Has anyone turned brake rotors?

[vsustko]

Thank you everyone, glad that we have the tools for this. While it may be advised to bring to a shop, this is makerspace and I will plan to skim off the surfaces muself. Will test on an older disc first.

We have a Miata which we run in WRL and Champ series. Vented Brembo rotors with high quality PFC brake pads. Calipers are rebuilt every 30 hours.

[ESmith]

@Adam_Oas

The vast majority of the stance crowd that just slaps a set of cheap drilled disks on their car and pairs them with whatever craptacular pads is very likely decreasing the actual performance of their vehicle from my limited research and knowledge.

From what I’ve seen, the stance crowd does the same thing as the cool kids with their messenger bags a couple decades ago - adopting a mutated/bastardized/derivative form of something utilitarian with the very wrong assumption that the function will follow. Seen enough slammed-to-the-ground Integras (yes, some of those are show cars with airbags; I have however seen countless instances of such nonsense rolling on the street as pictured) with telltale bizarre wear patterns on the inside tread on their tires to know that performance losses are assured when pursuing a look over actual reality-based utility.

Believe it or not, kids, the engineers that tuned the suspension on your bone-stock '02 Civic probably knew a hell of a lot more about how to make it perform on a track than the dude that sold you your hella cool cut springs. If only someone made conical tires to better manage the hilarious negative camber so popular with that crowd.

[Adam_Oas]

@ESmith

engineers that tuned the suspension on your bone-stock '02 Civic

Probably technically correct that they know a lot more about track suspension, but honestly a 02 civic wasn’t engineered for the track. The theory is sound, lower COG, adding camber etc are all generically good things, but randomly throwing parts at a hope of beneficial changes are often wasted.

[kbraby]

@zmetzing

I’ve wondered if the Bridgeport and a fly cutter might be the best way to resurface rotors. You’d mount the rotor on the rotary table, offset to the side so that the fly cutter would make somewhat-perpendicular arcs across the rotor, rather than making a bunch of concentric grooves. Ideally, you’d have the rotary table motorized at a constant rate.

I’ve seen this exact method suggested, and used by someone submitting to a hobbyist magazine. I suspect the key item is to try to get the two planes as parallel as possible and as perpindicular to the axle as possible. Maybe lightly lap the hat top, do that side first, indicating against the top of the hat through a turn, do the fly cut, flip, and indicate against the bottom face?

[ESmith]

@Adam_Oas

Probably technically correct that they know a lot more about track suspension, but honestly a 02 civic wasn’t engineered for the track.

Therein lies the fundamental rub. Most vehicles are designed with long lifetimes of commuting and highway driving in mind. The suspension exists to keep the wheels on the road under these conditions and improve ride comfort.

@Adam_Oas

The theory is sound, lower COG, adding camber etc are all generically good things, but randomly throwing parts at a hope of beneficial changes are often wasted.

I’m going to speculate that our example '02 Civic in healthy stock form outperforms the typical stance config where “performance” metrics are inches of lowering, conspicuous degrees of camber, cost, color of the parts (added bonus for red paint/anodizing), and reseller profitability with the resultant greater promotion/influencer placement on periodicals/websites/facebook groups.

Take considered aspects of what you’ve mentioned and you one can almost certainly tune an '02 Civic to perform markedly better than stock on the track. But it probably won’t sport the look that the stance crowd prefers.

[Ferman]

@Adam_Oas

honestly a 02 civic wasn’t engineered for the track.

87-2000s were much better at it.

Speaking of track.

https://www.facebook.com/devilracersDR/videos/2112314758996775/

[Adam_Oas]

@Ferman

87-2000s

Yep, in 01 they put the macphersons on and turned a fun little car into a true econobox.

[Photomancer]

I know “cryoing” on cutting tools is done as a last operation. No direct experience with other than cryo cutters. We found the cost vs life wasn’t sufficient to justify on what we were milling. May work wonders on other things. Of course it still bothers me to cut steel, Ti, etc. with ceramic cutters (of course my visual is a chunk of a broken dinner plate, even though I know it’s not even remotely the same - they take tremendous heat)

[Adam_Oas]

Thinking about it a little more logically, the heat of cutting is probably less than the heat generated after standing on the stop pedal after a bunch of long straights during a hot lap session.

The reports that I hear from the track guys that I talk to are that for the car that I drive (S2000) that the increased cost doesn’t justify the extra life. Obviously YMMV, literally.

[Photomancer]

I think one reason a lot of rotors are made out of cast material is they hold up better to thermal cycling and are less susceptible to the oxidation burn out that steel has. A quick Google finds:

I would imagine various combinations of rotors pads, geometry of each all create different results as well as driver heavy-footedness. I’m sure F1 would make rotors out of Platinum with diaomnd dust composite pads if it gave them some perceived edge.

My RAV4 (RIP) was getting 60K-70K on a set of standard brakes … but 95% of my driving was was on freeways so brakes hardly used.