, "HOG first and second stage regulators are sold individually and not as matched sets. Second stage tuning to match first stage intermediate pressure may be required prior to use."

Bob