Custom Drilled brake rotors anyone

[storm 64]

Hi folks, I'm looking for ideas on hole patterns for brake rotors. Some kind of old school style. Any ideas would be great. Also, what diameter hole size would be good? Pictures and words of wisdom would be appreciated. 👍

Sharpy here is the sketch I couldn't private message to you.

[jabcb]

Seller smw70ss provides a rotor drilling service via eBay. Take a look at his listings for a few options.

[sharpy]

Just some pics but you want SLT files for ure machine dont you? Also found a disc here and the slots are a little wider. nothing a next size up a drill wont fix.

https://grabcad.com/library/1980-suzuki-gs1000-hole-pattern-on-a-earlier-front-disc-1

[mmattockx]

Also, what diameter hole size would be good?

One of the goals of drilling rotors is to increase the surface area for better cooling. For any hole size that is less than 2x the thickness of the rotor you get an increase in surface area. The smaller the hole, the greater the increase in area. That said, there are limits to how small you can go on the drill bit before it becomes fragile and hard to work with. I would use a bit size close to the rotor thickness (usually 5-6mm) for a decent area increase and a fairly robust drill bit. If you don't have experience drilling stainless you will find it is a pretty ignorant material to work with. You want a sharp bit, low speed, high feed pressure and coolant if possible.


Mark

[GregT]

Agree with Mark about working stainless. It's not fun.

Whatever hole pattern you use, it should cover the complete pad area. Discs with a pattern which leaves strips undrilled inevitably wear with ridges.
Once they're ridged, they're past recovery.

[storm 64]

I think I decided on a bolt hole pattern. Four rows of 16 .3125dia. holes spaced on 5° increments. I think it will complement my new wheels very nice.👍

[jabcb]

Have you considered an alternating pattern? You can use fewer holes and still have them overlap.


For example, I had some GT750 rotors drilled with a 3-2 pattern for a total of 45 holes.
GT750_DrilledRotor_0508.jpg

[sharpy]

Just like Jabcb says, you need alternating pattern so some serious groove dont develop. Below is ure pic and better set up......

[storm 64]

I drilled my brake rotors today. It drilled like a hot knife going through butter! Gotta love modern tooling. I went with 48 .3125 dia. holes. I was thinking doing 64 holes. I'm happy the way they came out.

[storm 64]

And after I painted them. I was contemplating on painting them black or silver... I went with silver👍