Crossfire Regs

[spantol]

That's cool. The offer stands, and--to clarify--is extended to the entire roundtable. I'm a big fan of your stated mission, and I'd like to support your current endeavor in any way that I can.

As I have a near-total lack of technical expertise, I'd say that limits me to donating equipment for testing.

[cledford]

Re: lots of questions....

Originally posted by Redkey
To have any useful data at least five crossfire regs would have to be tested. Testing just one is interesting... but you have no idea how it compares to the next one off the assembly line.

Originally posted by Redkey
How is the roundtable supposed to work?

Originally posted by Redkey
How is a test procedure decided on?

Originally posted by Redkey
Who is supposed to do all this testing?

Originally posted by Redkey
Will the owners of Crossfire Regs be willing to send them to a third party for testing?

Originally posted by Redkey
Would any of the manufactures of the equipment be willing provide samples for testing to a third party?

Originally posted by Redkey
How would the third party be decided on?

Originally posted by Redkey ]
How many people have the money, time or experience to put together a decent test setup?

Originally posted by Redkey
How will the quality of the third party data be verified?

Require that it adhere to the rules that ours will abide by.

Originally posted by Redkey
Where will the test procedures be documented? Will the data be posted somewhere or will the person running the tests just say that A was better than B?

Originally posted by Redkey ]
It's a nifty idea and if it works the way it's supposed to... vendors might not be so quick to make boastful statements they have not proven.

[cledford]

Gauge update...

I've been working with Winters on obtaining some high quality gauges for this project.

They are sending me samples of their spiral tube gauges. These aren't accurate enough or large enough (for video or pictures) for our needs so they are also working on finding us a Bourdon tube model.

The model that looks like it would work the best for us is their premium, 2.5" face, 0-1500psi, liquid-filled or dry model. The only problem at this point is that in the rest of the HPA industry they use 1/4NPT for pressures over 1000psi. We use 1/8NPT for everything in paintball and they don't have a 1/8NPT model readily available. They are looking at changing the input to 1/8 or providing a 1/4-1/8 adapter for us. I plan on getting one of each - liquid -filled and dry.

I've learned some cool things about gauges from this experience. On of the more interesting tidbits is that we can get the Bourdon tube gauges certified for accuracy which will be useful.

I going to throw together the ASA tester described in one of my previous post this weekend using a spiral tube gauge and see how it works. I want to wait until I get the good ones before really testing.

-Calvin

[314159]

Originally posted by nerobro
I'll call him today ;-)

i forgot to tell you i talked to the centerflag guy a little about it at the event. (he was also the guy that sold me my first paintball gun at fox river games ^_^).


about the idea of sending in used tanks to get a wider range of data, used regs vs new regs will probilly give you different data (broken in/amount of "luvin"....) =/. i also think that we might come into problems borrowing tanks from people.

i have an ideas to check the flow of a tank:

air america has a device to test regs w/co2 threads. you have a knob that controlls the flow that you dump the tank at, and a guage. because there should be a relitavley constant flow (up untill a point), the guage is not too picky as it's responce speed.
-fill up a tank to a given pressure
-set the tank to a given output
-start with a low flow rate of the dumping of the tank
-start a timer when you start dumping the tank controlling the flow, stop the timer when the tank's output drops out of a certain threshold (maby 10% of the output pressure). if the tank kept up, the tank pressure will be (10%) of the output pressure, record this time, THIS IS YOUR MEASUREMENT OF FLOW
-fill tank again, increase flow rate a little, repeat previous step. if the tank's output falls from (10%) of it's input before the tank has emptied, you have surpassed the maximum flow of the tank, use the lowest time obtained previously (with a tank pressure of (10%) of it's output, an "empty" tank). THIS IS YOUR MEASUREMENT OF MAXIMUM FLOW.

you can call this number something like cc*psi/seconds

[Redkey]

home brew testing

**ooppss.. this sat open too long and belongs up a couple messages.

The hardest part of this is coming up with test methods than anyone can do at home. Every thing I dream up uses moderately high speed data collection, strain gages, optical sensors and pressure transducers.

For those doing testing at home there should be a list of suggested equipment. If we say that XXX pressure gauge from YYY manufacturer should be used for all home brew tests between 100 and 500 psi it might with the consistancy of the data.

Also, speaking of pressure gauges, there should be some general guide lines for using the proper gauge. For my work we use a 10% rule of thumb... ie a 100 lb load cell should not measure anything less than 10 lbs. This way we would avoid having people measuring 60 psi with a 3,000 psi gauge.

I'm more than happy to assist anyone with their test procedures and give them suggestions on how to make sure their test system is doing what they think it is, does anyone know what a MSA is?. I'm also willing to perform statistical analysis on any data that people collect and show them how to present the data in a semi-professional manner.

Rebuts to any report/data could be submitted, answered and then added to the final report/data thread.

When I say "Third Party"... would a member of this group be willing to send their paintball gear to another member of the group to be tested?

Fun stuff, thank *you* for putting effort into this.

[Redkey]

Nice simple idea...

Originally posted by 314159


-start a timer when you start dumping the tank controlling the flow, stop the timer when the tank's output drops out of a certain threshold (maby 10% of the output pressure). if the tank kept up, the tank pressure will be (10%) of the output pressure, record this time, THIS IS YOUR MEASUREMENT OF FLOW

At the end of this test the tank pressure should be 90% of the output pressure. Say your output pressure is 300 psi... when this pressure drops 10% the test is ended. 300 psi - 10% (30 psi) = 270 psi = approx residual pressure in tank.

Originally posted by 314159


-fill tank again, increase flow rate a little, repeat previous step. if the tank's output falls from (10%) of it's input before the tank has emptied, you have surpassed the maximum flow of the tank, use the lowest time obtained previously (with a tank pressure of (10%) of it's output, an "empty" tank). THIS IS YOUR MEASUREMENT OF MAXIMUM FLOW.

you can call this number something like cc*psi/seconds

Dumping this much air from a tank will cause it to cool... will that be enough to impact the data? I don't know.

You'll need a way to measure the flow rates at each setting so that you can repeat the test several times and average the results. The problem with controlling the flow with a valve is that you really have no way to make sure that the flow rate is the same as when you ran the tests last week.

for your units...
seconds from stopwatch
psi from output pressure?
cc from?

what about doing the test slightly different....
How about just dumping air from the tank for 10 seconds and then measure the remaining pressure? You'll have to have a good gauge on the tank to get accurate readings. You'll also need an above average valve system that opens 100% almost instantly. Regs with more flow will dump more air and show a larger pressure drop.

just a thought.

[314159]

Originally posted by Redkey
what about doing the test slightly different....
How about just dumping air from the tank for 10 seconds and then measure the remaining pressure? You'll have to have a good gauge on the tank to get accurate readings. You'll also need an above average valve system that opens 100% almost instantly. Regs with more flow will dump more air and show a larger pressure drop.

unless a tank can provide pressure close to the regulated pressure it is supposed to kick out, the reg is not dooing it's job. i think that the test should be for flow rate within a certain bounds of the pressure that it is supposed to regulate.

[Pand0ra]

[Redkey]

Originally posted by Pand0ra
Why don't u simply use a ... flowmeter?

Good accurate flow meters that can handle 300 to 800 psi are not cheap.

Originally posted by Pand0ra

I don't see why you need to control the flow. The regulator works always at it's fastest speed when it tries to correct a drop of pressure at the output.
An output pressure at 0psi is just the worst case.

By controlling the flow you should be able to determine the point at which the reg cannot keep up.

Originally posted by Pand0ra

Anyways, you can't determine an output pressure once for all. It changes too much with the configuration of the marker, the rate of fire, the size of the fittings, and so on. Even the temperature will influence the result.

this is true... that's why the tests should be done off gun. There are so many possible combinations of parts on markers that it would be impossible to extract meaningfull data if everyone tested their own gun.

All we are doing is looking at the regs ability to provide a certain amount of airflow at a certain pressure level. It doesn't matter if the gun is a spyder, a sandridge or a pneumatic nailer. Having said that... is the regs static airflow (constant stream of air) the same as it's dynamic airflow (on off on off on off)?

Originally posted by Pand0ra

Edit: Get rid of those jauges. Remove them, and put at the place a good pressure sensor. At least this way the measurement will be reliable (and not in the range of 10-20% of precision).

true again. although, pressure transducers are expensive and require additional hardware to collect the data. The transducers also need to be calibrated otherwise you'll have no idea if you have 1% or 30% error. The reason why gauges are being discussed is that they are easy to use and fairly affordable. If people want to run their own teststhey probably don't want to spend a wad of cash on equipment. Only engineering geek losers like me get enjoyment out of dropping hundreds of dollars to build their own DAQ system.

[AGD]

Guys,

Good to see that this is moving forward. I'm sure once you bake the bread everyone will be here to eat it. Since we only have a few people officially on the board I would like to invite Redkey and 3124 to join. Please post your pics and bio in the classic thread for it to be official. After you guys post I will close the roundtable membership. Anyone not posted is out.

Thanks!!

AGD

[Pand0ra]

Originally posted by Redkey

Having said that... is the regs static airflow (constant stream of air) the same as it's dynamic airflow (on off on off on off)?

Depends on the rate at which you cut the airflow.
The lower the frequency, the closer you'll be to the static airflow (assuming you keep the cyclic ratio constant).

Only engineering geek losers like me get enjoyment out of dropping hundreds of dollars to build their own DAQ system.

Oh! You too?

@++

[athomas]

A couple of suggestions:

Use a controlled chamber size for the area to be recharged. Use a 1 cubic inch and/or a 2 cubic inch storage chamber. Feed the storage chamber from the bottle to be tested. Monitor the pressure in the chamber using a good electronic pressure transducer hooked to a computer. Control an exhaust valve in the storage chamber using the same computer.

Now, we know the exact size of the chamber to be recharged. We can control the time between controlled pressure dumps. We can measure the rate of recharge using the sensor. We could even control the output flow of the chamber to see at which point the tank can no longer keep up. If needed, we could also control a valve at the input to the chamber to control the exact time required to totally charge a chamber of a known size from nothing to a controlled pressure.

The computer can simulate the firing of a paintball gun by opening and closing the chamber. We would then have a more controlled environment than relying on a paintball gun that we know may affect the results.

[magnj]

i know im buting in the middle here but isnt 11 bps not so fast. If a tank drops off past 11 bps thats not too amaixing is it? Maybe for a screw in it is? also is AGD helping you at all, are they giving you any hardware to use?

[ES13Raven]

Has anyone done any further testing?

[cledford]

Sorry,

Not recently. I broke my wrist and it currently has 5 pins in it. I can barely hold anything in my left hand, so it is impossible to consider pursuing anything until I can use it again. The requirements to actually use tools (to remove fittings, etc.) precludes me from working on this right now. I am slightly surprised that other round table members haven't continued to run with this...

-Calvin