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any disk brake equipped - Coke can for brake disks - edlithgow

Coke cans for Brake Disks.

Not actually AS brake disks, but to clean them up a bit.

Exhibit A : Drivers side front hub and brakes.

[url=www.servimg.com/view/18149521/126][img]i18.servimg.com/u/f18/18/14/95/21/th/img_5110.jpg[/img][/url]

I put the foil on the hub a couple of years ago to stop the wheels rusting on. Seems to have worked, but of course the remains look messy. The rusted remains of a shim have displaced and are stuck against the disk boss. The brakes don't squeal and I probably wouldn't care much if they did, so I probably don't need shims.

Exhibit B : During cleanup.

[url=www.servimg.com/view/18149521/127][img]i18.servimg.com/u/f18/18/14/95/21/th/img_5111.jpg[/img][/url]

Other wheel is chocked and the engine run in second gear. (higher gear might have been better but wasn't sure the diff would like it.) Coke (or beer) can top/bottom (or whole thing crushed) is forced against the disc rim. Whole can crushed has more material but is a bit grabby and top or bottom is probably safer. You could easily get your hand mangled doing this, and it might have been smarter to hold the can section with mole grips.

I wore eye protection but no breathing or hearing protection, both of which would probably have been a good idea. Stray dogs cleared the area as soon as I started.

Exhibit C: Disk after cleanup (this is actually the other side)

[url=www.servimg.com/view/18149521/128][img]i18.servimg.com/u/f18/18/14/95/21/th/img_5112.jpg[/img][/url]

Exhibit D: "Tools"

[url=www.servimg.com/view/18149521/129][img]i18.servimg.com/u/f18/18/14/95/21/th/img_5113.jpg[/img][/url]

The bits of TV ariel were used for the side of disk boss, You CAN get a can in there but it feels too risky.

Exhibit E : Caliper guide pin before cleanup.

[url=www.servimg.com/view/18149521/130][img]i18.servimg.com/u/f18/18/14/95/21/th/img_5114.jpg[/img][/url]

Exhibit F : Caliper parts after cleanup

[url=www.servimg.com/view/18149521/131][img]i18.servimg.com/u/f18/18/14/95/21/th/img_5115.jpg[/img][/url]

I don't know if the "shinyness" on the disk edge is clean steel or adherent aluminium. The latter would be better from a corrosion reistance perspective but I'd guess its a bit of both.

Clearly the steel is still pitted, and it would take a very long time to remove the pits. I'm not using any binder for the aluminium here, because I'm concerned about contaminating the pad surfaces, but that would probably help fill the pits and I might try it. Superglue would probably be safest in this application, but it'll likely burn off, as would anything else I can think of except maybe ceramics.

I've tried various tricks to clean up brake disks for the UK MOT. None of them worked, and this probably wouldn't either, but it looks more promising than anything else I've tried. Electrolysis would probably be better but I don't have to pass an MOT any more so I havn't bothered to set that up.

(There were traces of what was probably very old hardened copaslip on the stainless slides, the pad backs, and perhaps some contamination of the pads. I cleaned this off (initially under water) with coke can, foil, scraped the pads with a razor blade, boiled them, dried them off, and then used brake cleaner on them, and they look a lot better, but of course you cant really get all that stuff off.)

any disk brake equipped - Coke can for brake disks - bolt

Would it not have been easier to replace the parts, what you`ve done dont look too clever to me?.

Nothing like doing the job properly!

any disk brake equipped - Coke can for brake disks - RobJP

Would it not have been easier to replace the parts, what you`ve done dont look too clever to me?.

Nothing like doing the job properly!

And that, as my grandad would say, is nothing like doing the job properly !

any disk brake equipped - Coke can for brake disks - bolt

??????

any disk brake equipped - Coke can for brake disks - focussed

You might at least try to bodge it properly like this:-

www.youtube.com/watch?v=RdMFpuLCcxA

any disk brake equipped - Coke can for brake disks - Wackyracer

You might at least try to bodge it properly like this:-

www.youtube.com/watch?v=RdMFpuLCcxA

Good to see it ran nice and true when he 'flipped it around' :) I bet they were under minimum thickness before he started.

any disk brake equipped - Coke can for brake disks - edlithgow

You might at least try to bodge it properly like this:-

www.youtube.com/watch?v=RdMFpuLCcxA

Good to see it ran nice and true when he 'flipped it around' :) I bet they were under minimum thickness before he started.

Well it seems to have worked. I find that a bit relevant, but then I can't visually assess disk thickness off a youtube video.

That do seem too clever to me.

He's cleaning/levelling the disk surface though, which I'm not attempting.

I doubt a coke can would be effective (and maybe not safe, disk contamination-wise) in that role, and I don't have an angle grinder or ready access to electrical power to do what he did.

I think I tried wire brushing under engine power alone to clean the disk face in the Yook but it wasn't effective.

I suppose an oil stone used with water might work, and have a levelling effect, but it'd have to be a new one, (because of the oil) and it might not be much good for anything else after.

Maybe a brick? :)

any disk brake equipped - Coke can for brake disks - gordonbennet

You might at least try to bodge it properly like this:-

www.youtube.com/watch?v=RdMFpuLCcxA

That's not actually a bad way to do it, assuming you're really stony broke, however when he turns the disc around and its wobbling like billio he must have intruouced some high and low points to the inside of the disc face.

Not something i'd be doing anyway, some years discs weren't quite so cheap as they are now, especailly for some foreign cars, my Renault 21 discs were badly scored so got them lathed down, within a short period a horrible pulsing could be heard and felt, one of the discs had cracked, never tried that again.

any disk brake equipped - Coke can for brake disks - John F

You might at least try to bodge it properly like this:-

www.youtube.com/watch?v=RdMFpuLCcxA

Excellent. I use the carborundum wheel I inherited from my father decades ago. Those discs look old, but not much used. If keeping a car for a long time it is important not to replace discs and pads until they are well worn, otherwise the pistons never travel far along the caliper cylinder which, unprotected by brake fluid, will tend to corrode, necessitating earlier and much more expensive caliper replacement when the pistons seize. The MoT serves nicely as a check on brake function.

any disk brake equipped - Coke can for brake disks - edlithgow

Would it not have been easier to replace the parts, what you`ve done dont look too clever to me?.

Nothing like doing the job properly!

No, it would not.

In The Yook I had to replace disks annually, for each MOT, due to" visible rust", though the cars passed the brake function test fine. This was perhaps because I didn't drive much, and when I did it was in salty Scotland.

Never headan justification for that other than "because we say so".

I tried swapping the shiny disks out after the MOT with a view to using them again for the next one, but I think that only happened once or twice, due to the cars (bangers) being replaced in the interim.

Here I don't have to do that, so I'm damned if I'm going to. Parts for this car are hard to find (though disks might be OK, havn't tried) and I have to organise Chinese translation, which is a pain.

Other than that "It don't look too clever to me" is too vague a criticism to worry about, and difficult respond to.

Maybe "There's no accounting for taste?"

any disk brake equipped - Coke can for brake disks - edlithgow

Would it not have been easier to replace the parts, what you`ve done dont look too clever to me?.

Nothing like doing the job properly!

No, it would not.

In The Yook I had to replace disks annually, for each MOT, due to" visible rust", though the cars passed the brake function test fine. This was perhaps because I didn't drive much, and when I did it was in salty Scotland.

Never heard a justification for that other than "because we say so".

I tried swapping the shiny disks out after the MOT with a view to using them again for the next one, but I think that only happened once or twice, due to the cars (bangers) being replaced in the interim.

Here I don't have to do that, so I'm damned if I'm going to. Parts for this car are hard to find (though disks might be OK, havn't tried) and I have to organise Chinese translation, which is a pain.

Other than that "It don't look too clever to me" is too vague a criticism to worry about, and difficult to respond to.

Maybe "There's no accounting for taste?"

any disk brake equipped - Coke can for brake disks - skidpan

Simple facts:

Brake discs are not expensive.

Having good brakes is safety critical.

If you are not prepeared to maintain your car correctly don't drive.

How would you feel if your bodge ended in an accident that killed someone.

That would leave you facing prosecution and you would have to live with the simple fact your poor maintenance was a factor.

For pities sake buy new discs.

any disk brake equipped - Coke can for brake disks - bolt

Would it not have been easier to replace the parts, what you`ve done dont look too clever to me?.

Nothing like doing the job properly!

No, it would not.

In The Yook I had to replace disks annually, for each MOT, due to" visible rust", though the cars passed the brake function test fine. This was perhaps because I didn't drive much, and when I did it was in salty Scotland.

Never heard a justification for that other than "because we say so".

I tried swapping the shiny disks out after the MOT with a view to using them again for the next one, but I think that only happened once or twice, due to the cars (bangers) being replaced in the interim.

Here I don't have to do that, so I'm damned if I'm going to. Parts for this car are hard to find (though disks might be OK, havn't tried) and I have to organise Chinese translation, which is a pain.

Other than that "It don't look too clever to me" is too vague a criticism to worry about, and difficult to respond to.

Maybe "There's no accounting for taste?"

I was being polite and could not believe what you had done, I still find it hard to believe someone could be that dumb as to bodge like that,

so as for criticism thats puting it mildly, where you are, at least I wont be driving near your car but I feel sorry for anyone that has to

any disk brake equipped - Coke can for brake disks - edlithgow

Would it not have been easier to replace the parts, what you`ve done dont look too clever to me?.

Nothing like doing the job properly!

No, it would not.

In The Yook I had to replace disks annually, for each MOT, due to" visible rust", though the cars passed the brake function test fine. This was perhaps because I didn't drive much, and when I did it was in salty Scotland.

Never heard a justification for that other than "because we say so".

I tried swapping the shiny disks out after the MOT with a view to using them again for the next one, but I think that only happened once or twice, due to the cars (bangers) being replaced in the interim.

Here I don't have to do that, so I'm damned if I'm going to. Parts for this car are hard to find (though disks might be OK, havn't tried) and I have to organise Chinese translation, which is a pain.

Other than that "It don't look too clever to me" is too vague a criticism to worry about, and difficult to respond to.

Maybe "There's no accounting for taste?"

I was being polite and could not believe what you had done, I still find it hard to believe someone could be that dumb as to bodge like that,

so as for criticism thats puting it mildly, where you are, at least I wont be driving near your car but I feel sorry for anyone that has to

Still no explanation as to how removing rust from the disk rims (and cleaning up the caliper parts) is going to interfere with brake function.

The car passed the six-monthly govt inspection brake function test about 5 months ago, with its brakes in probably almost the visually fairly sorry state in the first picture, though the recent typhoon soaking has apparently speeded up rust on exposed metal, like brakes and exhaust manifold.

Its due another inspection in about a month. They don't do much visual inspection/testers discretion stuff, but they test what you can measure and automate, like brake function, lights, emissions.

I cant see why it would be the worse for this treatment, even if it isn't any better, but we'll see.

any disk brake equipped - Coke can for brake disks - RobJP

I think the question from those sceptical is : what evidence is there to show that you've made any improvement to brake function by removing that rust from the brake rims and cleaning up the caliper parts ?

You've just stated that the inspection doesn't really matter regarding visual (i.e. the look of) the brake components, but rather measures the function of the components. What evidence do you have to show that your 'repair' actually has any beneficial effect whatsoever ?

The simple fact is that, as another person has stated, brakes are a safety-critical component. Therefore, someone who doesn't really know what they're doing, messing about with them to make them 'look better', is probably not recommended.

any disk brake equipped - Coke can for brake disks - edlithgow

I think the question from those sceptical is : what evidence is there to show that you've made any improvement to brake function by removing that rust from the brake rims and cleaning up the caliper parts ?

You've just stated that the inspection doesn't really matter regarding visual (i.e. the look of) the brake components, but rather measures the function of the components. What evidence do you have to show that your 'repair' actually has any beneficial effect whatsoever ?

The simple fact is that, as another person has stated, brakes are a safety-critical component. Therefore, someone who doesn't really know what they're doing, messing about with them to make them 'look better', is probably not recommended.

Again, that's not a substantive criticism, just an attempt at generalised put-down, which this forum seems to specialise in.

As I noted above, in my experience the UK MOT routinely fails brake disks for "visible rust".

This seems to be for purely cosmetic reasons, since the brakes pass the brake function test.

This means that cosmetics are important in a UK MOT context.

Rusty rims probably dont have much functional impact, though I have read somewhere that the rust can migrate inwards, undercutting the brake pad edges and reducing brake efficiency. I cant say I've ever noticed this, but if it was going to happen it'd be likely to happen here, under the sustained high pressure wash of the typhoon season. There was some slight bevelling of the pad edges which might have been due to this effect.

You don't feel that cleaning and lubricating the moving caliper parts and slides has any relevance to thier free movement and future corrosion resistance?

OK, then you don't. Black ain't black, and I don't want my baby back.

Edited by edlithgow on 25/08/2015 at 02:03

any disk brake equipped - Coke can for brake disks - RobJP

Again, that's not a substantive criticism, just an attempt at generalised put-down, which this forum seems to specialise in.

Interesting. I think every single person who has posted on this thread (apart from you) has said that they feel what you've done is a bodge, or words to the equivalent.

Yet you see fit to attack them all for their 'generalised put-down'.

It's not a generaliesd put-down, it's a few people saying "If you're going to do a job, do it properly. Don't bodge it"

What you've done is the equivalent of slapping some filler and paint on rusty sills to try to get a car through the MOT.

Oh, and speaking of which, you're worried about the rules on the UK MOT, and 'cosmetic looks' of brakes being a failure. Yet you keep on going on about 'typhoon season', meaning that you aren't in the UK. Which means that those failure points in the UK MOT aren't applicable to you.

Unless I'm missing something of vital importance in the weather forecasts

any disk brake equipped - Coke can for brake disks - edlithgow

The term "bodge" is itself a "generalised put down", at least the way its being used here.

A substantive criticism would actually specify what was wrong with the procedure, and this has not so far been done.

Analogies don't count, but your analogy is a poor one anyway. This is not the equivalent of filler to get through an MOT (not that I regard that as especially shocking), because as you yourself point out, I don't have to get through an MOT.

I have given a few reasons for doing it (and cleaning the calipers) which you have not plausibly addressed.

If I did have to get through an MOT, this disk treatment could not hide serious brake faults from a competent tester, but could only (perhaps) avoid a "cosmetic" failure, which I believe I have experienced in the past.

any disk brake equipped - Coke can for brake disks - bolt

The term "bodge" is itself a "generalised put down", at least the way its being used here.

A substantive criticism would actually specify what was wrong with the procedure, and this has not so far been done.

Analogies don't count, but your analogy is a poor one anyway. This is not the equivalent of filler to get through an MOT (not that I regard that as especially shocking), because as you yourself point out, I don't have to get through an MOT.

I have given a few reasons for doing it (and cleaning the calipers) which you have not plausibly addressed.

If I did have to get through an MOT, this disk treatment could not hide serious brake faults from a competent tester, but could only (perhaps) avoid a "cosmetic" failure, which I believe I have experienced in the past.

I really dont think you are interested in what anyone thinks, so its a bit of a wasted thread I think! ie there are people that need help, you dont

any disk brake equipped - Coke can for brake disks - John F

Again, that's not a substantive criticism, just an attempt at generalised put-down, which this forum seems to specialise in.

Interesting. I think every single person who has posted on this thread (apart from you) has said that they feel what you've done is a bodge, or words to the equivalent.

I didn't - see my post above. If cars were failed because of 'visible rust' on brake discs then virtually every car would fail!

It is useful to bang and grind off excess rust because if it gets too bad it will eventually stand proud of the disc and possibly make alarming grinding noises against adjacent structures which will sufficiently alarm the average punter into agreeing that they need to be (probably unnecessarily) replaced.

any disk brake equipped - Coke can for brake disks - bolt

I dont know what the pad looks like from your photo, but the chamfer on the disc may be under the outer section of the pad so the friction area will not be touching the disc

that means the pad will follow the chamfer and possibly break up( seen it before) also looks like the disc has been filed at some point in its life probably for the same reason you did what you did

any disk brake equipped - Coke can for brake disks - skidpan

As I noted above, in my experience the UK MOT routinely fails brake disks for "visible rust".

This seems to be for purely cosmetic reasons, since the brakes pass the brake function test.

This means that cosmetics are important in a UK MOT context.

I have been having cars MOT's in the UK since 1974 and have never yet had one fail on brakes. 7 year old cars always have quite a bit of "cosmetic" rust on the discs and calipers but that is not a reason to fail, providing they meet the efficiency required, the pistons move, they are securely fixed, not cracked with no fluid leaks or perished flexibles they will pass. There is no good reason to even note the rust as an advisory, even a year old car will have some present.

any disk brake equipped - Coke can for brake disks - edlithgow

As I noted above, in my experience the UK MOT routinely fails brake disks for "visible rust".

This seems to be for purely cosmetic reasons, since the brakes pass the brake function test.

This means that cosmetics are important in a UK MOT context.

I have been having cars MOT's in the UK since 1974 and have never yet had one fail on brakes. 7 year old cars always have quite a bit of "cosmetic" rust on the discs and calipers but that is not a reason to fail, providing they meet the efficiency required, the pistons move, they are securely fixed, not cracked with no fluid leaks or perished flexibles they will pass. There is no good reason to even note the rust as an advisory, even a year old car will have some present.

Agreed. That is logically what should happen, but it was not my experience, which is as stated.

I THINK "visible rust" was the actual phrase used on the fail sheet, but I might be remembering that wrong.

I'm not mis-remembering buying new disks (not cheap then for a Renault), to pass an MOT and then buying another pair to pass the next MOT.

I suppose I perhaps could have appealed these fails, and maybe should have, but it never seemed worth the trouble. I assume that, even if your appeal was upheld, you'd have to get re-tested there or somewhere else, and my feeling was they could always find something else to fail you on.

Of course, as someone rather unnecessarily observed above, the UK MOT isn't relevant to the car in those pictures, but its shaped my attitudes and is presumably relevant to the main audience of this forum.

Another reason for cleaning up the rims is that, unlike one of the posters above, I havn't had my eyeballs calibrated by the National Physical Laboratory and so I'll have to actually measure the disk thickness with a vernier caliper, when I can find it.

Unimpressive, but the best I can do. I assume rusty rims would cause an overestimate.

any disk brake equipped - Coke can for brake disks - edlithgow

I dont know what the pad looks like from your photo, but the chamfer on the disc may be under the outer section of the pad so the friction area will not be touching the disc

that means the pad will follow the chamfer and possibly break up( seen it before) also looks like the disc has been filed at some point in its life probably for the same reason you did what you did

Thanks for a specific comment.

Not sure I understand it though.

I've heard of people chamfering brake pads to stop squeal, and the edges of the holes in drilled disks have a chamfer. There does seem to be a chamfer on the edge of the rim (in other words it isn't a right-angle edge) but I don't see why/how that would cause the problem you describe.

It sounds as if you might mean the inner edge of the rim-corrosion band, but I'm not sure.

From memory, apart from being perhaps a bit undercut on the edges, the wear pattern on the pads looked fairly even. I don't think I photographed the pad surface after cleanup though, which was an oversight. If I have to take them off again I'll take a photo.

any disk brake equipped - Coke can for brake disks - edlithgow

Here's a commercial gizmo for cleaning up brake disks.

You can BUY it, so y'all might like it a bit better.

http://www.autosupplyco.com/content.wws?fname=braketruinstall.html

I tried a DIY version many years ago before a UK MOT, casting tile grouting onto the surface of old disc pads.

Didn't work much, since it wore away almost immediately, though some was retained in the central dust groove of the pads

any disk brake equipped - Coke can for brake disks - gordonbennet

Thats interesting stuff.

Years ago new Ferodo pads would come with a coating of what felt like grit bonded to the face of the friction material, they did a very good job of cleaning the face of the disc up, and were (still the case) some of the best brake pads i've ever used.

any disk brake equipped - Coke can for brake disks - Wackyracer

Thats interesting stuff.

Years ago new Ferodo pads would come with a coating of what felt like grit bonded to the face of the friction material, they did a very good job of cleaning the face of the disc up, and were (still the case) some of the best brake pads i've ever used.

I have got a set of those on the shelf in the garage.

When I bought EBC Greenstuff they had a similar coating of abrasive on them too but, the performance of them was not as good as I expected and they got replaced rather quickly for a new set of standard pads.

 

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