Spray painting brake discs?

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Emm3
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Mon Jan 02, 2012 2:16 pm

I have a problem with my car when it's parked over the winter in that the discs end up orange all over with surface rust. I came across this topic on a mustang forum in the states and one guy sprayed the whole disc red to match his calipers the idea is that when the car is driven the pad wears away a clean section and the remainder stays painted not a bad idea I think especially to stop them rusting quick? I'm not sure what effect the dried paint would have on the pad or if it would affect it
E30BeemerLad
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Mon Jan 02, 2012 2:19 pm

Wouldn't bother mate, as soon as you apply the brakes it will take off any surface rust.

I wouldn't like to find out how effective (or not) the brakes would be with the paint on, sounds like a stupid idea.
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Emm3
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Mon Jan 02, 2012 2:24 pm

I bought some black diamond discs for an old v dub and I could swear they were painted matt black the face and the vented part stayed black and the only part that rusted was where the pad met the disk
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Mon Jan 02, 2012 2:30 pm

A thin coat from a rattle can wouldn't affect braking too much, as it would rapidly be worn through.
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Mon Jan 02, 2012 3:08 pm

Speedtouch wrote:A thin coat from a rattle can wouldn't affect braking too much, as it would rapidly be worn through.

Sounds like a lot of ballache for almost no reward!!!!!!
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Mon Jan 02, 2012 3:13 pm

Maybe if you did it straight from the box, when the discs were brand new, but otherwise painting the disc will offer zero protection from rust while also clogging up your pads.

A fool's task if ever there was one.
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Mon Jan 02, 2012 3:51 pm

Grrrmachine wrote:Maybe if you did it straight from the box, when the discs were brand new, but otherwise painting the disc will offer zero protection from rust while also clogging up your pads.

A fool's task if ever there was one.
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Speedtouch
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Mon Jan 02, 2012 4:43 pm

Another way of reducing the rusting is to place bags of salt/rice or silica gel next to them.

Alternatively, ensure that the car is moved back and forth every month or so.
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Mon Jan 02, 2012 4:47 pm

break discs can start rusting when parked un driven for 2 weeks, ive left my e30 parked up all last winter for 3 monthsm took my sport out round the block today after 2-3 months, all you need to do is drive a few yeards, break, reverse, break, a few times before driving off and just break a few times and they are back to normal

painting them sounds stupid to me
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Mon Jan 02, 2012 5:12 pm

brake discs show a bit of rust after washing the car so dont worry about it....

interefering with the braking system by painting the discs must be an MOT fail? or if not, just plain NUTS....if the braking just takes away the top layer of paint, then this means instead of braking using the brake pad against the disc, you are just using the brake pad against the paint which wont stop the car....that mustang owner must be high 8O
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Mon Jan 02, 2012 5:45 pm

Pagid and a few other mfrs do paint the "bell" and outside diameter of some discs, but there's not much point.

Black Diamond might have used flame plating for the black stuff, that'll look like spray-paint (in fact I wonder if Pagid do too?).

DIY? Nah.
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Mon Jan 02, 2012 6:55 pm

painting them is pretty pointless - unless u drive like miss daisy any paint that is anywhere on the disc (even where the pad doesn't contact) will just get burnt off with the heat.

as said discs can rust even overnight - if you're super bothered try just wiping them with a light oil (which is how they come when new) and then give them a wipe with solvent before you drive it again - obviously try not to get it on the pads.
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Mon Jan 02, 2012 7:17 pm

keri-WMS wrote:Pagid and a few other mfrs do paint the "bell"
The only 'bell' here is the mustang owner! :)

Also the paint will fall off due to the temperature of the discs after braking.. Ridiculous..
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Mon Jan 02, 2012 7:56 pm

Emm3 wrote:I have a problem with my car
No, you don't!
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Mon Jan 02, 2012 8:09 pm

Black diamond discs have somekind of finish that keeps them black, hence the name.

When I changed the discs on my Leon I had some high temp clear coat kicking around I sprayed the centres and the vents but covered the braking service, has kept them looking a bit fresher for longer. The braking service shows survive rust within an hour of being parked up if it's raining.
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Mon Jan 02, 2012 10:05 pm

diable wrote:Remove the disks from the car and store them at home.

1 It will stop them going rusty
2 If someone steals your car then you'll know about it pretty quick

or just soak them in snake oil :mad:
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HairyScreech
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Thu Jan 05, 2012 3:31 pm

the pagid stuff comes coated/painted now does it not?

did chuck a light coat of paint over the cossie brakes on the ka, the driving required to get it on and off a trailer took all the paint off, so literally about one 5m application of the brakes and it was off, no apparent detriment to the brake effort or the pads.
i just brushed on a very thin coat of black paint.
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Demlotcrew
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Thu Jan 05, 2012 4:26 pm

Obviously all of the slaters in this thread have never bought genuine disks for their cars, they would otherwise know that BMW coats all their disks in zinc primer to stop corrosion of the disks.

Its not a stupid idea,

To make the most of it i would

1. Remove the disks for painting.
2. Push back the pistons in the callipers so the pads are not touching the disks.
breakermart
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Sun Jan 08, 2012 10:13 pm

have you lot realy just had that conversation lol WOW. 8O just leave them alone. works fine for the rest of the world, dont you agree? next youl want to paint the tops of your engine pistons because they look sooty lol. :mad:
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Mon Jan 09, 2012 9:35 am

Actually i have been told using high temp paint on the crowns of piston during build can have the advantage of the paint behaving like the carbon layer and thus allowing accurate tuning from the kick off rather than having to wait for the engine to carbon in, it will sublime and give similar fuel wetting and heat blocking properties to the carbon layer. its not a whole lot of use for a normal car but for something with very limited running time like drag engines etc then it can
help squeeze a little more life from them.
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breakermart
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Tue Jan 10, 2012 10:31 pm

HairyScreech wrote:Actually i have been told using high temp paint on the crowns of piston during build can have the advantage of the paint behaving like the carbon layer and thus allowing accurate tuning from the kick off rather than having to wait for the engine to carbon in, it will sublime and give similar fuel wetting and heat blocking properties to the carbon layer. its not a whole lot of use for a normal car but for something with very limited running time like drag engines etc then it can
help squeeze a little more life from them.
well that just p**sed on my fire lol you could have just not said anything :o:
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Tue Jan 10, 2012 10:50 pm

breakermart wrote:
HairyScreech wrote:Actually i have been told using high temp paint on the crowns of piston during build can have the advantage of the paint behaving like the carbon layer and thus allowing accurate tuning from the kick off rather than having to wait for the engine to carbon in, it will sublime and give similar fuel wetting and heat blocking properties to the carbon layer. its not a whole lot of use for a normal car but for something with very limited running time like drag engines etc then it can
help squeeze a little more life from them.
well that just p**sed on my fire lol you could have just not said anything :o:
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Tue Jan 10, 2012 10:52 pm

lol like it.
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Tue Jan 10, 2012 10:59 pm

Paint is a waste of time, ive tried it and it just burns off if you use the car properly, perfect for the concourse bufties that trailer their cars everywhere :)

Rusty discs are nasty though especially if you have great big fook off ones behind the wheels, when I did my brake upgrade I had the discs zinc plated and its worked very well, the zinc soon came off the friction area and keeps everywhere else nice and silver 8)

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Emm3
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Tue Jan 10, 2012 11:35 pm

DanThe wrote:Paint is a waste of time, ive tried it and it just burns off if you use the car properly, perfect for the concourse bufties that trailer their cars everywhere :)

Rusty discs are nasty though especially if you have great big fook off ones behind the wheels, when I did my brake upgrade I had the discs zinc plated and its worked very well, the zinc soon came off the friction area and keeps everywhere else nice and silver 8)

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How much did it cost to zinc plate?

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Tue Jan 10, 2012 11:45 pm

Emm3 wrote: How much did it cost to zinc plate?
Depends how much you take to have done at the same time, but generally about a tenner a disc
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Thu Jan 12, 2012 12:24 am

Dezzy wrote:
breakermart wrote:
HairyScreech wrote:Actually i have been told using high temp paint on the crowns of piston during build can have the advantage of the paint behaving like the carbon layer and thus allowing accurate tuning from the kick off rather than having to wait for the engine to carbon in, it will sublime and give similar fuel wetting and heat blocking properties to the carbon layer. its not a whole lot of use for a normal car but for something with very limited running time like drag engines etc then it can
help squeeze a little more life from them.
well that just p**sed on my fire lol you could have just not said anything :o:
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it was more wjust for the lols, but it is actually something that is apparently done.
ow if you will excuse me i have to go paint my windscreen, its full of little scratches and i think it would look much better body coloured.
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Thu Jan 12, 2012 2:32 am

I reckon the "grease em" idea was the best, but how do I get Hammond or Clarkson to drive it first??
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Thu Jan 12, 2012 11:32 am

I knew a guy who used to wax his windscreen to make the water bead and run off (instead of using his wipers!)....
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Thu Jan 12, 2012 2:05 pm

keri-WMS wrote:I knew a guy who used to wax his windscreen to make the water bead and run off (instead of using his wipers!)....
I use this german stuff which pretty much does the same!

Andrew
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Thu Jan 12, 2012 2:13 pm

Demlotcrew wrote:
keri-WMS wrote:I knew a guy who used to wax his windscreen to make the water bead and run off (instead of using his wipers!)....
I use this german stuff which pretty much does the same!

Andrew
Ah,
The flipemflopempreventemstopen wax..... :D
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Thu Jan 12, 2012 3:46 pm

As an ex biker, I have seen for myself that higher quality brake discs, have a higher iron content in them so they grip better. Where it's obvious on a bike, race spec discs will pretty much rust up over night due to the iron in them. Ones that don't rust are all steel and won't stop you as well.

The only thing I would worry about is if they are left for months and months it is possible for the rust to go deep enough that when it is cleaned off by driving, it will be pitted underneath, but that just means you need to take it for a spin every few months. If it's stationary for longer than that, presumably the reason is it's in bits, so just take them off and store them in oil.
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Thu Jan 12, 2012 3:56 pm

mattycoops43 wrote:As an ex biker, I have seen for myself that higher quality brake discs, have a higher iron content in them so they grip better. Where it's obvious on a bike, race spec discs will pretty much rust up over night due to the iron in them. Ones that don't rust are all steel and won't stop you as well.

The only thing I would worry about is if they are left for months and months it is possible for the rust to go deep enough that when it is cleaned off by driving, it will be pitted underneath, but that just means you need to take it for a spin every few months. If it's stationary for longer than that, presumably the reason is it's in bits, so just take them off and store them in oil.
This is exactly why i run a massive dehumidifier in the garage.

Andrew
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Thu Jan 12, 2012 9:48 pm

Its the damp that does it, my car has been up in the air on a lift since end of November and the discs just have a light dusting of powder type rust, if it was on the ground they would be a lot worse.
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