Don't Tumble Your Tank - Scuba Tech Tips: S13E08 

Thats a good saying. Have your LDS put that on a t-shirt, make a lot of sense. Safe diving Scott. A.

Hello and first of many years ago steel tanks were the only tanks for divers. They did sell a plastic bag that went inside the steel 72 cu/ft tank to "protect it". BUT when the valve was threaded in it cut the plastic so moisture was inside anyway. Good marketing but bad product. It was by AMF called the "Lifeliner" Watch Vintage Scuba S07E17 on 72 cu/ft tanks. The rubber plug is what its called. Your correct about the aluminum oxide on threads is bad but its actual a threaded plug thru all threads. Just what i call it. Much appreciate your feedback and thanks for watching. A.

Oh and thanks for the feedback too. A.

Speaking of steel 72’s I still dive mine which is 52 years old. Am I right that without a 10% overfill you could get with a plus mark, a 72 is really just a 66 cubic foot tank at 2250 psi?

@@AlecPeirceScuba_SeaHunter ahh I see you actually use a threaded plug thing that really protects the threads.You know what you are doing its concerning that others might just try this with no clue.. I have seen what 300bar does when it gets out in a hurry...

A visual inspection will determine if a tank needs tumbling to clear it out. It should be a rare event to tank tumble. Any more that once in 10+ years and there may be another problem with the air quality, tank valve, or emptying the tank to zero pressure. A.

That is a great story Jacques. Thanks for sharing and glad you took a change on that tank. A.

That is awesome! Good to have you back in the water and moving up. Glad my ramblings help you in some way. Dive safe my friend. A.

Back in high school. Oh my you must be so old by now! HA. I have not changed at all, right? Thanks for watching and hope you learned something in high school too. A.

I suggest before spending time and money, get the tank a Visual Inspection first to see if corrosion in/out makes the tank unsafe to fill. If it passes VIS, get a hydro test and if it passes, your dive shop can tumble clean the inside. As for the outside, it's not recommended to sand/polish which thins the outside. Get a cool tank wrap to cover the ugly outside. Hope this helps. A

Certified scuba air fill has virtually zero moisture so a filled tank will be clean until its next visual or hydro date. The majority of dirty tanks comes from: bad air quality and emptying the tank with the valve open. Divers spend lots of $$ to buy shinny new gear but rarely take excellent care of it. Thanks for the question Tim. A.

They have to take the tank valve off for the hydro so why not do a Visual Inspection before? A few LDS prefer to do it after hydro to verify the tank is totally dry before filling it. A.

Did not know that Richard. I'm smarter now than yesterday! A.

Show the shop this video and ask for a better price. Maybe they will agree if you're a returning customer. A

​@@AlecPeirceScuba_SeaHunter The shop owner has already told me "I don't make any money off VIPs ($30 VIP+fill), fills ($10) or tumbling ($55)." Given I recently took the visual Inspection course, and know the process, there's no way VIPs aren't profitable at that price. I took the class because maintaining a small fleet of tanks was getting FAR too expensive. Based on my interactions with the LDS owner, I suspect he'd treat it as an insult if I tried to negotiate prices with him.

The regulations for scuba tanks in Canada and the USA are almost the same. A Canada LDS hydro is valid in the USA. Any USA LDS will fill a tank after checking your: C card, last visual date and hydro date stamp. Nothing else really matters except the VISA card! Thanks and enjoy the warm FL weather Will. A.

That is strange as its not what the regs are made of, titanium or brass, but the o-rings must be O2 compatible also. Simple check is to go online, find the reg maker, read their owners manual. I don't know of any reg, regardless of metal, that is not O2 compatible brand new. Nitrox is the most popular diving speciality next to photography. Check again then take your business to a LDS that tells the truth. A.

Does not really matter. Long term storage and repeated filling affect tanks but neither is dangerous if tested for VIS and hydro regularly. Take any large Caribbean dive resort that fills a hundred tanks a day x 7 days x 365 days + salt and sun/heat is a lot of filling cycles on an aluminum 3,000 psi tank. Yet no reported explosions or issue due to testing and the quality of todays tanks. A

My pleasure Brad. Let's see if I can help you get to Instructor some day. A

That was my point and glad you grasped it too. A.

Hi Rick. Totally agree but too many home car mechanics think scuba is just the same. If your car stops, another car will come by, if your reg stops, oh crap!! A.

If the tanks look like they would pass hydro and a VIS, offer them for sale first. Lots of vintage divers collect useable tanks. If no offers, they make great wind chimes. A.

Shouldn't need another tumble every again if taken good care of them. It's really a rarely needed process but an important one. A.

Generally all steel tanks after hydro tested, are coated with a flash drying protective coating, specifically to prevent rust. They are then put valve down on a drying stand blowing room temperature air (warmer is OK if the tanks have been coated). This ensures a dry tank until the next annual visual. Hope it helps and hello from way north in Canada. A

Tumbling is a cleaning process and not affected by the 5 year hydro testing mandate. A

I think so. A

Visual Inspections are somewhat subjective. That is, you cannot weigh the tank & say Yes or No. It requires looking at the tank and making a decision. Different inspectors will make different decisions. Some are adamant that the tank have an "as new" appearance. Others recognize that the tank is not new & there are bound to be some imperfections from use. Rust is only an issue if it is likely to flake off or fall off the surface. In that event it could potentially enter the air flow to the regulator & block the filter. In my opinion, after almost 50 years of scuba service, a very thin coating of 'surface rust' is unlikely to be a problem. That rust will not fall off, certainly not in a volume such that it could travel to the top of the tank, circumvent the dip tube of the valve (which is there for that very reason), travel through the valve & enter the regulator. I have seen regulator filters that are red from rust but that is almost certainly the result of poor/no maintenance. It takes a long time & a lot of rust to cause that. Surface rust is easily measured by simply scratching it with a stainless steel probe - part of a visual inspection. If the rust is solid on the wall, it may pass. If you are concerned, note that surface rust can be removed easily, usually by tumbling or using a hone. However, when the tank is rinsed after the cleaning, surface rust will almost definitely reappear. It may seem to be a no-win situation but, using a rust preventative in the rinse water & drying quickly ought to result in that elusive 'as new' appearance. Hope that answers your question. Alec

Glad you enjoyed it Seven. A.

It follows gravity always. Even under pressure a drop of water is heavier than the compressed air. That is why tank valves have 'dip tubes' to prevent water/junk going through the tank valve into your regulator. A

@@AlecPeirceScuba_SeaHunter Thanks a bunch Alec

There are several commercial products plus home mixed solutions to inhibit corrosion in steel tanks. Read this link for recommended product names: scubaboard.com/community/threads/supplies-for-o2-cleaning-a-steel-tank.218269/ A

Why not watch some more to be sure? Can't change my way of presenting at 75 so pick another channel please. A

@@AlecPeirceScuba_SeaHunter Because some of your videos are actually worth watching. It's just a slog getting through the crap to get to them.

@@AlecPeirceScuba_SeaHunter I actually love the conversational manner of the videos, it is one of the reasons I follow this channel and not some of the other ones. Please don't change them!

​@@AlecPeirceScuba_SeaHunter one of the best answers.. :)

Always welcome William. A.

Hope you like. A.

@@AlecPeirceScuba_SeaHunter hahaha class as always. Thank you for making the content you do and for the gift of it being ad free!

Thanks athukora. A.

Hello Hu. I already did a review of the SMACO mini dive system. See my video ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-B0YygWckvX4.html. Not interested in anymore on this system. A.

You could try a not chilli to burn the insides clean! HA. A