XS HP80 vs Faber HP80

[Rainer]

I cant find any number for LP72.

Here's a post that lists the numbers for the 2250psi LP72s: http://www.scubaboard.com/forums/ta...steel-lp72-2250psi-tank-spec.html#post5191610

Basically:

26 + (0) = 26lb, so about the exact same as a HP80.

Yes, finding one would mean turning to the used market. For cylinders, that's what I almost always choose to do (huge savings). I think I picked up our two 72s for just north of $50 each. Some really great deals on these cylinders (especially compared to >$300 for a new HP80).

 

[Hatul]

To archieve that, you need to compared weight of the tank + empty buoyancy number.

X7-80, 28 + (-3) = 25lb
HP-80, 32.5 + (-7.22) = 25.28lb
FX-80, 28.6 + (-1.74) = 26.86lb
X7-100, 33 + (-2.5) = 30.5lb
Cat S80, 31.6 + (+4) = 35.6lb

I cant find any number for LP72. Looks like X7-80 and faber HP-80 is about the same. FX-80 is 1 lb heavier. AL80 is almost 10lb heavier than X7-80.

Thanks. That is the right way to compare. However to get the empty weight of the XS HP80 I've seen different answers. I presume this is without the valve, right?

XS Scuba Worthington Steel Cylinder Specifications

the above lists 27.7 lbs

XS Scuba Worthington Steel Cylinder Specifications

this lists 13.1 kg which is 28.82 lbs

Scuba diving gear Tanks Steel Tanks at Scuba.com

this lists the same tank as 29.8 lbs

Adam

 

[halocline]

From the limited research I gather the LP72 steel tanks are not made anymore. Which would mean the used tank market, which is another problem.

Really its not. I've never bought a new tank, and I doubt I ever will. Buying used tanks, especially steel, is the way to go. You just need to look inside or have someone who has an idea of what they should look like do so. It's not rocket science, it's not even a real visual, you're just looking for corrosion. Tanks have zero moving parts (well, the valve, but so what...) and if kept in decent shape work every bit as well when they're decades old as they do when they're new.

Before you talk yourself into or out of anything, do a dive with a LP72 and one with a HP80. You won't have much trouble finding either to rent or borrow. I have a sneaky suspicion that's going to really change your perspective.

 

[Hatul]

OK I see an old LP72 with a yoke valve on Craigslist

voit steel scuba tank 72cf

for $60, but then I need a DIN valve. Are all the valves interchangeable?

http://orangecounty.craigslist.org/spo/2487705726.html

Here's another:
http://losangeles.craigslist.org/wst/spo/2540742207.html
"shorty" whatever that means

Any advice on these appreciated. As I said I use a DIN reg and don't want any questionable gear. How do I check for rust inside?

Adam

 

[JEC11718]

take off valve- shine light inside- see if rust is present. I found a 72 at a pawn shop, paid 50, got a hydro and valve rebuild, viz and sticker removal for 64...total spent 114. tank was originally manu...1972.

 

[Hatul]

take off valve- shine light inside- see if rust is present. I found a 72 at a pawn shop, paid 50, got a hydro and valve rebuild, viz and sticker removal for 64...total spent 114. tank was originally manu...1972.

I'm wondering if it's safe to overfill an old tank made in the 70's, and if dive shops will do it?

 

[halocline]

I'm wondering if it's safe to overfill an old tank made in the 70's, and if dive shops will do it?

Well the age doesn't have anything to do with it. Whether its "safe" to overfill any tank is a different topic that has certainly been bantered around. And there are degrees of overfill....filling a 2475PSI tank to, say 2700, is a very different affair than filling a 2600 PSI tank to 3500 as has been known to happen in the Fl cave country. I've found that some dive shops will go to 2250, some to 2475, some just assume all tanks are 3000.....IOW who knows what kind of chaos is going on. On the rare occasion that I need more gas and can't get a slight overfill, I transfill the last few hundred PSI from my HP100. I think that's happened once or twice in the several years I've owned the LP72s, usually with my LP72 doubles that I'm going to use for several dives w/out a fill.

To inspect it, you need some sort of light-on-a-stick. A strand of LED christmas lights works well, or any kind of inspection light that you can insert into the tank, then just look around. If you see big rust spots, deep pits, or anything that scares you, just walk away. A covering of light surface rust can be easily tumbled or whipped. If you're near any vintage divers in SoCal, (I think the freedom plate builder ZKY is there) I'm sure they'll help you.

The "shorty" tank you saw in craigslist is something different, it's either a LP or MP modern faber. I don't know anything about them, but if they're really short and really negative you might have some of the same trim issues that the HP80 is known for.

For the valve you'll have to find a DIN valve and replace the yoke valve. The tanks you posted about all appear to be using standard size valves. Alternatively you can put a DIN/yoke spin on adapter on your tank. Those work fine and they're handy to have if you only have DIN regs, but they do put the reg closer to your back.

 

[Eric Sedletzky]

Halocline, I'm up in Norcal north of San Francisco, not that it's a big deal I'm just clarifying.

I LOVE old school steel 72's. Best tank for quick shallow shore dives IMO.
I have 6 of them now, most were given to me and every one of them passes hydro every time and probably will continue to pass hydro for my kid my grand kids and my great grand kids.
To look inside just get a small mag light on a string and untwist the head completely off so the bulb is the only thing sticking out of the end (it will be on).
A haze of rust means nothing. Even small pits probably mean nothing. If there are big deep craters then walk away.

Anybody wanting to get rid of those old junk 72's that are useless and "bombs" waiting to go off please PM me and I will arrange for proper disposal.
Free pick up within a 50 mile radius!

BTW, I had a friend in a dive shop that used to routinely fill LP72's to 3000 all the time.
I'm not saying it's right but he used to do it and he didn't seem nervous about it.
I think they are around an 80 when filled to 3000.
I think hydro pressure is somewhere around 5200.

 

[halocline]

Hydro test pressure is 3750: 2250 X 5/3. At 3000 PSI they hold substantially more than an AL80, I think its about 86 cft. BTW, I use my freedom plate all the time; its an excellent piece of gear!

 

[Eric Sedletzky]

Hydro test pressure is 3750: 2250 X 5/3. At 3000 PSI they hold substantially more than an AL80, I think its about 86 cft. BTW, I use my freedom plate all the time; its an excellent piece of gear!

I stand corrected on the hydro pressure, thanks for clearing that up.
Also AL80's at 3000 aren't actually 80, they are more like 77.3 from info I gleaned.
That's a great idea with the trans fill whip to fatten up the 72's. I have an HP120 I could do that with.

I'm super glad you like the plate!