power plentum and reg creep

You may not need to pop off the first few shots with the Huma but no guarantees because even Humas can creep too but it shouldn't be as bad and most often work perfectly as they should. If you are happy with your gen1 WC performance aside from having to pop off a few shots before doing any serious shooting I would just save money and leave it be. The gen1s tend to be more reliable than the newer ones FYI... YO!
 
I think he's asking if, all else being equal (creep amount, reg pressure, hst), would having a larger plenum mean more initial dry fire to drop the plenum pressure. In that case it would. The whole point is to have more regulated air volume to reduce the overall pressure drop in the plenum during the shot cycle. That improves efficiency but would obviously also require a couple more shots to bring it down to normal pressure levels in the event of creep.


 
I put a Huma on my Impact shortly after I got it as the FX reg rod had a flat spot in it when I received it and they took months to get a new one to me. Both regs are prone to creeping slightly but a shot or two after filling or the gun sitting idle for days usually takes care of it. I have installed Michal's plenum so larger volume and it still settles after a shot or two.
 
I think he's asking if, all else being equal (creep amount, reg pressure, hst), would having a larger plenum mean more initial dry fire to drop the plenum pressure. In that case it would. The whole point is to have more regulated air volume to reduce the overall pressure drop in the plenum during the shot cycle. That improves efficiency but would obviously also require a couple more shots to bring it down to normal pressure levels in the event of creep.


thanks Macros,

thats what i figure also. not sure if its coincidence or something else, but i replaced my stock FX reg because of creep with a Huma, and the results were exactly the same. i want more shots from my wildcat, so i am contemplating a plentum, but dont want to crck off 5 shots of air if i let it sit for a day or two.
 
I think he's asking if, all else being equal (creep amount, reg pressure, hst), would having a larger plenum mean more initial dry fire to drop the plenum pressure. In that case it would. The whole point is to have more regulated air volume to reduce the overall pressure drop in the plenum during the shot cycle. That improves efficiency but would obviously also require a couple more shots to bring it down to normal pressure levels in the event of creep.


thanks Macros,

thats what i figure also. not sure if its coincidence or something else, but i replaced my stock FX reg because of creep with a Huma, and the results were exactly the same. i want more shots from my wildcat, so i am contemplating a plentum, but dont want to crck off 5 shots of air if i let it sit for a day or two.

Then, lower the reg pressure or turn up the hammer spring a little more. Your hammer strike isn't balanced for the reg pressure your running. You can tune around the reg creep. 
 
what im asking is since i have to fire a few shots to burn out the creep, will having a larger plentum hold more of that reg creep air and require more shots to bring it to the regulated pressure since the plentum holds more regulated air.

Correct ... If using the same reg that creeps, having an increase in plenum size miens you now have more air that is at too high a pressure and therefor MORE SHOTS required to get stabilized.
 
what im asking is since i have to fire a few shots to burn out the creep, will having a larger plentum hold more of that reg creep air and require more shots to bring it to the regulated pressure since the plentum holds more regulated air.

Correct ... If using the same reg that creeps, having an increase in plenum size miens you now have more air that is at too high a pressure and therefor MORE SHOTS required to get stabilized.


But doesn't the rate of creep also have to be taken into account? Let's say the reg is set at 140 bar and over the course of 4 days, with a plenum of "x" size it, it will creep up to 150 bar. If you double the size of the plenum, assuming the same rate of increase wouldn't it take 8 days now to reach the 150bar? Or in the same 4 days only creep up to 145bar? If so then this would be true in the 8 days period, but in the 4 days period it would theoretically take the same # of shots? Twice as much air, but only 1/2 was much pressure increase?
 
I think he's asking if, all else being equal (creep amount, reg pressure, hst), would having a larger plenum mean more initial dry fire to drop the plenum pressure. In that case it would. The whole point is to have more regulated air volume to reduce the overall pressure drop in the plenum during the shot cycle. That improves efficiency but would obviously also require a couple more shots to bring it down to normal pressure levels in the event of creep.


thanks Macros,

thats what i figure also. not sure if its coincidence or something else, but i replaced my stock FX reg because of creep with a Huma, and the results were exactly the same. i want more shots from my wildcat, so i am contemplating a plentum, but dont want to crck off 5 shots of air if i let it sit for a day or two.

Then, lower the reg pressure or turn up the hammer spring a little more. Your hammer strike isn't balanced for the reg pressure your running. You can tune around the reg creep.

when i bought the Huma, i just guessed and set it for 135 bar. theni started the hammerspring screw flush to the back of the gun and turned it up watching my chrono each turn. when my speed slowed down i then reversed the process til i was just below my max speed at that reg setting.

i will probably skip the power plentum. i am happy with my tune other than needing to fire two blasts of air before my regged air is correct.
 
what im asking is since i have to fire a few shots to burn out the creep, will having a larger plentum hold more of that reg creep air and require more shots to bring it to the regulated pressure since the plentum holds more regulated air.

Correct ... If using the same reg that creeps, having an increase in plenum size miens you now have more air that is at too high a pressure and therefor MORE SHOTS required to get stabilized.


But doesn't the rate of creep also have to be taken into account? Let's say the reg is set at 140 bar and over the course of 4 days, with a plenum of "x" size it, it will creep up to 150 bar. If you double the size of the plenum, assuming the same rate of increase wouldn't it take 8 days now to reach the 150bar? Or in the same 4 days only creep up to 145bar? If so then this would be true in the 8 days period, but in the 4 days period it would theoretically take the same # of shots? Twice as much air, but only 1/2 was much pressure increase?



Not necessarily .... Creep is not a constant and one needs to understand WHY it finally stops and plenum pressure does not keep increasing ?

That reason is as the plenum pressure increases so is that pressure forcing the seat harder attempting to create a seal. At some point the seat pressure is sufficient and creep stops.

So the question & anwser actually becomes .... Based upon the rate of creep present a larger plenum would take longer to get to said pressure when creep stops. Such as Ninja regulators often exhibit, they creep immediately not settling for 30-45 seconds or more. With some seeming stable in the short term but creep in the long term. This too has a bearing on if creep or not is a problem ?

OP question being is if or not a larger plenum will need more purging shots to get equalized to a set pressure that is repeatable while actively shooting and that anwser is YES.


 
Another little snippet of regulators acting odd .... is that when a shot is taken one needs to understand the ONLY air being discharged is that of the plenum and regulator flow to replenish plenum contributes NOTHING to the shot .... Only replaces what what used !!



Oddity is this .... Some regulators need to feel / sense a fairly larger drop in pressure to open up and flow in replacement air. Where some regulator are very sensitive to a pressure drop and replenish effectively with less drop in plenum pressure.



AS YOU INCREASE plenum volume the average pressure drop from the shot becomes less and how the regulator deals with this matters when maintaining a stable pressure which equates to a stable velocity. NOT ALL REGULATORS ARE CREATED EQUAL