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#1 Silyputy

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Posted 07 February 2013 - 12:57 AM

ok so since i got into paintball i have been wondering about this now i know popits are more efficient than spools. but i dont get why. this is just how i see it i own an etek 4 and every time i shoot it air shoots out of the back and with a spool its all enclosed so, why are popits more efficient? i just dont get it. anyone have a pic or something that explains how they each work. that might help....??? Thanks!

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#2 andrewthewookie

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Posted 07 February 2013 - 01:11 AM

In general, some poppets are more efficient than spools, however there are a few spools that are very efficient as well. Basically though, the reason poppets were more efficient to begin with is just an inherent part of their design. When you open a valve faster, the air is able to pass through that valve more efficiently than if it opened more slowly, so the guns with a faster acting valve would just have a better chance to be more efficient.

Edited by andrewthewookie, 07 February 2013 - 01:12 AM.

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#3 Silyputy

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Posted 07 February 2013 - 01:23 AM

In general, some poppets are more efficient than spools, however there are a few spools that are very efficient as well. Basically though, the reason poppets were more efficient to begin with is just an inherent part of their design. When you open a valve faster, the air is able to pass through that valve more efficiently than if it opened more slowly, so the guns with a faster acting valve would just have a better chance to be more efficient.

so that would then go along with the "poppets are less smooth" because its moving faster? or am i taking it the wrong way?

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#4 ktap

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Posted 07 February 2013 - 01:28 AM

In general, some poppets are more efficient than spools, however there are a few spools that are very efficient as well. Basically though, the reason poppets were more efficient to begin with is just an inherent part of their design. When you open a valve faster, the air is able to pass through that valve more efficiently than if it opened more slowly, so the guns with a faster acting valve would just have a better chance to be more efficient.


To clarify this; a ball takes (iirc) ~6ms to accelerate and leave the gun. So theoretically you would want your valve to deliver all the air needed in that time or faster. However you need to apply the necessary force to open the valve itself, as well as cycle the gun. Due to the inherent qualities of the poppet design, the valve can be opened and closed faster than a spool, resulting in less wasted air. Google ZDSPB animations, they will help a lot.

Edited by ktap, 07 February 2013 - 01:28 AM.

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#5 Law

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Posted 24 February 2013 - 08:02 AM

Are either the poppet or spool design more consistent than the other, or is that mostly about the regulator?

#6 slinkyaroo

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Posted 24 February 2013 - 09:10 AM

A poppit takes less air to move a small ram a short distance than to fill a bolt chamber in a spoolie to move the bolt (hence top hat mods) Remember that you got to fill it to return it too.

#7 andrewthewookie

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Posted 24 February 2013 - 11:13 AM

The consistency of a gun pretty much comes down to the regulator.

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#8 brycelarson

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Posted 24 February 2013 - 11:42 AM

The term I like to use is "valve resolution". Think of it this way - the poppet is a Hi-Def valve. It acts quickly so can be fully opened and closed in a very short, time controlled way. The spool has a longer articulation and does it more slowly. It's a lower resolution valve - meaning you don't have as precise control.

#9 Silyputy

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Posted 24 February 2013 - 07:49 PM

The term I like to use is "valve resolution". Think of it this way - the poppet is a Hi-Def valve. It acts quickly so can be fully opened and closed in a very short, time controlled way. The spool has a longer articulation and does it more slowly. It's a lower resolution valve - meaning you don't have as precise control.

ok i kind of get it a bit more now after reading some of the other comments i had not read yet. thanks!

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#10 cockerpunk

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Posted 25 February 2013 - 03:07 PM

pretty lame way to explain it, but here is a graphical way to think about it. simply put, the poppit is able to open much faster, and thus put more air behind the ball quicker. ususally they close faster too. the band aide to slow closing in a spool is to seal off the dump chamber, but it still is worse on the tail end of the cycle too.

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Edited by cockerpunk, 25 February 2013 - 03:14 PM.

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#11 andrewthewookie

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Posted 25 February 2013 - 03:53 PM

No units on your axes? I'm disappointed in you.

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#12 cockerpunk

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Posted 25 February 2013 - 04:37 PM

No units on your axes? I'm disappointed in you.


oh shut up, i labeled my axis
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And yes, Gordon is the sexiest manifestation of "to the front."


#13 dosh

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Posted 24 March 2013 - 04:55 PM

Keep in mind I'm looking at this entirely from an electro standpoint, poppets on a mechanical should act differently.

The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.

On a poppet you have a hammer solidly attached to a ram. The hammer hits the valve then the ram retracts it closing the valve. The valves open/closed position is directly affected by it's contact with the hammer.

But in either situation you have to depend on the speed of the ram to open and close the pathway for the air. The only difference I can see is the valve and air pressing against the poppet helping to accelerate the ram on its return.

#14 Troy

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Posted 24 March 2013 - 09:08 PM

Keep in mind I'm looking at this entirely from an electro standpoint, poppets on a mechanical should act differently.

The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.

On a poppet you have a hammer solidly attached to a ram. The hammer hits the valve then the ram retracts it closing the valve. The valves open/closed position is directly affected by it's contact with the hammer.

But in either situation you have to depend on the speed of the ram to open and close the pathway for the air. The only difference I can see is the valve and air pressing against the poppet helping to accelerate the ram on its return.


Thar's ur problem!

The ram doesn't close a poppet valve. The momentum of the ram opens the valve, when the momentum is all used up, the spring in the valve closes it.
\m/

#15 brycelarson

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Posted 25 March 2013 - 07:47 AM

The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.

#16 dosh

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Posted 25 March 2013 - 11:56 AM


The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.



Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.

Edited by dosh, 25 March 2013 - 12:12 PM.


#17 cockerpunk

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Posted 25 March 2013 - 01:22 PM



The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.



Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.


sure, if you can move a spool valve as fast and hard a poppit, it will run like a poppit.

so what?
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#18 dosh

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Posted 25 March 2013 - 02:19 PM




The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.





Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.


sure, if you can move a spool valve as fast and hard a poppit, it will run like a poppit.

so what?


So if there's a current deficiency in spool designs that can be cured then you can build a better mouse trap. You can get an equal or lower reciprocating mass out of a spool so getting the speed isn't a problem.

Edited by dosh, 25 March 2013 - 03:08 PM.


#19 cockerpunk

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Posted 25 March 2013 - 02:45 PM





The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.





Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.


sure, if you can move a spool valve as fast and hard a poppit, it will run like a poppit.

so what?


So if there's a current deficiency in spool designs that can be cured then you can build a better mouse trap. You can get an equal or lower reciprocating mass out of a spool so getting the speed isn't a problem. There's a path to building a better mousetrap here.


not really,

so if you make a spool shoot like a poppit, it will have the same type of performance as a poppit (ie kick), so why didn't you just shoot/design a poppit in the first place?

also, the reverse is true, if you slow down a poppit system you can make it operate as inefficiently as a spool, and be much much smoother the traditional poppits, but why would you? it makes no sense.
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And yes, Gordon is the sexiest manifestation of "to the front."


#20 brycelarson

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Posted 25 March 2013 - 02:49 PM

so if you make a spool shoot like a poppit, it will have the same type of performance as a poppit (ie kick), so why didn't you just shoot/design a poppit in the first place?


actually assuming we're talking about a spool scaled like most modern spools we would be talking about a huge increase in kick - since there's so much moving mass when talking about a spool vs a rammer.

#21 dosh

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Posted 25 March 2013 - 07:14 PM






The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.





Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.


sure, if you can move a spool valve as fast and hard a poppit, it will run like a poppit.

so what?


So if there's a current deficiency in spool designs that can be cured then you can build a better mouse trap. You can get an equal or lower reciprocating mass out of a spool so getting the speed isn't a problem. There's a path to building a better mousetrap here.


not really,

so if you make a spool shoot like a poppit, it will have the same type of performance as a poppit (ie kick), so why didn't you just shoot/design a poppit in the first place?

also, the reverse is true, if you slow down a poppit system you can make it operate as inefficiently as a spool, and be much much smoother the traditional poppits, but why would you? it makes no sense.


What if you could make a drop in assembly that gave you the efficency of a poppet without increasing kick? Lighten the bolt, massage how it seals, creative chamfering... I think this might be doable. There is no absolute that says a spool has to be either hard kicking or ineffecient.

#22 dosh

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Posted 25 March 2013 - 07:23 PM


so if you make a spool shoot like a poppit, it will have the same type of performance as a poppit (ie kick), so why didn't you just shoot/design a poppit in the first place?


actually assuming we're talking about a spool scaled like most modern spools we would be talking about a huge increase in kick - since there's so much moving mass when talking about a spool vs a rammer.



Not really. Think about what an Ego is moving. Two chunks of stainless and a peice of delrin compared to an aluminum shaft in a spool gun. The delrin is the largest piece, and it's a little more than half the weight of aluminum per cubic inch, but the stainless is just under three times the weight. Also the delrin is thick walled. There's alot of mass being moved there in comparison to a spool guns bolt, even without looking at alternative materials or design to remove material.

Mass x velocity=force. You can lighten the bolt and speed it up while keeping the same force so the amount pf kick stays the same.

#23 andrewthewookie

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Posted 25 March 2013 - 07:24 PM

What if you could make a drop in assembly that gave you the efficency of a poppet without increasing kick? Lighten the bolt, massage how it seals, creative chamfering... I think this might be doable. There is no absolute that says a spool has to be either hard kicking or ineffecient.

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#24 cockerpunk

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Posted 25 March 2013 - 07:49 PM







The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.





Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.


sure, if you can move a spool valve as fast and hard a poppit, it will run like a poppit.

so what?


So if there's a current deficiency in spool designs that can be cured then you can build a better mouse trap. You can get an equal or lower reciprocating mass out of a spool so getting the speed isn't a problem. There's a path to building a better mousetrap here.


not really,

so if you make a spool shoot like a poppit, it will have the same type of performance as a poppit (ie kick), so why didn't you just shoot/design a poppit in the first place?

also, the reverse is true, if you slow down a poppit system you can make it operate as inefficiently as a spool, and be much much smoother the traditional poppits, but why would you? it makes no sense.


What if you could make a drop in assembly that gave you the efficency of a poppet without increasing kick? Lighten the bolt, massage how it seals, creative chamfering... I think this might be doable. There is no absolute that says a spool has to be either hard kicking or ineffecient.


it does if the forces needed to operate the parts at the required speed/force mean you have that kind of kick.

the best idea is to combine the two systems, alla pressure controled poppits or tweak the systems, like the new LV1 ego, or the above mentioned shocker eigenbolt, which helps the dynamics of the shocker valve.
The ultimate truth in paintball is that the interaction between the gun and the player is far and away the largest factor in accuracy, consistency, and reliability.

And yes, Gordon is the sexiest manifestation of "to the front."


#25 brycelarson

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Posted 26 March 2013 - 08:21 AM

Mass x velocity=force. You can lighten the bolt and speed it up while keeping the same force so the amount pf kick stays the same.


Kinetic Energy = 1/2m*v^2

The speed matters more than the mass.

So, the short answer is that it's design dependent. Here's an example - let's say that a spool has twice the mass but moves half as fast. Let's say 10g for the poppet and 20g for the spool. If the spool moves 100 m/s and the poppet moves 200 m/s then the force calculations are:

Spool E = .5*.02*100^2 or 100 Joules
Poppet E = .5*.01*200^2 or 200 Joules

So, when doubling the speed and halving the mass the energy involved is doubled.

Spools are smooth due to slow movement.

#26 cockerpunk

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Posted 26 March 2013 - 12:14 PM

well there are also impact issues, the poppit tends to hit a harder stop on each end (or at least the front, valve, end), but a spool has to hit a stop on each end too, so again, there isn't much to play with there. so when you talk about speeding up a spool bolt to get the valve open faster, you eventually have to stop it again (when the bolt is closed), requiring some kind of stop.
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#27 dosh

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Posted 27 March 2013 - 12:00 PM

[quote name='cockerpunk' timestamp='1364318053' post='3182576']
well there are also impact issues, the poppit tends to hit a harder stop on each end (or at least the front, valve, end), but a spool has to hit a stop on each end too, so again, there isn't much to play with there. so when you talk about speeding up a spool bolt to get the valve open faster, you eventually have to stop it again (when the bolt is closed), requiring some kind of stop.


I've been thinking about what you guys have been saying, and without getting actual weights and speeds it's hard to come to a conclusion. I pulled the bolt out of my Ion and the bolt and rammer out of my Etek3. I'd say off hand they should be fairly representative of both families.

The Ion bolt felt just a little lighter then the Etek assembly, not much, but perceptible. That makes sense when you think about what both have to do. The spool valve just has to slide back and forth. The poppet has to transfer energy at the end of it's stroke to overcome the spring and air pressure against the cup seal. The poppet needs to weigh more and move faster.

If you guys have a source for weights and cycle speeds you can share I'd appreciate it. I've been trying to find something solid and it's been a fruitless search.

#28 benzy2

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Posted 09 April 2013 - 11:34 PM

While speed is more important, you could find a happy middle ground. If you equal poppet marker speed but use 1/3 the mass, you'll end up with 1/3 the energy. If speed is a big key to efficiency, running something like an eigenbolt or an L7 type ultra light bolt should keep kick at a fraction of an equally speedy poppet type marker with ram, bolt, and bolt pin all being tossed around. From there, use some of the better design features to quickly close the valve and you ought to see nearly equal efficiency numbers while still being a far softer cycle than a typical poppet.

#29 Punisher068

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Posted 10 April 2013 - 01:49 AM

Wonder how a closed bolt spool valve would fit into this question?
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#30 Danny D

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Posted 14 April 2013 - 02:13 PM


well there are also impact issues, the poppit tends to hit a harder stop on each end (or at least the front, valve, end), but a spool has to hit a stop on each end too, so again, there isn't much to play with there. so when you talk about speeding up a spool bolt to get the valve open faster, you eventually have to stop it again (when the bolt is closed), requiring some kind of stop.


I've been thinking about what you guys have been saying, and without getting actual weights and speeds it's hard to come to a conclusion. I pulled the bolt out of my Ion and the bolt and rammer out of my Etek3. I'd say off hand they should be fairly representative of both families.

The Ion bolt felt just a little lighter then the Etek assembly, not much, but perceptible. That makes sense when you think about what both have to do. The spool valve just has to slide back and forth. The poppet has to transfer energy at the end of it's stroke to overcome the spring and air pressure against the cup seal. The poppet needs to weigh more and move faster.

If you guys have a source for weights and cycle speeds you can share I'd appreciate it. I've been trying to find something solid and it's been a fruitless search.


I cant speak for the etek, but the Ions bolt weight has nothing to do with the actuation speed. I have tried the L7 bolt, stock ion, firebolt and redz bolt with several variables. The only one I found to be significant enough to warrant its price is the QEV in terms of bolt speed.

The numbers:

Critical dwell values with QEV:
Stock - 8ms
Firebolt - 8ms
Red - 8ms
L7 - 7ms.

The only difference is 1ms with the L7. Compare that to the 15-20ms difference that a qev provides, It is clear that bolt weight is of minimal importance, and instead it is the exhaust that determines the speed of the bolt.

#31 Broccolidwarf

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Posted 23 April 2013 - 09:06 AM








The whole "poppets are faster" makes no sense. On both of them the amount of time the valve is open is dependent on where the open point is on the rams stroke. On the spool you have a stem clearing an o-ring which allows the air to flow down the bolt. The time from open to close depends on how fast the stem is moving past the o-ring.


actually poppets being faster makes a ton of sense. How far does a spool valve move to open the valve? At what speed? How how far and fast does a poppet move?

The answers are: along distance, slowly and a short distance, quickly.

The poppet takes less time to move from a closed to fully open position and less time from an open to a fully closed position. Thus, better valve resolution and more efficiency.





Then the problem isn't with the spool valve. The problem is with the engineer and where he is placing the open/close position in the rams stroke, and ram speed. There isn't any reason why the a spool can't have as good of a resolution as a poppet.

If we have two guns with the ram traveling at the same speed on both the forward and return stroke, and both are moving, lets say, 1/8 of an inch past where the seal is going to break, then both will open and close at the same time. Fully open for the poppet will be when the cup seal is at it's max travel from the valve guide, fully open for the spool is when the sealing surface has lost tangent with the o-ring, moved enough to clear the radius, and whatever material is forming the wall of the o-ring groove. You can do that in the same amount of space as a poppet, and since the gas doesn't have to hook three 90* turns you could shorten the dwell below the poppet valve.


sure, if you can move a spool valve as fast and hard a poppit, it will run like a poppit.

so what?


So if there's a current deficiency in spool designs that can be cured then you can build a better mouse trap. You can get an equal or lower reciprocating mass out of a spool so getting the speed isn't a problem. There's a path to building a better mousetrap here.


not really,

so if you make a spool shoot like a poppit, it will have the same type of performance as a poppit (ie kick), so why didn't you just shoot/design a poppit in the first place?

also, the reverse is true, if you slow down a poppit system you can make it operate as inefficiently as a spool, and be much much smoother the traditional poppits, but why would you? it makes no sense.


What if you could make a drop in assembly that gave you the efficency of a poppet without increasing kick? Lighten the bolt, massage how it seals, creative chamfering... I think this might be doable. There is no absolute that says a spool has to be either hard kicking or ineffecient.


it does if the forces needed to operate the parts at the required speed/force mean you have that kind of kick.

the best idea is to combine the two systems, alla pressure controled poppits or tweak the systems, like the new LV1 ego, or the above mentioned shocker eigenbolt, which helps the dynamics of the shocker valve.


I just watched the efficiency test TechPB did on the LV1, which I must admit was pretty disappointing for a poppet (7 pods if I remember correctly?).

Am I correct in assuming the poor efficiency, is directly related to the lever design meaning it takes far longer to open and close the valve now?

- and.... if I am correct, how could the design be improved, while maintaining what appears to be a very smooth shot?

(btw, just to be clear, It is the first ever Ego I seriously considered purchasing.... because it is fantastic from an ergonomic perspective, and seems to shoot very smooth..... but I need better efficiency to be able to make that choice)

#32 andrewthewookie

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Posted 23 April 2013 - 11:29 AM

He was also using the heavier ram, and was probably overboring as well.

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#33 Cookybiscuit

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Posted 23 April 2013 - 03:19 PM

If you think about it efficiency tests are not really indicative of efficiency, stupid as it sounds. Take for example the fact that the SL8R got 14 pods, and I think the Victory got 7 too. It just seems like theres so many factors that go into it (other than the gun) that its pretty hard to create a standard.

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#34 Egomaniacal

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Posted 30 April 2013 - 01:52 PM

Am I correct in assuming the poor efficiency, is directly related to the lever design meaning it takes far longer to open and close the valve now?

- and.... if I am correct, how could the design be improved, while maintaining what appears to be a very smooth shot?

(btw, just to be clear, It is the first ever Ego I seriously considered purchasing.... because it is fantastic from an ergonomic perspective, and seems to shoot very smooth..... but I need better efficiency to be able to make that choice)


The LPR on the LV1 is going to have a significant impact on efficiency (Jack has told me via PM that the LPR on the LV1 actually has an adjustment range). By tweaking the LPR, proper ram choice and dwell, I have little doubt it can be made quite efficient.
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#35 crich775

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Posted 11 June 2013 - 12:29 PM

When it comes down to it in my way of thinking it is mostly about the tuning in the end. I can run my ego with a very low pressure on my LPR and a long dwell to partially engage the valve and stretch the valve engagement time and it will smooth it out while losing efficiency, just as I can lengthen the bolt guide on my shocker to shorten the mechanical bolt dwell and run it at a higher pressure and low solenoid dwell to get better efficiency.
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#36 Billy Badass-RPF

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Posted 12 June 2013 - 12:33 PM

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#37 pShore

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Posted 13 June 2013 - 09:49 AM


Mass x velocity=force. You can lighten the bolt and speed it up while keeping the same force so the amount pf kick stays the same.


Kinetic Energy = 1/2m*v^2

The speed matters more than the mass.

So, the short answer is that it's design dependent. Here's an example - let's say that a spool has twice the mass but moves half as fast. Let's say 10g for the poppet and 20g for the spool. If the spool moves 100 m/s and the poppet moves 200 m/s then the force calculations are:

Spool E = .5*.02*100^2 or 100 Joules
Poppet E = .5*.01*200^2 or 200 Joules

So, when doubling the speed and halving the mass the energy involved is doubled.

Spools are smooth due to slow movement.



Um, I think your use of kinetic energy is a bit misguided... I believe momentum ( p = mv) is more appropriate for a situation such as this.
Or at F = ma... if you wanna talk about muscle strain to keep your gun stationary :D

Anyway, consider the following poorly thought out rambling... (i really haven't drawn any of this out and am just spilling some thoughts on a page, and yes I'll refer to a simple blow back design to exemplify momentum shifts):

I imagine that recoil forces that you are trying to compensate for with your muskels does come from the momentum contribution of accelerating the paintball, and from creating the air pressure differential at the tip of the barrel (which may logically be decreased by porting? applies symmetrical pressures in self-opposing directions around the barrel?).

But it's not just momentum we are talking about... it's perceived recoil -- force on the gun that must be opposed by your massive burly arm muscles (which are squarely anchored by that over-sized beer gut) in order to prevent the gun from accelerating. This is why a loose grip is often desired, as a straight-back recoil wouldn't throw off aim and avoids fatigue caused by a misguided attempt to keep the gun stationary. The point where this kinda falls apart is when we consider how we hold the marker (creates a pivot point), confounded by a shift in the center of mass of the marker... when the internal parts retract following a shot, the front of the gun is suddenly a ever so slightly lighter, further promoting muzzle raise.

Due to the way our markers generally work (and i'm not familiar with many... just blowbacks, cockers, mags, bob long vice, bob long marq), they acceleration of internal parts is relatively slower than the rates of deceleration (Yay! F=ma). Assuming the marker is stationary following the prefire low-acceleration phase (because we are super strong and can oppose this measly force!), rapid deceleration of the forward moving internal parts against the marker body should cause forward acceleration with the momentum shift (cuz we are maybe not that strong...). However, at that very moment an air pressure differential is created and a ball is accelerated...these forces are in opposition to the forward lurching of the gun...so we don't notice it (you can experience sans air pressure compensation by pulling the trigger of a Spyder that isn't aired up, and make the air pressure contribution super dramatic by firing an aired-up gun with no balls held directly against a wall). However, post shot, there is a second momentum shift experienced wherein parts are moving backward and are again abruptly decelerated... however this time it is adding additional rearward momentum beyond that contributed by the pressure/paintball.

But cycling at 12 bps raises an opportunity to balance all this crap! In an ideal situation, with such high frequencies, the net rearward momentum of a paintball shot should be able to be compensated for by a velocity differential of forward and rearward momentum of the internal parts during a single cycle.

In other words... at high enough cycle rates, we can assume that all three events occur simultaneously!

Then, balance the equation... (absolute values)

(rearward force due to air + acceleration of paintball) + (Rearward force due to momentum shift from post-shot internal parts) = (Force imparted by forward momentum shift of internal parts, pre-fire)

wait... maybe that doesn't make sense...

Whatever. The recoil is so small it shouldn't matter anyway, so long as your grip isn't wicked tight and you aren't creating a hinge-point with your form (hence holding your gun with two hands)




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