Carbon fiber tank question

I own an inexpensive but functional and convenient $160 compressor from Amazon (https://a.co/d/8sHtOTR). I use it to fill my PCP rifles at my gun club. It’s LOUD even though it is a gun club and folks are shooting some loud rounds! I now see, however, what an advantage a carbon fiber fill tank would offer. I will study the issue so as to get other questions answered on my own but for now I would welcome responses to one question, please:

Can these modest compressors fill an Air Venturi tank without overheating or breaking due to the amount of air the tanks require? Or are professional sources - like “scuba shops” - really the only safe way to fill them? Thanks.
 
The small box compressors like the one you have are not made to fill the large air bottles. They are made to fill the tanks and bottles that are on the airguns. Yours is rated for a max bottle size of only 0.5L (500 CC). It may work (no guaranty) if you fill for 10 minutes at a time with a 1/2 hr. cooling down period in between but, I don't think your compressor will last long if you fill large air tanks.
If you want to fill a large air tank, you should look into getting an air compressor that is rated to do so. You would also want to have a filter that would keep the water out of the bottle when filling. I agree with Skydivingmiami about getting the extended warranty for the compressor. My $700 compressor broke after two years of use. I only used it to top off the 480cc bottle on my rifle.
 
Does the compressor know what it is filling? A Bottle, a Cylinder? I have the same type of compressor as yours, I think that if you treat the compressor the same way all the time it won't matter. I fill My rifle about 4 times a day. The longest the compressor runs is about 4- 4.5 Mins. I then let it cool with the fan for the same amount of time. Now I am only filling a 2-300 cc tank, but the compressor doesn't know that. So If I did a bottle the same way, "Yes it would take many Fills" the same would work. And when your bottle balances out with the rifle, it will still have a lot of compressed air in it requiring less time to refill it. But that's just the way I look at it. If one is in a hurry, then the little compressor would probably fail. And yes, I did buy the Warranty! lol JMO
 
Does the compressor know what it is filling? A Bottle, a Cylinder? I have the same type of compressor as yours, I think that if you treat the compressor the same way all the time it won't matter. I fill My rifle about 4 times a day. The longest the compressor runs is about 4- 4.5 Mins. I then let it cool with the fan for the same amount of time. Now I am only filling a 2-300 cc tank, but the compressor doesn't know that. So If I did a bottle the same way, "Yes it would take many Fills" the same would work. And when your bottle balances out with the rifle, it will still have a lot of compressed air in it requiring less time to refill it. But that's just the way I look at it. If one is in a hurry, then the little compressor would probably fail. And yes, I did buy the Warranty! lol JMO
Unfortunately, the compressor does "know" because the pressure of the fill is very different. Say you fill your gun form 2000-3000 with the compressor. If you want to fill from a tank, then it needs to be above that pressure to get a fill. So if you fill your tank from 3000-3500 psi, the compressor sees an average fill pressure of 3250 vs. 2500 for filling the gun directly. That is a lot more load on the compressor for 100% of the time that it is running, and much more heat being generated too. It's not just about the time it spends running . . .
 
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Unfortunately, the compressor does "know" because the pressure of the fill is very different. Say you fill your gun form 2000-3000 with the compressor. If you want to fill from a tank, then it needs to be above that pressure to get a fill. So if you fill your tank from 3000-3500 psi, the compressor sees an average fill pressure of 3250 vs. 2500 for filling the gun directly. That is a lot more load on the compressor for 100% of the time that it is running, and much more heat being generated too. It's not just about the time it spends running . . .
So you are saying that the 3000 psi that I fill my Rifle with is different in a different Volume? If the Compressor is capable of filling the rifle/ tank to 3600 what is the difference? Volume is the difference. It will just take much longer.
 
Yes more volume than what that little portable compressor can handle I recommend a shoe box compressor to fill big tanks if you can find one used
So you are saying that the 3000 psi that I fill my Rifle with is different in a different Volume? If the Compressor is capable of filling the rifle/ tank to 3600 what is the difference? Volume is the difference. It will just take much longer.
 
So you are saying that the 3000 psi that I fill my Rifle with is different in a different Volume? If the Compressor is capable of filling the rifle/ tank to 3600 what is the difference? Volume is the difference. It will just take much longer.
The pressure is the main difference in terms of the impact on the compressor. It is more work for the compressor to fill to a higher pressure than a lower one, even if the volume is the same. I would assume the tank would be a larger volume, but the total amount of air used would be basically the same after the initial fill of the tank.
 
I own an inexpensive but functional and convenient $160 compressor from Amazon (https://a.co/d/8sHtOTR). I use it to fill my PCP rifles at my gun club. It’s LOUD even though it is a gun club and folks are shooting some loud rounds! I now see, however, what an advantage a carbon fiber fill tank would offer. I will study the issue so as to get other questions answered on my own but for now I would welcome responses to one question, please:

Can these modest compressors fill an Air Venturi tank without overheating or breaking due to the amount of air the tanks require? Or are professional sources - like “scuba shops” - really the only safe way to fill them? Thanks.

Get yourself a GX-CS4 and don't worry about the size of the tank being filled, and the bonus is that it will be very quiet while running.
 
I don't own any of the under 500W compressors but I agree with the sentiment that they are meant for filling guns. The CS4 may be an exception but due it's size my understanding is that a bottle fill takes hours.

I use my Yong Heng compressor, approaching 3 years old at the moment and going strong, to fill my 45 minute SCBA tank. Works fine. I added a small radiator and fans and can refill my bottle to 4000-300 bar while staying below 60 degrees C. I use NuVair oil in it which I think is important for it's longevity. I only fill my bottle about once a month, however. My Yong Heng pulls 3-5 times as much electricity as your compressor so a bottle fill takes 15-25 minutes. But it is noisy and takes up more space. I am using an inexpensive retired Scott firemans tank and a somewhat expensive fill set from Joe Brancato. Total cost about $600.

To me the big advantage of filling from a bottle is it's very fast and nearly totally silent.
 
I don't own any of the under 500W compressors but I agree with the sentiment that they are meant for filling guns. The CS4 may be an exception but due it's size my understanding is that a bottle fill takes hours.

I use my Yong Heng compressor, approaching 3 years old at the moment and going strong, to fill my 45 minute SCBA tank. Works fine. I added a small radiator and fans and can refill my bottle to 4000-300 bar while staying below 60 degrees C. I use NuVair oil in it which I think is important for it's longevity. I only fill my bottle about once a month, however. My Yong Heng pulls 3-5 times as much electricity as your compressor so a bottle fill takes 15-25 minutes. But it is noisy and takes up more space. I am using an inexpensive retired Scott firemans tank and a somewhat expensive fill set from Joe Brancato. Total cost about $600.

To me the big advantage of filling from a bottle is it's very fast and nearly totally silent.
Less than an hour for a 9L bottle from 240 to 310 bar with the CS4, and temps 113°/118° F (45°/48 C°) (coolant/head). Yes, it's slow, but low temps, no water, and quiet enough to watch TV or have a convo if it's in the same room. Plus, it's portable, no stinky compressor oil. No need to add any fans nor external water or cooling.
 
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Less than an hour for a 9L bottle from 240 to 310 bar with the CS4, and temps 113°/118° F (45°/48 C°) (coolant/head). Yes, it's slow, but low temps, no water, and quiet enough to watch TV or have a convo if it's in the same room. Plus, it's portable, no stinky compressor oil. No need to add any fans nor external water or cooling.
I’ll say it again … if the CS4 had been available at the time, I would likely have purchased it instead of my Alkin. I have no regrets on buying the Alkin, but I do wonder if I could have gotten away with spending 8 times less.
 
I’ll say it again … if the CS4 had been available at the time, I would likely have purchased it instead of my Alkin. I have no regrets on buying the Alkin, but I do wonder if I could have gotten away with spending 8 times less.
Don't second-guess the Alkin. You KNOW it's a solid compressor, and I, too, would have one today if I had the room and didn't need portability.

In a perfect world, we'd each own both, eh?
 
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I hear good stuff about the GX4, the thing is it still something made in China. I dont know long term where you can get parts.

I had a great deal on a Coltri this year, once you use a compressor that is made for filling tanks, you will never look back at the Chinese stuff.


It has been said before, air is expensive for our hobby.

Lets not forget we are dealing with 300 bar or more, that is not a joke if something fails.
 
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