Slotted Rotors, Where The Hell Are They

[daniel3507]

Im looking at Stoptech rotors and don't really want drilled because Ive heard that they warp easier and cant be turned. I cant seem to find any rotors that are just slotted though. they all seem to be drilled and slotted. Ive found them for newer rangers but not mine. Do they even make a slotted rotor for a 93?

 

[ragajungle]

baer brakes maybe?

 

[daniel3507]

Finally found some from R1 Concepts. After reading some reviews I think they will work great with my new pads. Im even thinking about getting the powder coated drums they have

 

[Nater]

I think I saw some on Summit...Don't know the brand off the top of my head

 

[Boggin]

i got a question,, whats the point of slotted and drilled rotors? do they make your truck anymore lightweight to make her go faster? haha jk but seriously i always wondered that
[/threadjack]

 

[daniel3507]

The ones on summit that i was seeing were all drilled and slotted. I was able to find slotted rotors no problem for 98 and up but nothing older till i found r1 concepts.

from my understanding, slotted rotors help clean off the pad and help in cooling. cross drilled helps prevent gas build up between the rotors and pads under heavy braking.

 

[michowski]

I got drilled and slotted for my 93 ranger with pads for like 120 shipped a few years back. No warpage and no issues yet. Not sure if they can be cut down and I doubt they can but I plan to just lightly with some emory cloth clean the surface when I change pads. I also did some searched and can find drilled only, or drilled and slotted. Not just slotted.

 

[daniel3507]

If anyone is interested in slotted only rotors for a ranger older than 98 look at r1concepts.
http://www.r1concepts.com/
only place i was able to find that has a good quality rotor that is slotted only. im pretty excited to get them

 

[AllanD]

i got a question,, whats the point of slotted and drilled rotors? do they make your truck anymore lightweight to make her go faster? haha jk but seriously i always wondered that
[/threadjack]

the point is that once the brake pads reach a certain temperature the pads start "outgassing" as the binder material decomposes... this gas cause the brake pads to "float" in this layer of hot vapor and braking effectiveness disappears.

This is called "compound fade" and is usually exibited to the driver as the brake pedal getting hard as hell to push and the vehicle won't stop.

Braking effectiveness returns when things are allowed to cool down.

Drilled rotors or slotted rotors allow the hot gasses to escape.

that being said drilled rotors don't warp because they are drilled.
drilled rotors warp because they are usually rediculously cheap cast iron rotors made in China (Peoples Repulbic of) and that means they are essentially shit before they got near the drill bit.

What drilled rotors DO do is to crack, radial cracks propagating from the drilled holes. because every hole is in essence a stress concentration and this on a piece of relatively brittle iron that is being temperature cycled from ambient to as much as 850'F.

Slotting rotors is 99% as effective as drilled rotors in allowing gas to escape but most machinists will refuse to cut them because of the same problem with the drilled rotors...

the fact that a cutting tool cutting smoothly isn't a problem, but one that encounters a void (the slot or hole) experiences a hell of a shock when it starts cutting again. And since the cutting tools are essentially hard ceramic materials this can ruin them, unless the machinist takes the tedious approach and cuts off a very small ammount of material in each of multiple passes
(time consuming)

IF you provide your own cutting bits, most brake lathes use the six-way
triangular cutting bits AND you pay them for their time you can usually talk a dedicated machinist into cutting them...


No not the guy at the big chain auto parts store, but the guy at the old school auto parts that actually does engine machining on-site will do them for you....

Hey my machinist actually has a crankshaft grinder, his cylinder head mill is the size of a hot tub built for four (it was originally made to mill heads on inline aircraft engines!)

He'll willingly do anything you can think of... but you might not like the price if it's something complicated and time consuming.

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