November 12, 2007 at 10:21 am #779
I thought I publish my project so far. I have been designing new regulator which will go inside main tank. The reasons are simple;
-it won’t take space between gun and tank
-it’s safe since everything is inside tank
-the big forces are all gone and replaced from stretching to compress
-there is good space for relatively big size regulator chamber which is needed (25ccm) for low pressure and wider pressure-range (more usable shots)
-the firing valve is separated from regulator design so one could use any valve available (although it needs connection thread for regchamber)
I already built two prototypes and tested them on dedicated testbench. The regulation works. I did few hundred of strokes and it regulates the pressure everytime to set value. I still need to examine different poppet-valve sealing materials since I am not 100% happy with current implementation. Over few hour period there is some pressure grawling noticeable meaning that first shot will be little faster than rest.
The difficulty for Talon regulator is the filling. It has to be able to handle bigger forces during filling and also has to pass trhough the air from regchamber to the tank. That was the reason for “inventing” poppet-valve to the regulator. It handles both. Eliminates the bigger forces against regulator-sealing and acts as oneway-valve during filling.
The regulator is designed for 300bar and the regulator body can handle 3x that pressure when it comes to strength.
When used with 100bar pressurerange the accuracy from first to last shot is about 1.6% leading to 1.2m/s velocity drop over whole range. Of course there is little bigger variation during string because of other factors.
This is how it should be assembled to the gun….
The princible of regulator…..
-spring lifts poppet-valve’s stem and air starts to flow from tank over valvestem to the regulator chamber
-pressure in regchamber raises and exceeds springdiscs force and regulator pistons moves to the right. Poppetvalve closes.
-shoot and the cycle restarts
-during refill the overpressure in regulator chamber (against tank) will push the poppet-valve open and air will flow to tank
-the regulation pressure is adjusted with big M14x0.5 thread in the “tophat”
-do realise that the flowchannel in poppetvalve is 10x smaller than through the regulator piston. The pressure is always same one bothsides of piston’s heads. So don’t get confused about the “reverse” design.
Prototype number two…
Poppet-valve and integerated sealing…
About the scale of parts….
In the bench the regulator is inside aluminium tube…
It’s not ready yet but it’s a step closer to our common goal… regulated Talon which can shoot consistent shots with wider pressure-range and wider ME range. Next I need to build or get main firingvalve to be able to perform some fieldtests with gun.November 12, 2007 at 11:04 am #27522marcParticipant
I’m working on that mika.
Hang on!!November 12, 2007 at 11:27 am #27523quote Marc:
😆 I am holding my breath already so please hurry!
And I wish to express my public Thanks to you for all the great tips and critical review of that reg design.November 12, 2007 at 6:21 pm #27537shadohParticipant
Mike, looking at your drawings, beautiful as always, I see one flaw in this design.
The chamber with the spring discs is not vented to the outside air. If the Orings that seal off the spring chamber leak at all it will force the regulator to stay open all the time. While it may work for awhile eventually those Orings are going to allow air to bleed by.
This type of design has actually been brought up and discussed before on another site.
Here is the link if you want to take a look.
The drawings I made were purely conceptual and not to spec. I didnt know about things like spring discs and such ) Obviously my design could be improved upon. The bypass valve could even be that single ball bearing you used in another design ).November 12, 2007 at 6:54 pm #27540nebraskaParticipant
Very impressive as always was wondering if by chance you are a rocket scientist by day. 😀 😀 😀 .November 12, 2007 at 7:06 pm #27542quote Shadoh:
I know. Eventually the sun will also burn up. 😛
The question is how long is that time. Is it week, month, year or something else.
There is an industrial device called tooling gas-spring. It is a closed system with high pressure inside (hundreds of bars). The piston is moving a long stroke unlike this application where stroke is only 0.2mm and O-rings are calculated as static load. The factory quarantees 100.000 stroke meters for that gas-spring. It means million strokes for 50mm piston.
Now, I am not saying that regulator performs same but I am curious to know myself how long it will last. If it last few months I can just swap the O-rings inadvance when necessary. If it last only weeks then it’s doomed.
Good notice though. Just remember when you invent new things and someone says it wont work because of this or that keep going and trying. They used to say it’s impossible for man to fly too you know 😉
I like your ideas and designs but again I would suggest drawing in scale. If you take a look of that piston size you might realise how small the stuff are. It’s really difficult to manually make tolareted moving parts in that scale. That thread is good reading. Gives some nice tips. Thanks.
But then again…. thats why I have inline-regulator design in backpocket for plan-b.November 13, 2007 at 2:19 pm #27583
Like I said. There’s always plan-B waiting 😛
This doesn’t mean that I don’t believe for intank regulator – just a backup plan.November 22, 2007 at 6:51 pm #27958
Regulator project is proceeding slowly because lack of free time but I’m getting there one step at time. I still have strong believe that it will work 🙂
Standard Talon tank, regulator, regulator chamber and new firing valve to fit.
The regulator in the rear of package.
Thrilling moment. First time to check will it go inside. I turned regulator and chamber before I first time opened the tank. Blindly trusting that tank thread is what I have heard 😛
phiuf… Whopping 0.1mm extra space in diameter… (M18x1.5 thread in the tank is 16.3mm ID. Regulator is 16.2 OD)
Regulator and chamber is separated from mainvalve and connected with M13x1 thread with O-ring sealing.
Concept of 3rd prototype. It has two pistons – that’s the reason for name “Twin Piston Regulator”. Hey, I have to call it something to separate it from other designs. Besides it sounds cool and powerfull 😀 😀
The second piston acts as oneway valve during refill and also prevents too big load for plastic piston sealing. I have tested it in the testbench for a week already and it works best of the prototypes so far.
Made it from brass since it’s strong enaugh and nicer to machine.
I am still missing valvestem to mainvalve. I was supposed to make it today along with regchamber and some other stuff but the bastard went broken… TWICE. I have too thin diameter in one position which I need to redesign. Unfortunately I can’t continue untill next week and my planned weekend test-session went to toilet also. Oh well… But it’s a long winter and I can’t pretty much shoot outside anyway so I have all the time for this project.November 22, 2007 at 7:23 pm #27960walkonkingParticipantNovember 22, 2007 at 11:17 pm #27972rabbitsParticipant
what the hell mate .u realy r the man at this shit … 😛November 23, 2007 at 5:29 am #27980AnonymousInactive
Your craftsmanship is like something out of a science fiction novel. 8) 8)
DHNovember 23, 2007 at 9:49 am #27986quote dirty harry:
Lol. You guys give me far too much credit for machining skills which I don’t deserve nor have. I just like to polish stuff with sandpaper 😀November 23, 2007 at 11:30 am #27989yParticipantquote mcMike:
Just try and remember that when it comes to setting prices if you ever decide to sell anything 😆
That is some nice looking work, not only that but not exactly simple peices either, as someone who has a lathe I can certainly say your being very modest.November 23, 2007 at 4:18 pm #27996voltar-1Participant
Mike, how do you fill the tank?November 23, 2007 at 4:39 pm #27998anthony266Keymaster
Eagerly waiting for some test reports….
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