Disk rotor material?

Nick said:

Dear All,

Does anyone know what grade of stainless steel is typically used for
bicycle disk brake rotors?

Thanks for your help.

why?

"jim beam" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Nick said:

Dear All,

Does anyone know what grade of stainless steel is typically used for
bicycle disk brake rotors?

Thanks for your help.

why?

Why not, idiot?

jim beam said:

Nick said:

Dear All,

Does anyone know what grade of stainless steel is typically used for
bicycle disk brake rotors?

Thanks for your help.

why?

"jim beam" is actually Prisoner No. 6.

--
Tom Sherman - Holstein-Friesland Bovinia
Beer - It's not just for breakfast anymore!

"Tom Sherman" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

jim beam said:

Nick said:

Dear All,

Does anyone know what grade of stainless steel is typically used for
bicycle disk brake rotors?

Thanks for your help.

why?

"jim beam" is actually Prisoner No. 6.

That would explain his "classified materials lecture over 30 years ago" on
non-existent "sikorski" helo composite rotors...

Hello all,

We have a laser cutter at work and I work as a designer so was
thinking of designing my own rotors.

I have tried looking on the internet to see if I could find out the
material used without success.

I *think* we use 316 grade in various thicknesses but am unsure if
this will be suitable.

Perhaps it doesn't really matter!

Thanks,

Nick

Nick said:

Hello all,

We have a laser cutter at work and I work as a designer so was
thinking of designing my own rotors.

I have tried looking on the internet to see if I could find out the
material used without success.

I *think* we use 316 grade in various thicknesses but am unsure if
this will be suitable.

Perhaps it doesn't really matter!

Thanks,

Nick

T316 or T304/304L will be fine if you're just looking for something
cheap to screw around with, but it's not going to wear too well. Full
hard T301 would be ideal, but it's very expensive.

Nick said:

Hello all,

We have a laser cutter at work and I work as a designer so was
thinking of designing my own rotors.

I have tried looking on the internet to see if I could find out the
material used without success.

I *think* we use 316 grade in various thicknesses but am unsure if
this will be suitable.

Perhaps it doesn't really matter!

Thanks,

Nick

it will matter. too hard, and you'll lose braking efficiency. too
soft, it won't last. it also needs to not gall.

unfortunately, i don't know what grade the material is, but if you have
an old disk, give it to your material supplier, and say you want more of
the same. they should be able to provide.

two more things:

1. when you're done, you need to make sure the friction surfaces are
parallel - if they're not, you're going to get some really grabby brakes.

2. be very aware of fatigue when designing. you'll notice that all
existing designs avoid sharp angles in their layout, and have spiders
where the load arms work in compression, not tension when braking. this
is all to mitigate fatigue - emulate these principles!

That's very helpful, thanks guys!

I may well just copy existing designs but add little personal touches.

Cheers,

Nick

"jim beam" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

it will matter. too hard, and you'll lose braking efficiency. too soft,
it won't last. it also needs to not gall.

Excellent. Stainless steel can be too soft. Idiot.

Quoted message said:

unfortunately, i don't know what grade the material is, but if you have an
old disk, give it to your material supplier, and say you want more of the
same. they should be able to provide.

Duh.

Quoted message said:

two more things:

1. when you're done, you need to make sure the friction surfaces are
parallel - if they're not, you're going to get some really grabby brakes.

Really? Master of the bleeding obvious, aren't we?

Quoted message said:

2. be very aware of fatigue when designing. you'll notice that all
existing designs avoid sharp angles in their layout, and have spiders
where the load arms work in compression, not tension when braking. this
is all to mitigate fatigue - emulate these principles!

Really beamboy, your [censored] keeps astounding. Where do you come up with
these?

"Nick" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Hello all,

We have a laser cutter at work and I work as a designer so was
thinking of designing my own rotors.

I have tried looking on the internet to see if I could find out the
material used without success.

I *think* we use 316 grade in various thicknesses but am unsure if
this will be suitable.

Perhaps it doesn't really matter!

Thanks,

Nick

I don't know what kind of metal is used in bicycle disc brake rotors.

About 46RC is the maximum hardness for 300 series stainless steels like
303, 304 and 316 (18/8 Inox). They can only be hardened by cold working
processes such as cold rolling, drawing or bending operations. At 46RC
these metals are not going to have a lot of abrasion resistance.

For an experiment thin sheet metal made from any of the 300 series
stainless steels will probably work fine. Thin sheet made of these metals
is usually in the mid to high 30s on the Rockwell C scale.

Some of the 400 series stainless steels can be hardened by heat treatment
to the mid 50s on the Rockwell hardness scale. A common hand file has a
Rockwell hardness of around 57-62RC.

440C Stainless can be hardened up to 67RC. This is the stainless used for
knives and other cutlery.

There are specialty abrasion resistant steels and other metals that also
have corrosion resistant properties but they will be hard to find in the
thickness required for bike brake rotors.

Chas.