Pads glazing?

[lapsio]

So I recently changed my stock PP pads and disks to DBA Xtreme Performance kit and... They're quite sh*t. I keep glazing them all the time. At first I thought that maybe I'm doing something wrong but then it kinda struck me...

How the hell those guys don't have problems with glazed pads yet I do:


And yeah sure I kinda know the answer why, they probably didn't pay 1k for those breaks but my question is rather - where's the level at which you don't really need to worry about pads glazing so much? Or is it maybe just normal for race cars breaks to glaze and they only rely on adhesive friction or something like that?

I'm aware that you can kill any breaks if you want to but the thing is I'm not doing anything really offensive like riding breaks accidentally or breaking on throttle or anything like that. Sure, I'm not exactly easy on them and I do perform a lot of high speed breaking but it's FAR from what I do to my track day MX5 NB which doesn't suffer from such issue... I also obviously didn't have any issues with OE PP Brembo set...

Is there some specific condition that makes pads glaze other than just thermals? I think the'yre bedded quite fine by now, I used to have issues with really uneven pad film coverage but now it kinda seems fine to me I guess...

[CSG Mike]

stock PP pads are for street use.

You need race pads for race or race type (e.g. canyon runs) use, if you're carrying any sort of speed.

Your photo indicates that you need some more pad for what you're doing.

Your NB is a far lighter, lower power car. KE = (0.5)MV²

[lapsio]

Originally Posted by CSG Mike

stock PP pads are for street use.

You need race pads for race or race type (e.g. canyon runs) use, if you're carrying any sort of speed.

Your photo indicates that you need some more pad for what you're doing.

Your NB is a far lighter, lower power car. KE = (0.5)MV²

I thought DBA Xtreme Performance pads are already track-ready but it seems that no so much... welp :T I guess I'll have to get race performance then.

[cmiovino]

Did you bed the pads in properly? That's step one.

[lapsio]

Originally Posted by cmiovino

Did you bed the pads in properly? That's step one.

I tried. I mean they were really tough to break in. At first for really long time I was having something like this:



Then I glazed them and had them resurfaced with sandpaper, driven some more (at this point they have like 2k km on them) and now it looks more like this:




But please note these were not 2k km of slow, old man driving. More like mixed use with starting 300km of old man driving and some rainy days. I'm not entirely sure if they're "properly bedded". People say "just drive 300km" but for sure it wasn't the case here and 300 km were not even remotely close to being enough. I performed a lot of those track-brakes fast bedding procedures with multiple 100-20 cycles, then cooldown, then few cycles again and even few extended cycles that are typically recommended for sport pads (140-40). I spent a lot of time, effort and fuel trying to get them to work and at this point I'm a bit frustrated with their behavior. I no longer resurface them with sandpaper considering that after glazing they get back to normal after some time of slow driving. Still it's frustrating.

Nonetheless pad film is relatively even now and doesn't form distinctive ring like it used to, so I believe that means they're bedded properly? I guess?...

[cmiovino]

Originally Posted by lapsio

I believe that means they're bedded properly? I guess?...

I can tell you what I do and it's worked every time I've bedded pads for all my cars and anyone I do a brake change for.

Once everything is installed as soon as reasonable possible, I head out to this mostly unused tollway. Get the car up to ~70mph, moderate braking down to about 25-30. Do this a few times to get some heat in the brakes. You want to gradually get them up to a hotter temperate.

Then the fun begins. Mostly heavy stop from 70 down to about 15-20. Don't come to a complete stop. Don't engage the ABS. You want to be at about 80-90% of a full panic stop. Do this about 4-6 times as traffic allows. Obviously I'm being hyper aware of any traffic around me or cops. I let others pass before slamming on my brakes, obviously. Usually there's near no one using this road.

Then continue driving about 20 miles to completely cool down the brakes without using them at all if possible. Hit my exit and come on back.

Basically you'll find some form of this break in for most manufactures. You're getting the pads seated on the rotors, getting things up to temp and even pretty hot, but not like "track day" hot. Then letting the air cool them before coming to a complete stop.

Any car I've done this one the brakes just work like magic afterwards. You get a layer of pad material on the disc, so rotor wear is kept in check and you have a good pad on pad mating surface.

You basically need to do this with any sport or track pad. I'd even say you really need to do it with any pads, even OEM and basic replacements.

[fredzy]

Originally Posted by cmiovino

Any car I've done this one the brakes just work like magic afterwards. You get a layer of pad material on the disc, so rotor wear is kept in check and you have a good pad on pad mating surface.

You basically need to do this with any sport or track pad. I'd even say you really need to do it with any pads, even OEM and basic replacements.

I agree with bed-in being a good thing, but mostly only right before heading to the track, and only if the type of pad benefits from it.

Mild street pads (I think ceramic especially) often don't benefit from it at all and it can be a detriment. Carbotech 1521 for example they say don't do it, just drive normal for first 200-300 miles. I recently made the mistake of driving a little too hard on a new set of them and got some serious pad squeal. I had maybe 20 normal miles on them then went for a spirited drive, only 4-5 hard braking in span of less than 10 mins of driving was enough to glaze them. Rather than take everything apart and sanding I'm just letting them wear back down to a good state with exclusively normal/easy braking. The squeal is already mostly gone after an additional 75 miles. Once they quiet down I'll make sure to put another 200mi on them avoiding getting much heat into them before I let er rip. I think the idea is you need to burn out the resin at the contact surface slowly before going for high heat. Otherwise you get the glazing effect. I wonder if this is what's happening to @lapsio. Need to run them longer avoiding heat before giving it the gusto, and don't do any bedding-in. DBA should have specific instructions for that compound either way.

My other issue with this transfer-layer forming procedure is how temporary it is if the car is driven normal on street. I found this thread looking for how other people have dealt with maintaining the layer. I think it only makes sense to do the transfer layer burnishing right before a track day. After that it will wear off quickly with normal driving (that's my experience, anyhow) so leave it that way until the next track day, or use a street pad and don't do it at all if you don't go to the track.

[lapsio]

Originally Posted by fredzy

My other issue with this transfer-layer forming procedure is how temporary it is if the car is driven normal on street. I found this thread looking for how other people have dealt with maintaining the layer. I think it only makes sense to do the transfer layer burnishing right before a track day. After that it will wear off quickly with normal driving (that's my experience, anyhow) so leave it that way until the next track day, or use a street pad and don't do it at all if you don't go to the track.

I noticed that as well but luckily I'm daily driving like an absolute idiot so I have no trouble with regenerating transfer layer during daily driving. That said I always have to remember that it gets wiped after any rainy day since during those I'm unable to break hard enough to get them to optimal temps since tires don't have enough grip on wet surface. Whenever I forget about that I tend to get myself into very dodgy situations...

[gen3v8]

I run DBA XP pads. They need a bed in ,of some sort ,every track day.

[lapsio]

So I consulted DBA support, sent them recent photos of my discs (since my problem with brakes fade was still very much apparent) and they basically told me that hoho, sucks to be me but it that doesn't really seem to be proper pad film on those discs, more like decaying corpse of severely overheated pads...




It also turns out that DBA RP pads are not offered in Europe unfortunately. However mad respects to DBA support because instead of making up some bullsh*t to sell me more of their products, they actually plain recommended me DS2500 or DS3000 pads. So I guess I'll just try those instead c:

[strat61caster]

USA track 86’s typically use DS1.11, ds2500 are more Street/autox/autoslalom oriented and will overheat/glaze with track usage. They will survive but I wouldn’t bother buying them for track usage.

[Clipdat]

He's not tracking, he's just driving like an obnoxious twat in public.