Tank and Fittings for Thomas FT Rifle?

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Mike informed me that the max fill on the Thomas rifle is 3300 psi, so It seems like a 4500 psi scba tank would be overkill and risk damage to the rifle. Is there some reason that's not the case?
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That's not the case. If your fill tank only fills to the same pressure as the rifle then you only get one full fill per tank full. The 4500 psi full tank pressure is controlled by using the shut off valve on the tank to close the tank when the pressure in the rifle reaches 3300 psi. A 4500 psi carbon fiber tank is desirable. That's a primary reason carbon fiber tanks are preferred over scuba tanks as a fill source for PCPs. Scuba tanks are typically rated to only 3300 psi so don't give enough full fills to justify their size and heavy carry weight.
 
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BUT, scuba tanks don't have a 15 year end of life date. A scuba tank can live potentially forever, or at least until it fails a hydro. On scuba diving forums I've found instances of guys still using scuba tanks that were made in the seventies, and divers are much rougher on their tanks than us airgunners. 

So, if you're set-up with a bunch of high fill pressure guns and/or high power guns, than yes, scba carbon fiber will give you lots of fills, but you'll need to buy another $500 one in 15 years, at most. 

BUT, if you've got low pressure guns, and/or you own a compressor to be able to keep your tanks near 3000 or 3300 all the time, scuba tanks will/should last a long time (decades).

I'm a relatively young guy and hope to shoot for a long time, so I bought new SCUBA tanks. 

I have four PCPs, the highest fill pressure of them being the Veteran. I usually only fill it to whatever is in my tanks but occasionally I'll use the hand pump to get it up to 230 or so bar. The Veteran, at 20fpe, gets lots of shots before I'm off the reg, and it's quiet without adding extra length with an additional moderator. My primary field target gun is a Mac 1 Hunter. It gets 45 very consistent shots from 1550 to 1300psi. I get an incredible number of fills out of an 80cf, 3000 psi scuba tank with that gun. 

I see new guns taking a 300 bar fill and that just seems crazy to me. That much pressure is harder on orings, fittings, sealing faces of valves, etc. And I would suppose it'd be alot harder on the human body if a tank, fill whip, or air chamber on a gun lets go if you're anywhere near it when it happens.

I realize that I'm in the minority with my heavy scba tanks but they work for what I like in PCPs, 20fpe or less. And mostly lower pressures. 

Just an alternate viewpoint to the tank aspect of our hobby.
 
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BUT, scuba tanks don't have a 15 year end of life date. A scuba tank can live potentially forever, or at least until it fails a hydro. On scuba diving forums I've found instances of guys still using scuba tanks that were made in the seventies, and divers are much rougher on their tanks than us airgunners. 

So, if you're set-up with a bunch of high fill pressure guns and/or high power guns, than yes, scba carbon fiber will give you lots of fills, but you'll need to buy another $500 one in 15 years, at most. 

BUT, if you've got low pressure guns, and/or you own a compressor to be able to keep your tanks near 3000 or 3300 all the time, scuba tanks will/should last a long time (decades).

I'm a relatively young guy and hope to shoot for a long time, so I bought new SCUBA tanks. 

I have four PCPs, the highest fill pressure of them being the Veteran. I usually only fill it to whatever is in my tanks but occasionally I'll use the hand pump to get it up to 230 or so bar. The Veteran, at 20fpe, gets lots of shots before I'm off the reg, and it's quiet without adding extra length with an additional moderator. My primary field target gun is a Mac 1 Hunter. It gets 45 very consistent shots from 1550 to 1300psi. I get an incredible number of fills out of an 80cf, 3000 psi scuba tank with that gun. 

I see new guns taking a 300 bar fill and that just seems crazy to me. That much pressure is harder on orings, fittings, sealing faces of valves, etc. And I would suppose it'd be alot harder on the human body if a tank, fill whip, or air chamber on a gun lets go if you're anywhere near it when it happens.

I realize that I'm in the minority with my heavy scba tanks but they work for what I like in PCPs, 20fpe or less. And mostly lower pressures. 

Just an alternate viewpoint to the tank aspect of our hobby.
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The two biggest drawbacks of scuba tanks are much lower air capacity and the "clunk factor" of larger size and carry weight. My first tank was a 100cf aluminum scuba tank with a 3000 psi rating. That was 17 years ago when affordable high pressure compressors were unheard of. I paid $175 for an aluminum tank which was almost new. It weighed 40 pounds and was double the length and triple the weight of a 9 liter SCBA carbon fiber tank. It was a PITA lugging that big tank around yet only getting a dozen full fills before needing a refill at a dive shop. I didn't like the condescending attitude at several dive shops in town that refused to fill tanks without a diver certification. PCP tank owners were treated like seond class customers and were never encouraged to return.

Fast forward to today where 4500 psi compressors are within the budget of many PCP owners and 4500 psi carbon fiber tanks are commonplace. If you own a compressor and maintain your carbon fiber tank the 15 year expiration date is not a concern. The DOT currently sanctions a 15 year life span for carbon fiber tanks for the protection of firemen wearing SCBA tanks. Firemen wearing SCBA tanks cycle them from 4500 psi to near empty. This means frequent duty cycles which expand and contract tanks more than a PCP user ever does when filling a tank that gets refilled from 2-3000 psi. A PCP owner doesn't subject a carbon fiber tank to the wear and tear as a fireman does in firefighting. Any PCP user with a good compressor and moisture filter setup can use a tank well beyond 15 years. The convenience and capacity of carbon fiber tanks far outweighs their new cost. That's why scuba tanks aren't sold by airgun dealers. Their only advantage is lower price and hydro sanctioned life beyond 15 years. Their liability is size, weight, and low pressure holding capacity.

I understand and appreciate that a scuba tank is usable for some individuals in special circumstances. If an owner keeps a tank in a stationary location, or enjoys the exercise of carrying a heavy tank,or only uses low fill pressure PCPs, or has budget constraints then a lower cost steel tank is an option. The best fill tank type for the great majority of PCP owners is a 4500 psi carbon fiber tank. It isn't the cheapest, but it is the best value if all factors are considered. Carbon fiber tank users outnumber scuba tank owners and hand pump owners by an overwhelming margin. A scuba tank is best for a diver, and a carbon fiber tank is best for a PCP owner.


 
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So with the 300 BAR carbon fiber tank, I presume it has a manometer that displays the pressure in the tank. The Thomas rifle does not have a manometer. How do you know when to shut off the valve when charging it?
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Some have two gauges that show the pressure remaining in the tank and the pressure that is going into the rifle. When you open the tank valve, the important gauge is the one that is monitoring the pressure coming out of the tank. Your Thomas rifle doesn't need a manometer. When youi open your tank valve and the pressure in the output gauge shows the fill pressure you want to reach in your Thomas, then you close the valve. Older PCPs from early 2000s back did not have manometers on the rifle. You filled them by monitoring the pressure gauge on your tank. The secondary gauge that reads the pressure in the tank isn't a necessity either. You can put a dead head plug on the end of your fill hose then open the tank valve. The same gauge that shows the fill pressure in your rifle shows the remaining pressure in the tank with a deadhead attached after it stops.
 
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Please forgive the seeming pedantry, but I'm having no luck finding a SCBA tank with two manometers. Are you supposed to combine one of these

https://www.amazon.com/IORMAN-Universal-Paintball-Composite-Cylinder/dp/B075GDCV76/ref=sr_1_1?keywords=scba+%22carbon+fiber%22&qid=1552014215&s=gateway&sr=8-1

with one of these?

https://www.amazon.com/Paintball-Station-4500psi-Filling-Charging/dp/B0713RV7MJ/ref=pd_bxgy_200_img_2/141-0254404-3427939?_encoding=UTF8&pd_rd_i=B0713RV7MJ&pd_rd_r=c6f6377b-414e-11e9-b0e4-e9578ee0e289&pd_rd_w=NPQ6G&pd_rd_wg=zmih4&pf_rd_p=6725dbd6-9917-451d-beba-16af7874e407&pf_rd_r=EZ36379R6XS59BJ6S679&psc=1&refRID=EZ36379R6XS59BJ6S679

And what is this "recommended" doohickey for?

https://www.amazon.com/Paintball-Airsoft-Disconnect-Adaptor-Stainless/dp/B01N7XX0W2/ref=pd_bxgy_200_img_2/141-0254404-3427939?_encoding=UTF8&pd_rd_i=B01N7XX0W2&pd_rd_r=55821181-414f-11e9-b3da-9de4a55f7ce9&pd_rd_w=zxjNt&pd_rd_wg=A47RR&pf_rd_p=6725dbd6-9917-451d-beba-16af7874e407&pf_rd_r=PKS5582X57WSWCBWE1D6&psc=1&refRID=PKS5582X57WSWCBWE1D6
 
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Let me clarify. You're correct that there is no tank with 2 gauges. Most tank valves have no gauge for reading pressure in the tank. Some of the one's coming out of China now include a gauge as does the one shown in the photo. Most Chinese tank gauges read in Mpa which is basically Bar x 10. So 30 Mpa is 300 Bar which is 4500 psi. Remember that if you buy a tank from China you need your own compressor to fill it as most Chinese tanks aren't DOT certified. Without DOT certification, no commercial tank filler will fill your tank nor will any hydro test facility certify it. Chinese tanks with DOT certification exist, but they cost as much as buying a tank in the U.S. Also, if you use Aliexpress instead of Amazon, the same equipment sells for much less. However, it will be shipped from China in most cases which will add a week or two to the shipping time.

Yes, the fill station in your second link contains the gauge that only shows pressure after you open the tank valve. That is the gauge that you would read to see what the pressure is in your air rifle. You shut the valve when the pressure on the fill gauge reaches the amount you want in your rifle.

The third item you show in your post is a male to male foster adapter. It is used when connecting two hoses that both terminate in Foster female quick disconnects. It is used mostly when someone has a compressor that terminates in a female foster quick disconnect and they are filling a tank that has a hose that also terminates in a female foster quick disconnect. That $9.95 adapter on Amazon can be found on Aliexpress for $1.50.
 
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Pewpew, I fill mine to 200 Bar with foster fill. I would recommend a 4500 psi SCBA bottle.

I get over 100 shots per fill, but I have the long barrel 23.75" with longer air tube.
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How many PSI or BAR can the Thomas cylinder take? I’m told it does not have a manometer, so how do you avoid overfilling it?
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Sorry it took me so long to get back to you. Yes, the Thomas cylinder can take 3300 psi as Mike has stated, and probably more but I wouldn't chance it. I'd stick with 3000 psi or 200 Bar which is 2900 psi.

I just use the gauges on my fill assy on my SCBA tank when filling my Thomas. Mine only have the one gauge but I use a quick disconnect test plug to check the pressure inside of my tank.

" Air Venturi quick disconnect test plug

a handy way to plug the female quick-disconnect on your tanks fill hose to check the pressure inside of tanks that do not have an internal pressure gauge by blocking the airflow to allow the use of an in-line gauge. 

the test plug in the standard quick disconnect coupling at the end of the pump hose to test your pump. The plug blocks airflow, providing a contained circuit to test. "

https://www.pyramydair.com/s/a/Air_Venturi_G6_G7_Quick_disconnect_Test_Plug/6682



Joe Brancato has a really good video explaining different tanks and fill systems.



https://youtu.be/ypyq-1MaSlc



Hope this helps bud.

Jimmy
 
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