I've heard slotted rotors are made by putting slots in standard rotors. If this is true then it should be possible to add slots to existing rotors no? Anyone know much more about this?

i wonder if thats safe lol:nuts: who knows!

i wonder if thats safe lol:nuts: who knows!
That's what i'm trying to find out. As far as i know slotted rotors are just standard rotors that have had the slots machined into their surface. Pretty sure they aren't cast that way?

That's what i'm trying to find out. As far as i know slotted rotors are just standard rotors that have had the slots machined into their surface. Pretty sure they aren't cast that way?

*gets grinder out to see*

If I were you I would just buy some. Doing them yourself could turn out dangerous, or it could just look crap. If you can see the disks through the rims, everybody is going to know you cut them yourself and it will look so dodge...
Thats my 2c..

mayb get some spare ones and give it a shot? im not sure though the breaks are a pretty important bit. im betting there is some sort of formula about slot width depth and spacing and direction. i kno theyre slotted to cool it down (i think...) same reason as the drilled but my confidence isnt high on testing them lol mayb ask a mech or wheel/break tech?

lol I'm not going to do this myself. Don't have the tools or experience. Just finding out if it's even possible.

lol well keep us posted im interested! Just to find out if its possibe!

its a tad ghetto. i hope you dont mean slotting your current rotors... cos they get worn away slightly each time you brake.

IF that's what they do when the manufacture slotted rotors, and it was done professionally, then I don't see why it wouldn't work.
Not a bad idea but I'd ask a couple of brake experts first.

That's what i'm trying to find out. As far as i know slotted rotors are just standard rotors that have had the slots machined into their surface. Pretty sure they aren't cast that way?

Remembering how mine looked when I first got them - the slots were definitely machined into the surface - not cast. So yes - if you had access to the right machinery it should theoretically be possible to "slot" standard rotors.

You would have to of course ensure the amount you machine out is such that it doesn't weaken the rotors by making them too thin - which to me means it's a job better left to professionals.

brake----cars have them..

break---what the !!!!

Yeh just sent an email about it to Peter Koning from Hoppers Stoppers
Let's see what he says

Was going to suggest annoying Peter! He luvs us ;)

I was wanting to know it I could machine some dimples into the surface of the rotor (as apposed to drilling completely thru the rotor and becoming a cross-drilled item). Wondering if the machining needs to be done prior to the rotor being heated under normal use or if stress areas can develope?

Was going to suggest annoying Peter! He luvs us ;)

I was wanting to know it I could machine some dimples into the surface of the rotor (as apposed to drilling completely thru the rotor and becoming a cross-drilled item). Wondering if the machining needs to be done prior to the rotor being heated under normal use or if stress areas can develope?

Wouldnt that mean that the dimples would get brake dust all in them? I thought the slotted were also to let more of the dust escape...

its not so much for the dust - its to prevent outgassing, disperse heat and continuously deglaze the pad.

And it know its not a huge help but I stumbled across this http://www.performanceforums.com/forums/showthread.php?t=67133748

Go to a CNC machining shop, My uncle gets custom slots put into his rotor's when he does brake conversions on old stang's and the like.
Mohit the place he gets them done at is actually literally around the corner from ART, dunno what the name is though

;1052638']

Go to a CNC machining shop, My uncle gets custom slots put into his rotor's when he does brake conversions on old stang's and the like.
Mohit the place he gets them done at is actually literally around the corner from ART, dunno what the name is though
Yeh i think i know the place you're mentioning it's right at the start of Kolora Rd

EDIT: The place is called Pro Heads (http://www.proheads.com.au) lol

Just got this reply back from Peter Koning of Hoppers Stoppers:

"Yes slotted rotors are just slots cut on standard rotors.
However it takes a proper rotating cutter tool in the milling machine so not everyone has the equipment to do it."

So the right shop with the right equipment should be able to do this.

Just got this reply back from Peter Koning of Hoppers Stoppers:

"Yes slotted rotors are just slots cut on standard rotors.
However it takes a proper rotating cutter tool in the milling machine so not everyone has the equipment to do it."

So the right shop with the right equipment should be able to do this.

did he give you a price? or was he just mentioning that some workshops can do the job, but not his?

it'd be pretty cool if it was a more cost-effective brake upgrade than getting entirely new rotors

did he give you a price? or was he just mentioning that some workshops can do the job, but not his?

it'd be pretty cool if it was a more cost-effective brake upgrade than getting entirely new rotors
He doesn't do them. Best thing would be to find a machining shop near you who would do it.

did he give you a price? or was he just mentioning that some workshops can do the job, but not his?

it'd be pretty cool if it was a more cost-effective brake upgrade than getting entirely new rotors

Cant see this being very cost effective.

If it costs anything more than $50 a rotor to slot, its not worth it. As rotors do wear out over time, your rotors might only be at 50%.

Slotted rotors are what? $150 a piece?

I guess it comes down to how much it costs.

how long will slotted rotors last? spose it depends on how much life you'll get from your existing rotors compared to new slotted ones

EDIT: like if new slotted rotor costs $150, and to slot existing rotors costs $75, then if you're existing rotors were to last longer than half the time of the new ones you'd be in the black :D

@EzyBoy (and others).... When I was ordering slotted rotors for my Tj and KJ from GSL Rallysport in Brisbane, they mentioned a couple of things. They seemed to prefer RDA rotors over DBA, and think it was a performance/quality/reliability issue.

GSL also definitely suggested slotteds for me as opposed to cross-drilled - reason being that even with street use the cross-drilled ones sometimes develop little stress cracks, and as I am not a high-stakes driver or occasional racer I wouldn't even need the cross-drilling. RDA have a range of "gold-passivated" rotors I was interested in (goldish colour to the rotor and doesn't rust, or not as much) - GSL guys weren't that impressed, just said get the basic DBA slotteds - commonsense advice, not looking to extract more money from me.

The "secret weapon" in my changed brakes is, I suspect, the pads: QFM (Queensland Friction Materials) pads, the "HPX" compound - have only put the fronts in so far (gonna wear out the rears before i change them). I'm very happy and more confident that I have effective brakes now. Was considering upgrading calipers etc from TJ/KJ standard, but with the slotteds and HPX pads I'm happy now.

EDIT: I reckon you'd be up for a fair bit of set-up cost to have a set of rotors machined...... you'd have to take fairly precise amounts of material out of rotors all the way around the rotor, to allow wheel balancing to be achieved.
I suspect that after-market slotteds have a slight chamfer on the lip of the slot, to be less-aggressive on the pad material.
A workshop may prefer to machine a new rotor than a used one, in case 'hot-spots' etc have occurred during the previous use of the rotors, which may then introduce further stresses/weaknesses with the machining and subsequent use.
That's just my 2c - I'd run literally miles if I knew a "home made" set of slotted was anywhere near me on the roads!! Think it sounds like a recipe for disaster to me.

Just adding my 2c worth. I was told by a mechanic, correct me if I'm wrong, that there is a minimum weight requirement for rotors, not just thickness. I presume this means that the slotted rotors are made heavier than normal rotors so that minum weight is maintained as rotors wear.

On the topic of DBA slotted rotors. I had a pair on the front of my old KS fitted with lucas pads. They did not last long at all, in fact, by the time the pads required chaning (which was about 20000kms from memory), the rotors were already below minimum thickness. I wrote an email of complaint to DBA and they offered a free set for the next time I needed a pair. Mind you, the DBA slotted rotors together with lucas pads really bite.

As someone mentioned before it comes down to the cost of getting standard rotors machine slotted. I won't be doing this as my friend's friend works at RDA and can get me really cheap slotted rotors.

And yes QFM pads are the shiz. Used them on both my previous cars (Verada and RAV4) and will use them on my current car as well when the time comes.

. . . . . my friend's friend works at RDA and can get me really cheap slotted rotors.
.

Ah Mohit, everyone's new best mate (or those who want better brakes) Lulz!!

EDIT: Never been to a modded-car show etc, but just had a thought, does anyone machine brake rotors purely for "looks" on show cars? Either just cool-looking patterns, or logo's etc? This could be a step-up in the Rice-Factor stakes!! I've noticed mainstream Motor Show cars with custom-cut tyre treads on concept vehicles etc.....

As someone mentioned before it comes down to the cost of getting standard rotors machine slotted. I won't be doing this as my friend's friend works at RDA and can get me really cheap slotted rotors.

And yes QFM pads are the shiz. Used them on both my previous cars (Verada and RAV4) and will use them on my current car as well when the time comes.

Hmm, I see a group buy coming along. I'll need new pads and rotors soon (next month). The rotor and pads are still the ones from factory and the car has done 72000kms.

Slotted rotors are what? $150 a piece?

I had a basic set of RDA slotted rotors installed a fortnight ago on my standard single piston brakes, and they were only $110 a piece. By the time you machined and slotted your existing rotors, I doubt it'd be worth it, considering there's already an off-the-shelf equivalent.

Pretty cool to know that you can do it though.

EDIT: Never been to a modded-car show etc, but just had a thought, does anyone machine brake rotors purely for "looks" on show cars? Either just cool-looking patterns, or logo's etc? This could be a step-up in the Rice-Factor stakes!! I've noticed mainstream Motor Show cars with custom-cut tyre treads on concept vehicles etc.....

Yup its been done before.

By Osman Bros, on their green wrx from back in the day - cant find good pics of it, or any for that matter.

Shame - but hey it has been done.

Hahaha will check with my mate's mate and see if a brake group buy can be done.

BTW i had mentiond Pro Heads a couple of pages ago who do machining stuff. Sent them an email yesterday and just got this reply:

"Hi,

That’s not really what we do. We actually use Harrop Engineering for our brake machining. They will be able to help you. www.harrop.com.au

We could do it on hourly rate, I would think it would be around the $400 mark for four disks.
But I would suggest it would be cheaper to buy new disks already slotted.

Regards
Scott March
ProHeads"

So there you go better to buy slotted rotors from the get go.

Yeah couldnt see it being cheaper than roughly $100 a rotor, considering basic machining is around $40-60 for the front pair.

Harrop engineering - pwoah....nice!

I reckon these home made slotted rotors would look just dandy with a set of those clip on Brembo caliper covers... Very tasteful.