PST LP 104 question

[large_diver]

Question.....

My LDS has referred me to someone who is offering to sell me a "lightly used" LP 104. The shop estimates he has used the tank for only about 5 dives (they want me to buy it so that the seller can buy an HP from them with the proceeds....).

I got a look at the tank this weekend.....when he gave it to me, I mentioned that it looks like it's been used for more than 5 dives.....he confirmed the 5 dive estimate. THe LDS did a vis inspection April 2002 (current sticker on the tank).

When I got it home, I knocked the boot off to have a look at the bottom (UK boot). The portion of the tank under the boot is discolored......kind of a white-ish glaze on the tank in the pattern of the boot. I tried scrubbing the glaze off with water and a dish brush -- a little of it came off, but it largely stayed the same.

Is this something to be concerned about? My worry is that the guy never rinsed this tank, never took the boot off, and didn't store it in a sheltered, dry location.

The price is fair, and he is including an OMS valve he added on later (the type you can convert from DIN to yoke).

Comments? Thanks.

-Chris

 

[Goldminer]

Originally posted by large_diver
Question.....

When I got it home, I knocked the boot off to have a look at the bottom (UK boot). The portion of the tank under the boot is discolored......kind of a white-ish glaze on the tank in the pattern of the boot. I tried scrubbing the glaze off with water and a dish brush -- a little of it came off, but it largely stayed the same.

Is this something to be concerned about? My worry is that the guy never rinsed this tank, never took the boot off, and didn't store it in a sheltered, dry location.

Comments? Thanks.

-Chris

I just purchased a pair of PST LP95's 1 week ago and have now dove one of them (fresh water). It has developed a bit of milky white haze in patches (particularly under the tank straps) after only 1 dive. So I got out the pamphlet the tanks came with and read it. According to the pamphlet this is normal. The hot dip galvanized coating is apparently sacrificial and designed to go hazy. The manual said not to scrub it off. Only rinse it with fresh water or wash with a mild detergent. I guess this haze protects the tank some how and removing it accelerates the oxidation of the zinc.

Your concern about salt water under the boot is a valid one. The manual warns about the need for rinsing this area after each salt water dive. I am no expert but, based on my experience of the last week, if the white glaze you describe is not severe I suspect it is normal hazing and not necessarily indicative of a lot of use. I got a bit of it after only 1 dive in fresh water so mine can't be salt induced. My recollection of university chemistry would indicate that the phenomenon would occur faster in salt water.

 

[Uncle Pug]

...since I never rinse it... nor scrub it... nor polish it... it looks like a plain old galvanized anchor. ;-)

Hey Chris... you don't want that tank... you need to get one of those pretty painted fabers and send that nasty old galvanized 104 to Uncle Pug.

Knock the boot off before you send it. You can nail it to the garage wall to hang hoses and stuff on.

 

[metridium]

Originally posted by Uncle Pug
Hey Chris... you don't want that tank... you need to get one of those pretty painted fabers and send that nasty old galvanized 104 to Uncle Pug.

First L_D's MC Storage Pack, and now his 104.....

hmmmm.....

You wouldn't be casting a covetous eye on thy neighbor's gear, now would ya, UP?

 

[rcohn]

The galvanized coating (zinc) on the tanks is a sacrificial anode. It's meant to corrode to protect the steel underneath. It happens very quickly and the discoloration is completely normal.

Ralph

 

[large_diver]

Thanks all -- this is the answer I was hoping for.

UP -- I'm keeping the 104, but if you want my Faber.....;-)

-C

 

[Uncle Pug]

Originally posted by metridium
You wouldn't be casting a covetous eye on thy neighbor's gear, now would ya, UP?

I need to be very careful about that.... and not just for the reason you might suspect....

Last week while picking up a friend for a dive I noticed a large, beautiful tree in front of the house with a particularly nice straight trunk and thought about my exercise program for DIR divers and how that would be a nice tree too....

I had to abruptly jerk myself back from coveting.... and to be thinking of falling such a beautiful tree seemed even worse than coveting...

But still I imagined that within the trunk of that tree there lived guitar tops that would sing if only liberated...

And again I had to avert my gaze in shame...

The next day my friend (unaware of my coveteous thoughts of the tree) emailed asking if I wanted any firewood... the tree had let a huge limb drop onto the roof that very night and the whole tree needed to come down.

Shane is over there right now loading up the rest of the firewood... I will deal with my section of the trunk later.

And yes, I apologized...

And no, I don't want Chris' pack or tank... that is my way of saying that he should keep it and use it.

Psalm 37:4 ~ just be careful what you desire.

 

[metridium]

Originally posted by Uncle Pug
And no, I don't want Chris' pack or tank... that is my way of saying that he should keep it and use it.

That was never in doubt, UP. I just couldn't pass up an opportunity to tweak your beard, so to speak.

 

[Uncle Pug]

Originally posted by metridium
I just couldn't pass up an opportunity to tweak your beard

...I couldn't resists the opportunity to post an anecdote.,,