Aluminum or Steel?......

[TechBlue]

I am a diehard.....

Wet 8mm, cold, murky water lobstering and scallopping in MA.....

Thanks for the advice......

You are a nut job what are you using for a BC? If you say horse collar you're on your own

 

[DiverDMD]

You are a nut job what are you using for a BC? If you say horse collar you're on your own

Now when you say BC.......are you referring to Boston College?.........

I had steel tanks in my younger days when I was diving in Italy, then moved to Cali.
and switched to Alum. in my college days so......

Here in MA I am going back to my "origins" and will buy steel......

Should I just get 2 100s? (Obviously not attached)

 

[reservecops]

If someone doesn't mind, what's the different/benefit of HPs over LPs (steel) if you can't find anybody to fill an HP to full capacity?

Further, are HPs predominately designed for DIN connections?

I have been diving for a little over 3 years and have all my own gear, save tanks and weights. Trips are generally to warm waters, so I (obviously) don't travel with tanks. However, I live in MI had own a 30' boat on Lake St. Clair (between Lake Huron & Lake Erie, about a mile from the southernmost mouth of the St. Clair River), and have been thinking about expanding my diving horizons to colder water.

 

[elan]

Now when you say BC.......are you referring to Boston College?.........

My bet he was referring to Boston Cream donuts sold at Dunkin

 

[PullmanSCUBA]

Just to put in my two cents I own both Steal and Al. When given the choice to dive one or the other I always pick the steal. I usually only dive the Al when I am trying to make two dives without going back to the dive shop.

 

[H2O 70]

HP vs. LP

HP tanks have a fill rating of 3442psi. LP tanks have a fill rating of 2400psi.

You can always get a full fill on LP tanks. You may not be able to get a full fill on HP tanks.

I have yet to find a shop that can't get me a full fill on HP tanks.

A HP 130 is almost the exact same physical size as an LP 95.

You can get HP tanks with a 300BAR DIN or a 200BAR DIN valve. The 200BAR DIN is likely a pro valve and will also accept a yoke reg. The difference between the 300 and 200 is two less threads. HP tanks are not necessarily only for DIN connections. Although IMO DIN connections are the way to go, but that is a separate argument.

For DanDMD what is your SAC rate and how deep and long do you typically dive? I've got HP100's and HP130's. I like them for different reasons.

I like my HP 130's for diving off of NC where your wrecks are 100-120fsw. I can end up with 10 minutes of deco and still get back on the boat with 1000-1100psi left.

I like my HP 100's for the shallower reef type dives, checkout dives, pool work and aquarium work.

 

[elan]

Fo me I found the sweet spot of the LP tanks is around 85 cuf bigger are heavier and HP starts to make sense. Lover HP like HP80 is not worth the hassle dealing with high pressure.

I also found that filling to the LP rating is easier even if the shop has the HP system. May be it's here only.

@H2O 70 I think LP95 is the same as HP119, HP130 is of the same size as LP104

 

[halocline]

If someone doesn't mind, what's the different/benefit of HPs over LPs (steel) if you can't find anybody to fill an HP to full capacity?

Further, are HPs predominately designed for DIN connections?

I have been diving for a little over 3 years and have all my own gear, save tanks and weights. Trips are generally to warm waters, so I (obviously) don't travel with tanks. However, I live in MI had own a 30' boat on Lake St. Clair (between Lake Huron & Lake Erie, about a mile from the southernmost mouth of the St. Clair River), and have been thinking about expanding my diving horizons to colder water.

HP tanks are relatively recent arrivals in the scuba world (compared to 3AA LP tanks) and I suspect will eventually dominate steel tank use in scuba. Most of the HP tanks are "special permit" tanks, meaning the DOT regulations governing their testing are different. If you compare some popular LP and HP tanks, you find that the physical sizes are very similar, with differences in capacity based on their pressure ratings. For many years cave divers used LP tanks, but overfilled them to roughly where the newer HP tanks are rated, in order to get the extra gas. Overfills are probably getting more difficult to come by, and since the HP tanks can be legally filled to the higher capacity, there are not many real benefits to LP tanks, other than they can often be found at a better price. They also practically never fail hydro, due to the lower test pressure, and since there is no DOT exemption on them, the permit for their use will never run out. The HP tanks have been known to occasionally fail hydro, especially some PST tanks. There was also an issue regarding the expiration of the DOT permit of PST HP tanks, but I believe I heard somewhere that another company renewed the permit, or that's it's surprisingly inexpensive to do so.

For the typical 3442/3500 PSI rating, most modern regulator yokes are fine, but DIN connectors are less likely to blow an o-ring. Many of the HP tanks, like fabers FX100s, come with convertible valves so you can use either DIN or yoke regs on them.

 

[H2O 70]

@H2O 70 I think LP95 is the same as HP119, HP130 is of the same size as LP104

I think you're right.

 

[njedrn]

Thanks for all the info guys...