Steel/Aluminium Transition Joint & repairs/patches to the superstructure

[Isabelle Prondzynski]

Isabelle, what the article didn,t mention is that John Browns did NOT have more than 2 people capable of welding aluminum!!!!! They had to set up welding school when they got the contract!

Fascinating, Rod! Any additional information / stories, etc. welcome.

Presumably QE2 always needed to carry someone skilled in welding, to carry out the regularly necessary repairs whenever they arose...

[andy liney]

Wasn't one of the big problems the interface between the aluminium superstructure and the steel, where aluminium and steel couldn't be allowed to be in conductive contact for electrolytic corrosion reasons (thus requiring the rather ugly resinous joint that used to be evident)?

[Rod]

Nobody on the ship was able to weld aluminium. Nor did we have the equipment. Several people, myself included were able to weld steel, copper brass etc. But we were not certified. Any boiler work for example we had to hire outside welders.

[pete cain]

Rod, have belatedly looked at this topic, & wish to (very nicely) contradict you, we were onboard QE2 in 2007, on 1deck, stbd side to the right of the Pavillion was a room , showers & changing;  my memory fails me here, but, there might 've been another small room aft of  it, used for storing towels & misc bits, there might not , I really am uncertain, however the crew had cut a piece of ally bulkhead , just above deck level about 1ft square with what I assume was a plastic drain through it, over the coming days , a new piece if ally complete with assembled pipework was back in place & welded up.

[Rod]

Rod, have belatedly looked at this topic, & wish to (very nicely) contradict you, we were onboard QE2 in 2007, on 1deck, stbd side to the right of the Pavillion was a room , showers & changing;  my memory fails me here, but, there might 've been another small room aft of  it, used for storing towels & misc bits, there might not , I really am uncertain, however the crew had cut a piece of ally bulkhead , just above deck level about 1ft square with what I assume was a plastic drain through it, over the coming days , a new piece if ally complete with assembled pipework was back in place & welded up.

Pete, you are not contradicting me! You saw this in 2007. I left in very late 88. 18 years.  Welding technology and simplicity had come on so much.
When the welding schools were started, that was the way of the future....as was the QE2 and so much in her. But, when the ship was built, and for much of MY ship lifetime, Ally welding was not available, without much specialised equipment and training, that Cunard, ships bosses, whomever were not prepared to pay for. After our first Bayonne refit, and I saw what and how, I asked if we could get and carry, and of course for me to be trained, in similar equipment.... NO they said...what happens if you are on leave?
But  a similar story... the helicopter deck.
Somebody decided that they needed to "train" the pin pong paddle boys to land a helo....so they did... first helo to land..they were both on leave!

[Hank Hargrove]

It would be interesting to know how they handled that transition on the United States--despite her obvious woes she's nearly 60 years old and I've never heard of problems with the aluminum superstructure.

I think they used some sort of special tape between the steel and the aluminum. Then they welded it together. The ship has just been sitting around for the past 45 years, so it's hard to say. I've never heard anything either.

[Adam Hodson]

Thanks for that information Hank.

[Lynda Bradford]

When Rob was showing slides of the building of QE2, at the QE2 Story Event on 4 May 2019, there was a question regarding why the aluminium structure had been left unpainted for some time whereas the hull had been painted "as soon as possible".

George C Griffiths was good enough to get this explanation from a friend, an Industrial Chemist and Metallurgist who took time to write this easy to understand write up:

Even in the atmosphere an aluminium SURFACE is not metal but consists of a micro layer of aluminium oxide.
It is extremely difficult to paint and would require the use of special etching primers.
 
When joining it to a ship's hull you have the added problem that aluminium metal is extremely anodic to steel and would corrode very quickly. 
Naturally it would require to be wet or damp to do this.
Not really difficult on a ship!

The easy way out is to use a non-conducting layer between the steel hull and the superstructure. 
The steel hull must then be painted but the aluminium itself can be left alone for a time, as the micro layer of aluminium oxide (ref. above) will act like a layer of paint thereby protecting the base metal.
Eventually the aluminium would require to be coated for long life - by first using the etching primer (applied any way at all) and then the paint.
If the aluminium was painted without the use of this etching primer the paint would just flake off.

So in short - it is the natural presence of the micro layer of oxide that protects it and negates the need for coating/painting for some considerable time.