Do Any Aftermarket Rotors have Cast Holes?
#11
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Holes are holes. The "cast holes are different than drilled holes" thing is a myth. Holes don't cause cracks because they have been drilled; they cause cracks because they are stress concentrators. It's a matter of geometry and metal properties, not manufacturing technique.
Even the cast holes get finish-machined anyway.
Now I'm not saying a poor manufacturing process can't make things worse, because it can. Improperly drilled holes can be worse than carefully drilled holes.
Even the cast holes get finish-machined anyway.
Now I'm not saying a poor manufacturing process can't make things worse, because it can. Improperly drilled holes can be worse than carefully drilled holes.
#13
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Originally Posted by mikegarrison,Jul 28 2006, 03:14 PM
Holes are holes. The "cast holes are different than drilled holes" thing is a myth. Holes don't cause cracks because they have been drilled; they cause cracks because they are stress concentrators. It's a matter of geometry and metal properties, not manufacturing technique.
Even the cast holes get finish-machined anyway.
Now I'm not saying a poor manufacturing process can't make things worse, because it can. Improperly drilled holes can be worse than carefully drilled holes.
Even the cast holes get finish-machined anyway.
Now I'm not saying a poor manufacturing process can't make things worse, because it can. Improperly drilled holes can be worse than carefully drilled holes.
All that being said, the drilled ones just look bad-ass. I saw a Lambo today at the Home Depot w/ big drilled rotors and it looked awesome. Also saw a new M5 earlier in the week w/ similar rotors...again, awesome.
#14
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Originally Posted by dmw16,Jul 28 2006, 09:04 PM
This is not a true statement at all. Drilling a cast part interupts the internal structure of the material. It also creates residual stress from the machining process. No matter how the holes are created they still can create stress concentrations, but a cast hole is stronger than a drilled hole.
We aren't talking about single-crystal exotic metal turbine blades here, we're talking about a mass-produced cast iron brake rotor.
Residual stresses can be removed by heat treating.
#15
Originally Posted by SpitfireS,Jul 28 2006, 06:56 PM
Holes = a place for the hot gas coming out of your pads and or brake dust to go = more friction =
But I admit, I bought the Spoon rotors for bling only.
And they look
But I admit, I bought the Spoon rotors for bling only.
And they look
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Originally Posted by Jasonoff,Jul 29 2006, 06:19 AM
Sure if your pads were made in the 60's or 70's
Ohh well.. but they look
Allthough on the Stoptech website they do mention slotted / drilled rotors have some benefits, mainly to provide a place for "debris" to go.
Brake dust isnt something from the past, I mean, I only have to look at my wheels.
They also mention drilled rotors are more likely to crack during track conditions.
And Stoptech also makes plain rotors.
I'm not trying to prove my point.
Not at all.
Because I know I have no point to prove.
But..
They look
#17
Originally Posted by SpitfireS,Jul 29 2006, 07:17 AM
Ohh well.. but they look
Allthough on the Stoptech website they do mention slotted / drilled rotors have some benefits, mainly to provide a place for "debris" to go.
Brake dust isnt something from the past, I mean, I only have to look at my wheels.
They also mention drilled rotors are more likely to crack during track conditions.
And Stoptech also makes plain rotors.
I'm not trying to prove my point.
Not at all.
Because I know I have no point to prove.
But..
They look
#18
I chose to go a different route. I picked up some slotted and cadmium plated rotors from Centric (thanx Spugen) almost 2 years ago. I like this brand in particular because the slots do not go all the way to the edges, like the Power Slots for instance. That is another place where cross-drilled and slotted rotors can crack, since there is less material there. The cadmium plating keeps the rust away pretty well, except for the pad contact areas ofcourse but that gets swept away after a couple touches of the brake pedal. The plating doesn't last forever and you'll get some rust in the venting (fronts) and the hat (center).
-Hockey
-Hockey
#19
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Originally Posted by dmw16,Jul 28 2006, 08:04 PM
This is not a true statement at all. Drilling a cast part interupts the internal structure of the material. It also creates residual stress from the machining process. No matter how the holes are created they still can create stress concentrations, but a cast hole is stronger than a drilled hole.
All that being said, the drilled ones just look bad-ass. I saw a Lambo today at the Home Depot w/ big drilled rotors and it looked awesome. Also saw a new M5 earlier in the week w/ similar rotors...again, awesome.
All that being said, the drilled ones just look bad-ass. I saw a Lambo today at the Home Depot w/ big drilled rotors and it looked awesome. Also saw a new M5 earlier in the week w/ similar rotors...again, awesome.
#20
Originally Posted by SpitfireS,Jul 29 2006, 08:17 AM
Ohh well.. but they look
Allthough on the Stoptech website they do mention slotted / drilled rotors have some benefits, mainly to provide a place for "debris" to go.
Brake dust isnt something from the past, I mean, I only have to look at my wheels.
They also mention drilled rotors are more likely to crack during track conditions.
And Stoptech also makes plain rotors.
I'm not trying to prove my point.
Not at all.
Because I know I have no point to prove.
But..
They look
Slots "can" help prevent glazing "if" the edges are sharp but it's not necessary.
As for evac of brake dust. If you figure a 215/45-17 tire revs at aprox 820rev/mile @ 60mph that's 820rpm or around 13-14rev per sec. At that speed I'd be checking the inside of your rims or fender liner for the dust