as far as I am aware Gazza, the same way the sea is influenced by the magnetic pull of the two poles and the sun causing low tide and high tide, I would assume that this would be relatively the same sort of thing. it is an effect that occurs with many structures that are tall, but not necessarily hevily reinforced... namely towers without lots of cabling support.

Hahahaha, Alex that’s the funniest thing I have heard. Could that mean you are wrong yet again? It has nothing to do with a magnetic or gravitational force. When metal is heated the atoms get excited and vibrate further apart which causes the metal to expand. This is why the tower would bend. At night time since the sun is gone, they can take it down safely.

I though it was because during the day the structure is subject to heat which would cause the structure to expand. So do structures really move toward the sun? And for what reasons? Is Alex correct?

the heat would cause the metals to expand, but im not inclined to leave it at that, as the heat would expand the metal, but it doesnt explain why the tower itself LEANED towards to sun. Giving it further thought, its quite possible it might simply be that it leans towards the side that the sun is on because that side is heated while the other side is in shadow, leaving a bendable side closer to the sun and a rigid side away from the sun, which would cause it to tip towards the sun... yeah - thats probably an ockhums razor solution to the problem.

Actually if that was the case it would bend away from the sun. As the side in the sun would expand causing it too lean away from the sun.

not necessarily. a non-expanded piece of metal will have more rigidity, and prevent the tower from leaning that way, however the expanded metal will be weaker. it will not push up, causing the tower to lean the other way, rather it will become weaker, and allow more flexibility, allowing the tower to lean towards the weakened side because of the loss of rigidity in the metal. Just because it expands, it doesnt mean it will expand UP.

I'm not arguing about anything that's been said, but that's probably the weirdest thing I've heard all week!

as far as I am aware Gazza, the same way the sea is influenced by the magnetic pull of the two poles and the sun causing low tide and high tide, I would assume that this would be relatively the same sort of thing. it is an effect that occurs with many structures that are tall, but not necessarily hevily reinforced... namely towers without lots of cabling support.

You are an IDIOT! The sun and the magnetic pull of the poles have absolutely NOTHING to do with the tides. If you actually listened during science in High school you would know that the tides are caused by the motion of the moon

The tower can easly be taken down in the day. So if the tower moves how come the ride can still operate in the day?Wouldnt the track get a bend/twist in them and cause the godulas to get "stuck".

Willsy, Steel expands much like many things during the day. While its largely unnoticable (Roads expand in the heat too), the minute movements release and apply pressure on joins, such as where the Sp tower is bolted together. The movements are incredibly small, but obviously enough to warrant removing the tower at night. I would imagine that a dark black tower also wouldn't be the coolest of things to have your hands all over during a hot day either

As far as I was ever aware it was the dome that moved, not the whole friggin tower following the sun... That sounds dicriculous to me... Take note of the angle of the tower next time you drive past, and have a look at the slant the dome is on. You'll also note its postition will vary depending on the time of the day. Good old Mr Tower doesn't move with it you dolts! Yes it expands, hence the reason for nightwork, but it's as straight as a die.

Just because it expands, it doesnt mean it will expand UP.

I am pretty sure it would expand uniformly. Why would it not expand up?

The tower [Eiffel Tower] may also lean to one side under the influence of sunlight. The sunlight heats one side of the tower and it expands, tilting the tower. Here again, the magnitude of the movement is never more than eight to twelve centimetres. This is a tilt, not a sway, and the tower remains tilted until the sun goes down. It follows a very regular pattern throughout the day, if the sun is shining.

The tilting of a tower in the sunlight is from expanding metal, not weakened metal that bends.

People the tower does not bend, tilt, move or what ever, I have been in the metal industry for years.

Maybe the hat appears to move because of the shadows being cast.

Willsy, while respecting your opinion on metallurgy, the quote regarding the eiffel tower tends to explain our theory. You work with metal, but have you worked with a metal structure that is over 210 feet tall, and about 200 centimetres (or maybe a little more) diameter, hollow, with moving parts running up and down the outside AND inside of the structure, a lot more weight on top of it, on top of a big exposed hill out in the elements?

Why would it not expand up?

Get a balloon, and apply weight to the top of it. which way does the balloon expand? Get a bottle of water, filled to the cap, screw the cap on tightly and freeze it, lying on its side... which part of the bottle breaks first under the pressure? When something expands, it will expand in the direction of least resistance. As there is 1 atmosphere (sea level) of air all around the tower, but there is the REST OF the tower above it, and on top you have the hat, electronics, transmission gear and a lot of other stuff, you have 1 atmosphere plus - lets say 1-2 tons. the direction of least resistance would be outward. Now heated metal expands, and expanded metal is less dense, and therefore more pliable than cold or non-expanded metal, and is therefore more flexible. the cooled side would remain rigid, while the heated side would expand OUTWARDS and the walls would be weaker because of their enhanced flexibility, which would cause the tower to lean TOWARDS the sun.

The problem they would have had during construction was the sections of tower misaligning with each other and that is why it was done at night. Next time you are on a train look at the tracks next to you. If you are in Sydney this shouldn't be a problem as the trains have a nasty habit of stopping for no reason. Every so often there is a gap in the track, the gap is about an inch wide, and as the heat increases the gap gets smaller. If it gets too hot, over 35C usually, the tracks will start to bend because the gaps have gone and the metal has to expand somewhere. "The Bus is now leaving for The Little Gap, NSW"

Maybe the hat appears to move because of the shadows being cast.

Ahhh yes, that's what it is! Of course!...

Who thinks the metal bends from weakening which causes the tower to bend? Or who thinks the tower "bends" the same way as the Eiffel tower from one side expanding?

i believe that the metal does expand and contract, but i dont believe that you can see it doing that, for there to be enough degrees of lean the tower would need to be at least 5-10 degrees off straight ...now thats alot for a tower that size. One other thing is that metal conducts heat quite well and the tower although one side is heated the other side would have either heated earlier in the day when the sun was in a different position and also heated through conduction of heat

Adam, dont get me wrong, i still agree with you on the subject that the expansion causes the lean, i just think it would lean towards the sun, not away from it - and that is because of the weakened steel.

The 'bend' on Space Probe was not visible and I think it would have been in the range of 1-5 degrees. Although it is not very much it was enough to force the construction of the tower to be moved to the night. I often stood inside the launch area looking directly up and the tower and it appeared to sway but that was because it is difficult to stand on the spot and look straight up at something in the distance and be able to keep your balance. "The Bus is now leaving for Balancing Rock Creek, South Australia"

It's just your vertigo Bus old son. Don't worry about it.... One time, he stood there mid cycle and started day dreaming. I had to crash tackle the silly bastard!

I am going to stay outof this one. I have been mentioned enough already as it is.

One time, he stood there mid cycle and started day dreaming. I had to crash tackle the silly bastard!

I can neither confirm or deny this recollection. "The Bus is now leaving for Collector, NSW"

Take it from me guys, since Im probably the only one here who has actually been up in the Space Probe hat, many times, for long periods, and always at night. It moves, just like any tall structure. ZordMaker