Doubles Tanks Must Have Same Height???

[Pook-60]

Howdy

I'm a little confused. When I discussed tank purchases with my LDS the tech said the tanks have to be exactly the same height. Reason: To mitigate damage to the manifold. Following that logic...he said the LDS would need to request special matching of tank heights at the factory to ensure the tank heights were exactly the same (or within XXX thousandths).

My single-cylinder brain can't quite get past two different options when assembling a doubles setup:

1. The tank bands can be used to correct significant mismatches in tank height (I'm talking something less than a half-inch). I believe (as in I don't really know) that the bands would secure the tanks to each other suffecient to prevent shifting

2. Cylinder boots can be shimmed to make up for height differences

Thots?
Dane

 

[markfm]

Do they also have to be assembled with a lefthand wrench?
(I don't dive doubles, but never heard of the special-factory-order line before -- something smells fishy. Same basic size/height is one thing, but special factory order?)

 

[JeffG]

Howdy

I'm a little confused. When I discussed tank purchases with my LDS the tech said the tanks have to be exactly the same height. Reason: To mitigate damage to the manifold. Following that logic...he said the LDS would need to request special matching of tank heights at the factory to ensure the tank heights were exactly the same (or within XXX thousandths).

You are dealing with a typical shop monkey. He's an idiot, find another store.

 

[amascuba]

ditto to what Jeff said.

Is it required to have the exact same size tanks? No It's going to hold gas either way. At that same time though I refer to a common saying "If somethings worth doing, then it's worth doing right or not at all".

Do you have to request same tanks heights from the factory? No. Tanks are molded from molten metals. Just buy two tanks the same vendor and model. Such as Luxfer S80.

 

[Ben_ca]

LimeyX had problems finding X7's that matched up... He had a thread about it a while back... Seems that the tanks coming from the factory are inconsistant with regard to ht. I didn't have a problem with my PST E7-100's.

 

[Don Burke]

Welcome to the world of "close enough."

 

[Meng_Tze]

Technically the tanks dont have to be the same height. As long as you have roughly the same diameter for the bands, one tank can be 10" shorter than the other.

BUT
I have not seen mismatched tanks in doubles set up, they would not stand well on their own and gas calculations becomes a bit more difficult. So in real life, yes all tanks are the same model as said below. 2*Al80's, 2*LP108 etc.


There is no 'special order' from factories as far as I know on standard tanks to match tanks up. Special orders usually are for tanks that are out of stock, older models etc.

All my four sets of doubles have been put together with standard order tanks from a standard run at the factory. So tell you LTM (local tank monkey) to shut up and order 2 of the same tanks.

 

[The Kraken]

The "tech" at your LDS is an interesting person.

the K

 

[jonnythan]

Let me guess.... the shop will charge extra for ordering special matching tanks.

I've seen the "same" tanks that have a difference of almost an inch. I wouldn't want to make doubles out of those because they would lean to the side when assembled. However, as long as they're reasonably close they're fine.

 

[Pook-60]

Yup...OK...got the picture.

Thanks guys...didn't make sense to me either. That'll make my doubles buy just...a little easier

TX
Dane