[Silyputy]

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!

[andrewthewookie]

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.

This post has been edited by andrewthewookie: 07 February 2013 - 01:12 AM

[Silyputy]

andrewthewookie, on 07 February 2013 - 01:11 AM, said:

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?

[ktap]

andrewthewookie, on 07 February 2013 - 01:11 AM, said:

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.

This post has been edited by ktap: 07 February 2013 - 01:28 AM

[Law]

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

[slinkyaroo]

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.

[andrewthewookie]

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

[brycelarson]

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.

[Silyputy]

brycelarson, on 24 February 2013 - 11:42 AM, said:

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!

[cockerpunk]

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.

This post has been edited by cockerpunk: 25 February 2013 - 03:14 PM

[andrewthewookie]

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

[cockerpunk]

andrewthewookie, on 25 February 2013 - 03:53 PM, said:

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

oh shut up, i labeled my axis

[dosh]

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.

[Troy]

dosh, on 24 March 2013 - 04:55 PM, said:

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.

[brycelarson]

dosh, on 24 March 2013 - 04:55 PM, said:

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.

[dosh]

brycelarson, on 25 March 2013 - 07:47 AM, said:

dosh, on 24 March 2013 - 04:55 PM, said:

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.

This post has been edited by dosh: 25 March 2013 - 12:12 PM

[cockerpunk]

dosh, on 25 March 2013 - 11:56 AM, said:

brycelarson, on 25 March 2013 - 07:47 AM, said:

dosh, on 24 March 2013 - 04:55 PM, said:

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?

[dosh]

cockerpunk, on 25 March 2013 - 01:22 PM, said:

dosh, on 25 March 2013 - 11:56 AM, said:

brycelarson, on 25 March 2013 - 07:47 AM, said:

dosh, on 24 March 2013 - 04:55 PM, said:

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.

This post has been edited by dosh: 25 March 2013 - 03:08 PM

[cockerpunk]

dosh, on 25 March 2013 - 02:19 PM, said:

cockerpunk, on 25 March 2013 - 01:22 PM, said:

dosh, on 25 March 2013 - 11:56 AM, said:

brycelarson, on 25 March 2013 - 07:47 AM, said:

dosh, on 24 March 2013 - 04:55 PM, said:

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.

[brycelarson]

cockerpunk, on 25 March 2013 - 02:45 PM, said:

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.