scuba tank

does anyone here have an info on scuba tanks? i have been thinking about putting a tank in my bed to use for air ratchets etc. i am an insurance appraiser and i can use it to take apart damaged vehicles to diagnose hidden damages. also, i heard that you must have the take stored right side up and when in use? is this true? any safety concerns with this and how does this hold up in the winter months ( i am living in alberta canada ).

 

Is there a reason that you want use a SCUBA tank specifically?

 

The Scuba industry is self-regulating, without a certification you're going to have a hard time getting the tank filled, though the paintball hobby has cut into this and some shops will fill if you sign a release that you aren't going to dive with it.
Helps to have some paintball related stickers on the tank.
There are no actual LAWS about a non-certified person getting a tank filled, but to hear dive shop employees talk, you'd think it was a felony.


Transport and storage:
Protect the valve. The tank does not have to be upright, just make sure that the valve is not in a position to be damaged by something in the vehicle, particularly during an accident.
Everyone hears stories about the "tank torpedo" that blasts through a block wall, and that can happen, but what usually happens is a tank left upright falls over, the valve cracks, and the tank spins.
You now have a 40 pound tank that breaks your ankles, you fall, and the tank proceeds to beat the shit out of you.

Use for air tools is not going to be very practical.
Even the largest double tank rigs used for deepwater technical diving only hold a combined total of about 280 cubic feet. You have a lot of pressure, but not a lot of volume.
Small hand tools generally require 5-10 scfm, so you're going to dump a single "120" in 10-20 minutes... and these are the big steel tanks.
The most common tanks are aluminum 80cf, so you'll dump one of them in 8-15 minutes.

Your main issues are going to be the tank overheating on a hot day. That's easy enough to mitigate... if it's a 3000psi tank, just don't fill it to more than 2700, but in practicality, it's not a major concern and I've never had a problem here in SoCal with in-car temperatures getting to 140 or so. I wouldn't do it in Arizona in August.

The other issue is moisture contamination causing corrosion of the tank.
Rule of thumb for divers is to avoid running the tank to below 500psi. Part of this rule is for safety... 500psi is not a lot of air when under water, but part of is is to ensure that there is ALWAYS a positive pressure inside the tank.
A lot of shops will require a visual inspection before refilling any tank that is brought in below whatever pressure the operator is comfortable with. I've seen some shops that'll refill a tank that's at 100 without question, and others that yank the valve for a visual at 499psi (which is BS).
Generally, moisture in the tank comes from a poorly maintained fill station. You can't just connect the tank to your garage compressor.
You need a quality compressor with multiple filtration and water separation stacks that is able to run to 3500psi.

Every 5 years, the DOT requires that the tank be hydrostatically tested.
This is the only LEGAL inspection requirement. See the first paragraph... the dive shop is not going to fill a tank that does not have a current, annual visual inspection sticker.
The visual inspection includes removing the valve and dropping a light into the tank to look for corrosion.

The visual inspection also includes an exterior inspection to note external rust or impact damage that could be a problem. Exterior corrosion is generally not a problem on modern aluminum tanks, and hot-dipped galvanized steel tanks are also pretty solid unless they've been stored in a warm environment with a damp surface in contact with the tank.

 

rich, as usual, nailed it. you would be better off with a portable gas-powered compressor if your running tools alot. in these unfortunate times, it shouldnt be hard to find a good used one as contractors constantly go out of business

 

If you're running C02 the bottle does have to be upright when in use or the regulator can freeze up.

 

Reading Rich's post, I just got an education. Thanks Rich.

 

1957, scuba "class" consisted of "Don't hold your breath, good luck!"

 

thanks for all the info everyone. especially rich!

 

Why not use a nitrogen tank for air tools that is what race teams use

 

Rich, how the hell do you know so much about stuff. I always enjoy reading your posts. lol

 

I carry my hp100's in the back almost all the time. I spend alot of time in Monterey diving. I was considering putting in a manifold that could connect to my tank a run certain accessories. Rich is correct about the requirements for the tanks. My intent is for less intensive accessories, ie. pressurized water tank for a rinse hose, tire fill, blow off nozzle. Like it was stated tanks can be laid down or stood up. Here is my tank rack, I have one on either side

 

Where did you get the rack from?

 

I used parts from trident dive.com, modified it to fit on my bed rail system

 

You need gas powered compressor. Air tools require a LOT of air, especially if you are running air impact and air ratchet. With just a tank you will be running out of air ALL the time...

 

Good information Rich. You reminded me of the days when I was living in Daytona Beach and helping out a friend of mine in his SCUBA shop! Good times there! I used to have a 80CF tank that I had clamped in my truck with a first-stage regulator built to connect an air line and regulate it to 90psi. We used it to air up tires and run short-term air tools for small repairs. Though it is obviously not a large amount of air, we found that it worked for our offroad trips to do minor repairs. If you are going to be doing a lot of disassembly, then I agree with others who suggest using a small, gas operated air compressor. Refilling of a SCUBA tank is not expensive, but if you are filling it up several times a month the cost will add up QUICK. Probably more than the fuel cost for a gas unit. SCUBA tanks are great for trail rides, but not for long-term use.

 

air impact would empty scuba tank in about 5 minutes.... CO2 is what you need,
or a dedicated compressor and storage tank.

 

Liquid CO2 is what you might be looking for...here's a writeup.
http://www.lieblweb.com/liquidco2.html

The CO2 is a liquid and expands as a gas inside the 'empty' portion of the tank (per say). You can't lay it on its side because the liquid would come out before the gas at the regulator.

I used a couple different sized tanks over the years. 5 and 20lb

 

If u are looking for a air tool option: look into getting a ARB compressor for about $170.00. Best option.

 

I have used a 1/2 inch impact with my scuba tank to do a full swap out of 4 tire/wheels combinations and still had plenty of air left in the tank. It is a viable alternative for a weekend wheeling trip, just not viable for his application of working air.

 

Been around the block a few times, both work experience and hobbies, and when I get into something, I jump in with both feet and learn everything I can.