Are Old Tanks Worth Hydroing?

-hh wrote

>> > What's wrong with getting it tumbled to remove the rust?
>>
>> Everytime you do it reduces the wall thickness and reduces strength?

> And a lot can depend on how the tank was stored. Upright can be Ok,
> but if it was stored laying down, then you can get a "rust line" on
> the bottom that takes a lot of tumbling to dig it all out, which
> results in significant wall thinning.

I was pretty specific about the conditions that would lead to scrapping the
tank. It included significant flaking and pitting, either of which are
likely to fail the tank on the next visual, with or without a hydro. Even if
the tank might make it one more time, the cost benefit of tumbling a steel
tank that old is limited and the risk of depending on such a tank for the
five years until the next hydro date is higher than I'd choose to take.

Lee

"Blah" <blah@hotmail.com> wrote in message
news:5ksfcsF56dv3U1@mid.individual.net...
> Greg Mossman wrote:
> > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
> >
> >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> >> valve off and shine a small flashlight into the tank. If you see scales
of
> >> rust, pits or any similar indications that the inside of the tank is
> >> damaged, drill a hole in the tank and start over. There's no point in
paying
> >> good money to test a tank you already know won't pass. If it's smooth
> >> inside, have it hydro tested.
> >
> > What's wrong with getting it tumbled to remove the rust?
> >
> Everytime you do it reduces the wall thickness and reduces strength?

Sure, you leave it run for a decade.

"Blah" <blah@hotmail.com> wrote in message
news:5ksfcsF56dv3U1@mid.individual.net...
> Greg Mossman wrote:
> > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
> >
> >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> >> valve off and shine a small flashlight into the tank. If you see scales
of
> >> rust, pits or any similar indications that the inside of the tank is
> >> damaged, drill a hole in the tank and start over. There's no point in
paying
> >> good money to test a tank you already know won't pass. If it's smooth
> >> inside, have it hydro tested.
> >
> > What's wrong with getting it tumbled to remove the rust?
> >
> Everytime you do it reduces the wall thickness and reduces strength?

Sure, you leave it run for a decade.

"Blah" <blah@hotmail.com> wrote in message
news:5ksfcsF56dv3U1@mid.individual.net...
> Greg Mossman wrote:
> > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
> >
> >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> >> valve off and shine a small flashlight into the tank. If you see scales
of
> >> rust, pits or any similar indications that the inside of the tank is
> >> damaged, drill a hole in the tank and start over. There's no point in
paying
> >> good money to test a tank you already know won't pass. If it's smooth
> >> inside, have it hydro tested.
> >
> > What's wrong with getting it tumbled to remove the rust?
> >
> Everytime you do it reduces the wall thickness and reduces strength?

Sure, you leave it run for a decade.

"Blah" <blah@hotmail.com> wrote in message
news:5ksfcsF56dv3U1@mid.individual.net...
> Greg Mossman wrote:
> > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
> >
> >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> >> valve off and shine a small flashlight into the tank. If you see scales
of
> >> rust, pits or any similar indications that the inside of the tank is
> >> damaged, drill a hole in the tank and start over. There's no point in
paying
> >> good money to test a tank you already know won't pass. If it's smooth
> >> inside, have it hydro tested.
> >
> > What's wrong with getting it tumbled to remove the rust?
> >
> Everytime you do it reduces the wall thickness and reduces strength?

Sure, you leave it run for a decade.

On Sep 13, 5:10 am, "Scott" <pugetsounddi...@gmail.com> wrote:
> "Blah" <b...@hotmail.com> wrote in message
>
> news:5ksfcsF56dv3U1@mid.individual.net...
>
> > Greg Mossman wrote:
> > > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
>
> > >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> > >> valve off and shine a small flashlight into the tank. If you see scales
> of
> > >> rust, pits or any similar indications that the inside of the tank is
> > >> damaged, drill a hole in the tank and start over. There's no point in
> paying
> > >> good money to test a tank you already know won't pass. If it's smooth
> > >> inside, have it hydro tested.
>
> > > What's wrong with getting it tumbled to remove the rust?
>
> > Everytime you do it reduces the wall thickness and reduces strength?
>
> Sure, you leave it run for a decade.

Thanks. That's what I was wondering. After all, if the tank is
tumbled to get rid of the rust, and it then passes hydro and a visual
inspection, what's the worry? I think my local shop charged me $15 or
$20 for a tumbling the last time, which wasn't much in the scheme of
things after the tank passed hydro and earned me another 5 years of
usage.

On Sep 13, 5:10 am, "Scott" <pugetsounddi...@gmail.com> wrote:
> "Blah" <b...@hotmail.com> wrote in message
>
> news:5ksfcsF56dv3U1@mid.individual.net...
>
> > Greg Mossman wrote:
> > > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
>
> > >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> > >> valve off and shine a small flashlight into the tank. If you see scales
> of
> > >> rust, pits or any similar indications that the inside of the tank is
> > >> damaged, drill a hole in the tank and start over. There's no point in
> paying
> > >> good money to test a tank you already know won't pass. If it's smooth
> > >> inside, have it hydro tested.
>
> > > What's wrong with getting it tumbled to remove the rust?
>
> > Everytime you do it reduces the wall thickness and reduces strength?
>
> Sure, you leave it run for a decade.

Thanks. That's what I was wondering. After all, if the tank is
tumbled to get rid of the rust, and it then passes hydro and a visual
inspection, what's the worry? I think my local shop charged me $15 or
$20 for a tumbling the last time, which wasn't much in the scheme of
things after the tank passed hydro and earned me another 5 years of
usage.

On Sep 13, 5:10 am, "Scott" <pugetsounddi...@gmail.com> wrote:
> "Blah" <b...@hotmail.com> wrote in message
>
> news:5ksfcsF56dv3U1@mid.individual.net...
>
> > Greg Mossman wrote:
> > > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
>
> > >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> > >> valve off and shine a small flashlight into the tank. If you see scales
> of
> > >> rust, pits or any similar indications that the inside of the tank is
> > >> damaged, drill a hole in the tank and start over. There's no point in
> paying
> > >> good money to test a tank you already know won't pass. If it's smooth
> > >> inside, have it hydro tested.
>
> > > What's wrong with getting it tumbled to remove the rust?
>
> > Everytime you do it reduces the wall thickness and reduces strength?
>
> Sure, you leave it run for a decade.

Thanks. That's what I was wondering. After all, if the tank is
tumbled to get rid of the rust, and it then passes hydro and a visual
inspection, what's the worry? I think my local shop charged me $15 or
$20 for a tumbling the last time, which wasn't much in the scheme of
things after the tank passed hydro and earned me another 5 years of
usage.

On Sep 13, 5:10 am, "Scott" <pugetsounddi...@gmail.com> wrote:
> "Blah" <b...@hotmail.com> wrote in message
>
> news:5ksfcsF56dv3U1@mid.individual.net...
>
> > Greg Mossman wrote:
> > > On Sep 12, 3:47 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:
>
> > >> - Steel tanks tend to last longer, but are vulnerable to rust. Take the
> > >> valve off and shine a small flashlight into the tank. If you see scales
> of
> > >> rust, pits or any similar indications that the inside of the tank is
> > >> damaged, drill a hole in the tank and start over. There's no point in
> paying
> > >> good money to test a tank you already know won't pass. If it's smooth
> > >> inside, have it hydro tested.
>
> > > What's wrong with getting it tumbled to remove the rust?
>
> > Everytime you do it reduces the wall thickness and reduces strength?
>
> Sure, you leave it run for a decade.

Thanks. That's what I was wondering. After all, if the tank is
tumbled to get rid of the rust, and it then passes hydro and a visual
inspection, what's the worry? I think my local shop charged me $15 or
$20 for a tumbling the last time, which wasn't much in the scheme of
things after the tank passed hydro and earned me another 5 years of
usage.

On Sep 13, 4:29 am, "Lee Bell" <pleeb...@bellsouth.net> wrote:

> I was pretty specific about the conditions that would lead to scrapping the
> tank. It included significant flaking and pitting, either of which are
> likely to fail the tank on the next visual, with or without a hydro. Even if
> the tank might make it one more time, the cost benefit of tumbling a steel
> tank that old is limited and the risk of depending on such a tank for the
> five years until the next hydro date is higher than I'd choose to take.

It's my understanding that only aluminum tanks fail catastrophically,
and even then it usually fails when filling and is therefore more a
worry for the dive shop than the diver. If the tank passes the rigors
of a hydro test, it's pretty much guaranteed to withstand another 5
years of mere air fills. Tumbling only costs $15-20, a fraction of
the cost of a new steel tank. Even at $20, that's only $4 per year.
If you tumble and the tank fails hydro, you're out a lousy $20 at most
(plus the cost of the hydro). Risking a potential loss of $20 versus
having the use of a steel tank for the next 5 years at a prorated
additional cost of only $4 a year is definitely a risk I'd be willing
to take. Obviously we all have different risk thresholds.