Based both on the calculations and my test trials, you will need to use nested pairs (or heavier singles) to achieve pressures in that range.
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BARGAIN ALERT WITH LINK
- Thread starter SteveV
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So a 36 Belleville nested stack like so:
))(())(())(())(())(())(())(())(())((((
required a little bit of preload to get screwed down and the regulator was passing air up to 1650 psi, where my little guppy bottle equalized. So I'm uncertain whether I found a stack that will do above 1500 or if it is flat and just letting everything through. Didn't have time to pull out my hand pump and keep pumping, so I'll do further testing when I can.
))(())(())(())(())(())(())(())(())((((
required a little bit of preload to get screwed down and the regulator was passing air up to 1650 psi, where my little guppy bottle equalized. So I'm uncertain whether I found a stack that will do above 1500 or if it is flat and just letting everything through. Didn't have time to pull out my hand pump and keep pumping, so I'll do further testing when I can.
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When you find the proper stack height, it should work nicely at 1600 - 1700 psi because the Bellevilles will be at about two-thirds of their rating. Like you, I'm not real optimistic the burst disk will hold though.
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If someday you wanted to do a write up on the math you use to calculate this stuff, it would be a very interesting read. I've been taking the working load and max load numbers, along with the estimates you've been making, to try and reverse engineer the math you're doing. But it's not going well.
My brain does IT work, not math apparently.Upvote 0
For a regulator of this type, it's just the difference in the force acting on the large end of the piston vs the force acting on the small end:
View attachment 322065
A copy of the spreadsheet:
Dropbox
www.dropbox.com
Amazing, thank you!
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Okay, update! 32 Bellevilles stacked like below is good for 1800 psi in my regulator.
))(())(())(())(())(())(())(())((
))(())(())(())(())(())(())(())((
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Well done! Took 3 packs of Bellevilles to get there but still better off cost-wise than those pricey 0.030" thick ones.
What is your approach for the burst disk?
And do you mind if I share your findings over on the GTA thread?
What is your approach for the burst disk?
And do you mind if I share your findings over on the GTA thread?
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Don't mind at all! I currently have one of the 7.5k burst disks in place *for testing purposes only*. I haven't figured out what I'm going to do long term. Blows my mind that we have zero burst disk options between 1.8k (which are really like 1.5k) and 5k (which are marked 3k). Absolutely stupid.
I've got this second tank that I'm messing with. I want to run it at 1400-1450 and it will go on my wife's bullpup Prod as a dual regulator setup. I picked up a carbide bur and a little desktop vice. I will take another stab at those blasted washers.
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There might be some trouble in paradise. I put the bottle that I measured having an 1800 psi output onto my bottled Prod and the results are confusing. My bottled Prod does 13 fpe on a regulator with a known output of 1450 psi. It did 9 fpe with the factory FS bottle, which is presumably near 850 psi. When I attached the 1800 psi bottle, I am getting 10 fpe now. If the regulator failed for some reason, I would think that I would be getting more power, since I have a .18" TP and stock Prods do 13-14 fpe. The shots are very consistent with a sub-20 fps spread over 15 shot string, so it's definitely regulating. Maybe my hammer spring tension is just to low for 1800 psi?
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My thought exactly. If the hammer spring tension was adjusted to not waste air when the reg was at 1450psi, the hammer strike is insufficient for the new 1800psi setpoint.
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When I've run into that problem, my answer was to make it myself. How I approached it:
need advice on a AR build - Airguns & Guns Forum
need advice on a AR build, Air guns, Airgun Forum
www.gatewaytoairguns.org
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Need a sanity check. Does nesting washers increase setpoint if there are still single washers in the stack? I.e., would ))()()(())(( have a higher sepoint than ))()()(( or will the single washers flatten and negate the nested pairs?
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Adding singles in a stack comprised mostly of nested pairs, for the most part the singles will just squeeze flat and act as simple flat washers. So in that sense they do not negate anything about the operation of the nested pairs, but do be aware that depending on how the singles are placed, they can potentially become inverted and damaged. Turned inside out, so to speak. An example being the guy in the middle here )) ( ))
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I'm running 1800 psi in the regulator for my prod I installed 3 k burst disk in the one spot the 1.8 k only last a couple fills and scared the heck out of when it popped lol. I put several different stacks together in different regulators when I was building my bottle disco which I don't really use any more running 14 gr pellets at 730 fps mouse fart quiet I may pull the prod apart and see if it's got a lighter hammer in it I bought it used and found a tiny hill transfer port in place couldn't get over 530 fps with it
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I've also thought about running it so the reg would just put out 3000 psi to the gun and tune it as if it wasn't regulated at all but so far I'm happy with what it is at if and thing I may change the hammer and lengthen the stroke to see if I can get to 20 fpe with 14 gr pellets nothing to excessive I want to keep a decent shot count to
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I'd like to run my second bottle as a straight 3K for my wife's regulated Prod, but I wasn't able to get answer from FS on whether the bonnet is rated for 3k.
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I have a air venturi reg that was set to 2900 psi that came on a carbon fiber bottle that I bought for a buddy bottle from pyramid air it looks Identical to the ninjas as far internals and thickness
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