One's Brake Discs Are Not Shiny!

[ZZZZ]

How does one polish one's brake discs to a mirror shine?


LOL


Seriously though - I'm sort of used to see brake discs with pretty much uniformed silver shiny working surface. However, my recently (as in 1,650 miles ago) fitted MTEC Drilled and Grooved discs are not, particularly at close inspection - there are less shiny circles - not rusty, but still not as bright, as a section next to it.

The new pads (which were, of course, fitted at the same time) are OE Mercedes, and braking performance is excellent.

Is this down to individual's driving (braking) style, or combination of hardness of discs and pads, or something else? Should the pads be adjusted, perhaps?

 

[LostKiwi]

You can't adjust pads - they self adjust their gap to the disc.

A pic may make it clearer what you're seeing

 

[television]

Red ceramic pads and they will gleam, there is no sun today but you can see it Just back from a 400 mile very fast trip so wheels are not that clean.

 

[ZZZZ]

That looks perfect to me Malcolm, I guess I just had to wear the OE pads as fast as I can

Here's what I have:

I emphasised the effect a little bit in photoshop

I'll deal with the rust once it's warm enough outside to put some Hammerite on ...

 

[LostKiwi]

Automatic car?
Stopped when discs are hot with the pad in one place will cause some discolouration as the pad will change the rate the disc cools and you may get some pad transfer from the last braking effort.

Doesn't look to bad to me. Some indication of pad material in the holes (which is not unusual) and some slight scoring of the surface (hard pads? soft discs?) and what look to be some inclusions in the surface on one photo but nothing I'd be concerned about.

 

[ZZZZ]

Automatic car?
Stopped when discs are hot with the pad in one place will cause some discolouration as the pad will change the rate the disc cools and you may get some pad transfer from the last braking effort.

Yes, the car is automatic. I do however, try to ease of the brakes and let it move a few inches, once stopped, precisely for that reason - so not to 'bake' the pads into the discs. I guess I have to pay more attention to this.

Doesn't look to bad to me. Some indication of pad material in the holes (which is not unusual) and some slight scoring of the surface (hard pads? soft discs?) and what look to be some inclusions in the surface on one photo but nothing I'd be concerned about.

Thanks, that's good to hear.

I noticed those inclusions too - just now, while editing the full size pic. That's one of the rear discs, I'll check the other one tomorrow...

Not sure if the discs are classed as soft, or in fact if pads are hard - the pads are Mercedes OE, I bought directly from MB; the discs are MTEC.

I suppose, once I dealt with the rust, it'll look much better anyway.

 

[star]

That's some wear and rust for 1600 miles?

 

[ZZZZ]

That's some wear and rust for 1600 miles?

Yes, absolutely! I don't know why MTEC does not care about their products, but it is not, in my opinion, a level of protection I would expect ... To be fair, I didn't select an optional [extra] coating, which was a mistake, but even then, there should be some basic anti-rust treatment.

I very much doubt my next discs will be MTEC, as much as I like the grooved and drilled version, and its braking performance. The visual aspect is an important factor, certainly for me it is.

 

[chardF]

I fitted Pagid to the front the top hat had a painted finish that's stayed good and not corroded.

The rears however (I can't remember the brand but from GSF) I found myself painting them after a few months.

 

[Rory]

my recently (as in 1,650 miles ago)

How long ago in time where they fitted, and do you only use the car now and again?

Mine look similar but the car only moves every couple of weeks, and even then it does a 400 mile motorway trip with very little braking.

We have two VW's in the household that are used daily for commuting trips and their discs are smooth and shiny.

 

[ZZZZ]

How long ago in time where they fitted, and do you only use the car now and again?

Mine look similar but the car only moves every couple of weeks, and even then it does a 400 mile motorway trip with very little braking.

We have two VW's in the household that are used daily for commuting trips and their discs are smooth and shiny.

I use the car daily, but most days it's only two short 5-mile round trips, with occasional 40-50 mile round trip on DCW. The only long trip these past four months was to Cornwall and back, about 550 miles.

Discs and pads were fitted just over four months ago.

Apart from visual appearance, what I am concerned with is uneven wear, as discs are, apparently, a bit soft, and the oxidised bits are obviously harder ...

 

[television]

This thread does bring up the question of what the formula/composition was used for these disc.

 

[ZZZZ]

This thread does bring up the question of what the formula/composition was used for these disc.

Can't find any meaningful technical spec on their website.

They certainly perform better than the (original?) discs the car had on, when I bought it.

 

[malcolm E53 AMG]

I bought some Mintex discs for a Focus a few years back and they went the same way. I think it's inferior quality steel and very unlikely to be the pads. I would get a few more miles out of them and renew, what you are seeing on the face of the disc is scoring which will only get worse and begin to affect stability under braking.

I don't bother with aftermarket discs and pads any more as surprisingly MB brake parts are more competitively priced than you think and I usually ask for 10% discount and get it

 

[television]

Can't find any meaningful technical spec on their website.

They certainly perform better than the (original?) discs the car had on, when I bought it.

The surface area has increased with that ridged surface.

 

[LostKiwi]

They aren't exactly expensive disks and whilst its not a given the old saying you get what you pay for springs to mind.
The surface on them does suggest they are pretty low grade metal.

 

[ZZZZ]

I've never used MTEC before, and was under impression these were premium brake discs ... you live and learn

 

[Steed]

They look quite worn to me for only 1600 miles

 

[ZZZZ]

Well, I took the car for a [longer than usual] drive today and used the brakes a bit more, than I normally do (as in less anticipation, more braking) - the change is quite noticeable:

I'm not going to change my driving style to keep the discs shiny, but equally am not going to worry about it, from now on either ...

 

[Rory]

You'll just wear your tyres out quicker!

The dealer slways acts all horrifed when they see my car but I figure the brakes are designed to stop the car when fully loaded from 150MPH so with just me in it, pootling around at 70 they should be fine. It stops straight and true and I can trigger the ABS on a hard stop. Passed MOT with no comment a couple of months ago.