OZ Ruote alloy composition?

[Giniw]

Hello,
Lately I must have encountered a pot hole because my left front wheel is a little bent ... (I suspect the right one is not fully round either)
Anyway, I know that an alloy wheel is often repairable.
I asked for a couple of quotes and it appears it's between 80 and 180 euros per wheel (straightening+paint).
The process seems relatively simple (plenty of videos on youtube, e.g. https://www.youtube.com/watch?v=ig8qqck7has) :
- mounting the alloy on a hub so that it can be turned and measured,
- heating the wheel to soften the alloy (in french "température de recuisson", in english "annealing temperature" maybe?)
- straightening the wheel with a little hydraulic piston
The videos I have seen don't show a final quench step, so I am wondering if they are doing it at all*.

So here is my question: does anyone have any experience or knowledge about all that?
Does anyone know the alloy composition of our OZ Ruote wheels?
Thanks in advance!

(*) Incidentally I have read that the aluminium quench effect is not immediate, and that the first hour let the aluminum nearly as soft as after annealing it ... So when the aluminium forming is straightforward, one can heat it, quench it and form it cold in a single step. Rather interesting in my own opinion

[Giniw]

(I sent an email to OZ earlier today ... I don't really expect an answer though )

[Giniw]

I haven't had an answer from OZ (yet? ( )) but I have continued my readings.
This weekend I had the opportunity to have a look at the back of one of my wheels, and there are several markings, one of them is 3205 A
From what I have read about aluminium alloys and also from a few OZ informations like that (http://www.ozracing.com/world-of-oz/tec ... 72-marking) I gather 3205 A is indeed the alloy designation.
So, if I am not wrong, our rims are made of 3000 series alumium (aluminium-manganese)
That means our wheels cannot be quenched. (And, incidentally the 3000 series have only moderate strength).
Basically, the 3000 series seems to be annealable, but then the only way to harden it is cold working. Not very convenient when it comes to refurbishing a wheel ...
More informations: http://www.alcotec.com/us/en/education/ ... uminum.cfm

Anyway, if I understand well, the only reasonable option may be to heat the wheel at less than the annealing or even recovery annealing temperature to get a temporary ease to straighten the wheel while not changing its metallic state — so the wheels have to be heated to (much) less than min(345°C, 250°C)= 250°C (http://www.euralliage.com/alliage.html#ancre669934)

Or maybe the recovery annealing state might be achieved locally where the wheel is bent to ease the straightening even more, the straightening being done at room temperature to allow the cold forming process to harden the wheel again.
That sounds nice but I think it would be nearly impossible to heat only a part to 250°C while the rest is kept cooler ...

Anyway ... To be continued ...

(I hope it makes sense — at least a little )

[tigerdog]

Great research. Thanks for sharing and keep the info coming - I have three egg-shaped wheels of my own that need to be fixed.

[steve matthews]

Had 2 Fed. wheels 16" out of round. Wheel Wizard straightened stripped and powder coated.
Told them they were OZ wheels they said they new how to work.
Powder coat ovens are at 450 deg. range.

5 years now and wheels are still perfect with minimal inner flat weights applied.

Steve

[dapinky]

Powder coat ovens are at 450 deg. range.

Whilst you may be correct - as you're on the wrong side of the Atlantic you may be confusing Celcius with Farrenheit

Powdercoat 'melts' at 150C and cures at 200C (400ish F)

[Giniw]

Interesting remark about the powder cure temperature, which indeed means it's safe at least for a short moment — does anyone happen to know the time needed to cook a powdercoat?

Steve > Do you happen to remember what was the price range? I know it was 5 years ago but still I am curious if the prices are more or less the same than in France.

[dapinky]

does anyone happen to know the time needed to cook a powdercoat?

When my wheels were done, I was told it was 10 minutes in the oven, then cooling in a controlled environment, so the whole process was about an hour.

[steve matthews]

teve > Do you happen to remember what was the price range? I know it was 5 years ago but still I am curious if the prices are more or less the same than in France.

$125.00 U.S. each.

Steve

[Giniw]

Thank you! A little cheaper then, but of course it was 5 years ago, so I would say it's in the same price range.

Anyway, I started a little modelling tonight.
Basically, I only needed the bounding cylinder but I think at some point I lost control (still far from perfect and not really to scale since I don't have the measurements here but that will be fixed later)

ruote_se.png

ruote_se_back.png

ruote_se_front.png

[Giniw]

As I have modelled my wheel yesterday I thought it could be funny to try to do some finite element analysis to it ( )
This is just a fake loading so far since I don't known much about all that but I will try a proper one when the wheel is really fully modelled (scale, etc)

file3_575b385c.jpg

(actually I am trying all this because it will be useful when I will do the dimensioning of my tooling if ever I decide to do it)

[Giniw]

Well, so far I conclude that I rendered my wheel in pretty colours ( )
(Still, the wheel is now modelled to scale and I managed to make more realistic loadings although this particular one is huge — the wheel would have broken in real life)

[Giniw]

Right, there is still room for improvement, but at least I have begun to "design" my "tool" ( ) (I guess it's probably a terrible way to put the vertical beam onto the IPN, I will search for a better way to get a good structural rigidity — maybe just a 45° cut?)

Clipboard01.png

(OK I admit it was not absolutely necessary to draw the disc, but hey, I needed a spacer and I still have my used ones!)