Interesting, magnesium is a lot lighter so I do wonder how they can do that - unless it will be using less material?
I profess to not knowing much about alloy wheel creation!
This is one of the things which was discussed.
Our wheels are cast magnesium, and would have been cast in such a way as to make the manufacture vaguely cost effective. They would have also had to make the wheels stronger as a roadwheel, and also added more material in certain places as apparently magnesium wheels lose strength over time. It's highly unlikely that OZ Racing still have the casting from our wheels, so for them to make another production run would require a new casting (€25,000 or more).
Hence OZ Racing needing a decent production run to make the numbers viable.
Making an aluminium wheel from billet (forged) rather than cast makes them 25-30% stronger OR lighter than an equivalent cast aluminium wheel. Given that the specific density of aluminium is 35% higher than magnesium you quickly get to the point where a CAST magnesium wheel can end up and barely any lighter than a FORGED aluminium wheel... although making forged wheels is expensive because the CNC machines are hideously expensive and the waste material from machining the billet is enormous.
Now the other thing is that once you have created a replica wheel in CAD and told the CAD you're using aluminium it can calculate the volume of material and therefore the weight of the finished product - before you actually start cutting a wheel.
And of course the CAD program can calculate stresses and strengths.
Given that a fully loaded Aero is topping out at 1400kg (with two people, fuel, and luggage) the wheels don't need to be as strong as a 9x18 wheel used on a 2.5 ton SUV for example.
I am excited that we might all soon have a sensible long term solution - wheels that are similar in design and weight to the originals but are less brittle and also able to be repaired by ANY alloy wheel specialist.
I hope to have more information in the next month or so. Watch this space.
