Alpha omega racing bracket

[drifter17a]

Back in 2016 bought a set of front and rear bracket set and changed all 4 corner discs and caliper

 

i was checking the car and seen rust like or in another word crumbled part of the bracket which came off with a air blow

 

is this normal? This had happened in two areas and car from 2016 has mostly been in garage/ doing less than 2000 miles over past 8 years or so

pic with areas highlighted in red

 

https://ibb.co/NtmWXZt

 

also anyone knows the torque spec for the bracket as want to retorque them, one bolt had come off half way !

 

[GTSBoy]

Um...that thing looks terrible. I'd be looking for replacements tout de suite. WTF is it made of? Die cast cardboard?

[drifter17a]

Checking with alpha omega

 

Spec from their website 

• 100% CNC machined billet 7075-T6 aerospace alloy

 

https://www.alphaomegaracing.com/product/evo-350mm-brembo-brakes/

[GTSBoy]

Well, they really shouldn't rot like that. Have you been driving over spilled caustic soda or something?

[drifter17a]

No i am in the uk so maybe road salt etc but checked rear and same story where handbrake cable seems to have eaten part of the bracket. Have emailed alpha omega waiting for reply

[drifter17a]

Here is picture of the rear brackets again seeming to have eating itself or corrode or whatever. Can’t describe it , hope someone could explain this

 

 

[GTSBoy]

Dissimilar metal corrosion. Aluminium is less noble than steel/iron, and will corrode preferentially when in contact with it and a conductive solution (ie, wet road salt).

Tends to suggest that those brackets should be made in steel for a shitty climate like the UK.

[drifter17a]

So unsafe would you say now?

 

little bit of has come off, guess road salt is a nightmare for Japanese car. Mx5 here have a well known issue or rotting 

[GTSBoy]

21 minutes ago, drifter17a said:

guess road salt is a nightmare for Japanese car

'Sgot nothing to do with them being Japanese. The climate in the north of Japan has similarities to the UK - the cars are made in the knowledge that they have snow and salt, and they rot there. Cars made in the US rot like buggery in the US. British cars have always rotted regardless of the weather. They will rot indoors in a climate controlled bubble!

The brackets are not unsafe yet, but they will get that way. They may well corrode where the bolt threads are in contact and the bolts could just jump out without warning.

[drifter17a]

Thanks

 

does painting on aluminium work or stop them from corroding?

[GTSBoy]

10 minutes ago, drifter17a said:

does painting on aluminium work or stop them from corroding?

Yes, but no. You need to keep the mating surfaces bare (ie the flat faces where the caliper and upright pads touch the dogbone) and also the internal threads will remain bare (unless there are no internal threads - do they use nuts on all the bolts?). So you can slow down obvious external corrosion, but not all of it.

Anodising would be required to provide decent protection to the alloy, but I'm not actually sure if you should anodise something that is all about the strength. Anodising does reduce strength significantly. Like, up to 50% on some alloys for high thickness coating.