First Steel Tank - Single LP85 or HP80

[rob.mwpropane]

No, they are 3442 psi standard 3/4” 200 bar valve with DIN inserts. And there’s no + rating so 3442 IS 100 cf, not some mythical 10% over to get the advertised CF.

I'm not around my PST tanks, but they're all 7/8" 3500psi... can't remember the model

 

[Eric Sedletzky]

I'm not around my PST tanks, but they're all 7/8" 3500psi... can't remember the model

I think mine is a PST?
Now you got me wondering, I need to go look.

 

[rob.mwpropane]

I think mine is a PST?
Now you got me wondering, I need to go look.

I would believe your memory over mine!!

 

[RIHappyDiver]

From what I can find, the PST E7-100 is as @Eric Sedletzky states. The PST 100, on the other hand, is as @rob.mwpropane states. So, could be that your discussing different tanks, same size by the same company. Is it a difference of age? Sounds like PST switched threads after a certain date, though not sure when.

Erik

 

[rob.mwpropane]

From what I can find, the PST E7-100 is as @Eric Sedletzky states. The PST 100, on the other hand, is as @rob.mwpropane states. So, could be that your discussing different tanks, same size by the same company. Is it a difference of age? Sounds like PST switched threads after a certain date, though not sure when.

Erik

Yeah.. I haven't had a chance to look. I'm sure my model is different though.

 

[Bob DBF]

Sounds like PST switched threads after a certain date, though not sure when.

The only thread difference over time was 1/2 to 3/4. 7/8 threads are for tanks 3500# service pressure or over.

 

[geoff w]

HP 80 and LP 85 are very different tanks. LP 85 is about 1.5" taller than a HP 100, so nearly the same gas volume at the same pressure, which makes a difference if you have trouble getting a good HP 3442 PSI fill. Also, HP 80 are especially sensitive to getting hot while filling, so if you want a true HP fill, you'll need to let it cool off, top up, then possibly repeat again (or fill to 4000 PSI and it will cool down to 3300). LP 85 dives similar to an old steel 72, just holds more gas.

For shore dives, it's hard to beat a HP80. It's like having a bowling ball on your back. You'll get knocked around less in big surf, and it's about 2 lbs more negative buoyant than a LP 85 or HP 100 (i.e., add 2 lbs of lead going from a HP80 to a LP 85). On a dive boat, if you're sitting on a bench, HP 80 is harder to gear up with, because you have to shimmy down to get your shoulders through the straps; a LP 85 will be easier to get in and out of while sitting down.

If you're diving salt water, definitely go for galvanized over painted finish, but you'll still need to wash well with fresh water after diving. Also, HP tanks seem to be a little more prone to internal rust than LP tanks

 

[Eric Sedletzky]

Also, HP tanks seem to be a little more prone to internal rust than LP tanks

It’s because they use a higher carbon steel for HP tanks.

 

[98TJ10]

Thank you everyone for the input, I appreciate it! I wound up finding a good deal and purchasing a galvanized Faber LP85. Thoughts on this tank for single tank dives in a 7mm and 3mm?

 

[RIHappyDiver]

I have two, and have used them as singles with 3, 5 and 7. Great tanks, enjoy it!

Erik