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Post by vance on Jan 25, 2019 23:31:43 GMT -8
Thanks for the explanation and the warning, Luis. I appreciate it, and won't take it badly.
I am very cautious. And, I'm trying to understand how things work as I go along. I am throwing these things out there to get feedback, and advice. Rest assured, I won't try to do any radical mods to the balance chamber. I'm just ruminating, at this point.
As to the float I was talking about, it seems to be just a cushion.
I will check into the book, for sure!
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Post by luis on Jan 26, 2019 6:47:02 GMT -8
As to the float I was talking about, it seems to be just a cushion. I will check into the book, for sure! It seems to be cushion, but it isn't. The small spring is just there to take up any gap due to manufacturing tolerances. |
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Post by luis on Jan 26, 2019 7:09:20 GMT -8
The balanced chamber is not intended or designed to float. The short spring on a Conshelf is just intended to take up the gap from the tolerances. It allows looser tolerances without ever having an interference fit. The Voit MR-12, Titan, Trieste, have a very similar balanced chamber (first stage design) but they don't use the small spring on the back side. You can actually assemble a Conshelf 1st stage without the spring and will work fine. The gap is minimal and tank pressure will keep the balance chamber pushed hard against its supporting ledge. I will give a quick hint of how the balance chamber works: It is a, mechanically supported, low pressure chamber behind the HP seat. On the front of the HP seat inside the volcano orifice is low pressure air. By having a low pressure chamber behind the seat, the pneumatic forces applied to the seat are now balanced. The seat is not affected by tank pressure. The tank pressure is only pushing around the perimeter of the seat, not pushing it, to close or open. I hope my explanation is clear. I highly recommend reading the "Regulator Savvy Book" by Pete Wolfinger. www.scubatools.com/c-23-regulator-savvy-book.aspxIt will explain how regulators work. I highly recommend reading this book. It explains a lot about the pneumatic forces and how they interact to make a regulators work. Please don't take this in a wrong way, but for your own safety, IMHO I feel that you should try to understand how pneumatic devices work before making major modifications. Just be careful (always wear safety glasses, etc), you are now working with high pressure air. I should add that for an actual balanced system, obviously the pneumatic forces have to balance. A pneumatic force is equal to the pressure times the area (the area where the pressure is acting on). F = P x A The pressure inside the balanced chamber is the same as the pressure inside the volcano orifice, that means that for the forces to balance, the areas also have to be equal. In other words, to obtain equal "pressure areas", the diameter of the volcano orifice needs to be equal to the diameter of the stem on the back of the HP seat. I have designed and built several balanced single stage regulators. In some cases I started by using a damaged Mistral body, in other cases I designed the complete body. In any case, were I am going with this is that even when I used the Mistral body, I had to have the volcano orifice machined out and I replaced it with a Conshelf (same as Aqua Lung Titan) volcano orifice. Oh yeah, and in order to get everything to work and fit properly, I have lay it all out in AutoCAD using all actual dimension. Being able to lay out everything with true dimension helps tremendously to analyses all the forces and component motion. To do motion simulation, I just draw all the parts and manually move them into all its possible positions. I do a lot of modeling and analysis before any metal is cut. It is very easy to change a drawing/ model, but once you cut metal, you can't put it back (not easily anyway). On my spare time I am actually working on what I call project Unicorn III (I already did Unicorn I and II). I understand that not everyone has AutoCAD (it is an expensive program), but advance planing can even be done on a drawing board. I used to do it on a drawing board a couple of decades back. There are also some other reasonably priced drafting CAD programs that can be very helpful to lay out something before cutting metal. I understand that cutting metal seems like the most fun part, but you will be amazed how much fun it is to actually lay out mechanical components. Getting started is always the hardest. Good luck |
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Post by vance on Jan 26, 2019 10:20:24 GMT -8
Thanks, Luis. Your explanation seems to back up my idea that this has worked, because the Conshelf parts, including a Titan volcano orifice are all fitted into the HW valve, which has dimensions almost identical to the Conshelf body. While I have no data showing that it works, all is nearly equal, so if one works, there's a good probability the other does, too. The only modification to the guts was a slight reduction in the OD of the soft seat of a few thousandths of an inch to make it fit into the slightly smaller bore of the HW valve body. BTW, I am not interested in designing or building new balanced single stage regulators. The only thing going on here was to determine whether a set of Conshelf guts could be stuffed into an HW Scuba valve, and made to work. It turned out the answer to my question (which was already partly answered years ago by Creed) is yes. And no. Way back in this thread Michael posted pics of his successful stuffing of parts. Others tried to replicate this, but ran afoul of the short/long valve issue. No one seemed to know there are two different valve bodies. Although he had done the parts stuffing, he did not elaborate on whether he had made a pin that worked or if he had outfitted a regulator with the "balanced" valve, and if so, had tested it. I was certain he'd used a long valve body, and the others who tried it used short ones, so I decided to try it for myself. You're right, no drawings or calculations beyond careful measurements and comparisons of the Conshelf and HW valve bodies were made, determining the inside dimensions are extremely close. I posted the measurements a few pages back in this thread. So, I turned a tiny bit off the soft seat and installed the Titan hard seat and the Conshelf parts into a long valve body. So, yes the long HW valve body will accommodate the Conshelf guts. Then, I looked at the short valve body, and saw that the Conshelf balance chamber would not fit w/o some modification to it or the valve body. The space between the circlip groove and the ledge that holds the balance chamber in position very short. Drat. The ultimate use for this would be making a balanced Gold Label valve, but they are all short (as far as I know). Continuing with the experiment, I installed the valve in a regulator. I made a quick and dirty pin and tried the reg on a tank. It delivered air. It wasn't balanced due to the pin/soft seat interface, but it showed that the valve works. I then made a new pin which has the correct interface (fitting up inside the soft seat, rather than just touching the face) and tried that. It delivers air. Is it balanced? Should be..... This shows (L to R) the original HW pin, the pin (supposedly HW) I found to mod, and the modded pin with the correct length probe:    (The black stuff coating the inside of the can is RTV silicone sealer. I was experimenting with coatings. It's been there for at least a year, so off-gassing is minimal if any.) |
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Post by nikeajax on Jan 26, 2019 11:01:37 GMT -8
Phil and Luis, thank you for connecting all of that together for us... Phil, I can absolutely verify that the actuator is a Healthways:  It's a unique part to that model of Scubair  JB |
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Post by technidiver on Jan 26, 2019 11:15:06 GMT -8
Bravo Phil!! I'd cycle it at least 50 times to get it adjusted/fit before taking it into open water. That's the eventual plan, right?
Good job on your work with HW!
TD
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Post by vance on Jan 26, 2019 12:10:31 GMT -8
I'll eventually try it out in the pool. I don't think I'll be doing any open water dives with it, unless I actually follow up with the SnorkleJet equipped Misuba Rev4 (Balanced?) The name of that reg keeps getting longer!
I found the Scuba with the SnorkleJet and a USD hoseloop very divable, but without the SJ, not so much (in the ocean). I felt on the edge of overbreathing the stock Scuba at times, even with the USD hoseloop.
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Post by vance on Jan 27, 2019 16:36:22 GMT -8
As to the float I was talking about, it seems to be just a cushion. I will check into the book, for sure! It seems to be cushion, but it isn't. The small spring is just there to take up any gap due to manufacturing tolerances. I can see how it isn't a cushion in the Conshelf. This is what I meant: the pin travel issue is very different in the first stage regulator (very small, .040" if I remember correctly) than that in the single stage regulator. But, since the pin travel is so much more in the single stage valve, over-travel of the pin CAN be taken up by this extra space, if necessary. I don't know how far the pin moves in the HW conversion valve (that'd be a time consuming piece of measurement), or if it needs any extra room, but if it does, it's already in place. With a short valve, the measurements are critical, because there is no room for any float. In fact, the balance chamber might need to be cut, in order to fit. The pin travel might be too limited, given this restricted space, to provide sufficient air flow to the diver. Or, it might be fine. This would have to be determined. |
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Post by vance on Feb 28, 2019 11:02:31 GMT -8
You've been waiting for it. It's finally ready to be unveiled!! The SJ Misuba rev4 (balanced?) with Commie hoses and a Hope Page mouthpiece.    
It features the SnorkelJet rev2, a silicone diaphragm, and a duckbill eliminator, mounted in Mistral cans with a Healthways HP valve having Conshelf guts all up in it. Purporting to be balanced. It's made to be. Unproven, but possible. Should be. Maybe. Potentially. Hopefully? I should add these notes: The SJ is a modification of JB's design. The "balanced" valve is based on the work of Creed who started this thread. No Mistrals were harmed in making this regulator. The top can was a badly dented orphan supplied by SeaRat for the sake of 'spermentin'. The rest of the stuff is returnable to stock. |
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Post by vance on Feb 28, 2019 16:19:37 GMT -8
But why would anyone want to return it to stock??? Misuba Rev5, baby!
Just sayin'.
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Post by vance on Mar 13, 2019 16:12:48 GMT -8
I am missing 2 case clamps for HW Scuba projects. Here's my latest foray into blasphemy:  It doesn't leak, and seems to be stable. The only problem would be if the cover were to slip, but I can't push it off. I don't like box clips, but what're ya gonna do? This is the regulator pictured above with the RTV coating inside. It has a rubber sheet exhaust valve made out of the stuff the PT makes you exercise with. It's the heaviest grade, doubled. I also used a longer screw to get the clamp over the rubber w/o cutting it. I'm going to try a duckbill made from the top straight section of the flat, silicone USD duckbill TSM sells.  |
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Post by tomcatpc on Mar 13, 2019 21:43:29 GMT -8
Do what you gotsta do... If it works...one more SCUBA in the water.
Mark
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Post by vance on Mar 15, 2019 15:46:08 GMT -8
Yeah, I agree with you. It does't look bad this way. This one is definitely going into the (hopefully) dive-able collection.
That makes 4 functional Scubas. There's only one Deluxe (the Faux'62 with a GL valve and yoke on it) and one GL left. The FX'62 and the Misuba Rev4 projects left me with a set of orphan GL cans with no valve or case ring, and short one Scuba valve.
I was fortunate to find nearly perfect examples of the 3 Scuba set, as well as a beautiful alloy DivAir. A super nice plastic DivAir hasn't appeared to add in, although there's a pretty good one in the Healthways box. A brass one is probably beyond my means even if one turns up for sale. I won't dive the super nice ones in salt water, and probably won't dive them at all.
That means two collections: one is the super nice/pristine regs, and the other one is the regs I'll get wet. Kinda ridiculous, but that's how I roll.
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Post by nikeajax on Mar 15, 2019 17:29:09 GMT -8
Phil, just how many reg'laterz ya got son? The important t'ing is dat you is havin' fun mit dem, ja?  Have you already shown us your blue Divair? (aluminum) JB |
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Post by vance on Mar 16, 2019 9:13:27 GMT -8
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