Rotor minimum thickness

[IvaTiger]

Does anyone know what to the minimum rotor thickness is for the standard hub that came with the car

 

[Warren]

I have asked the same question in person to several guys and usually I get the....
Well when it doesn't stop the car anymore then you need to get some new ones.
I think the rule of thumb is about a half an inch. That's all I've been able to pull from the guy's.

 

[IvaTiger]

Lol
Sounds right !

 

[Hoghead]

From my very bad memory, is 1/2" not the new thickness?

A quick google search turned up:
The new rotors are .500 inch and the minimum is .375 inch. The data came
from a factory service bulletin. Hope this helps.

I just bought a pair of new ones from Rick at SS

 

[IvaTiger]

Mine measure .471 and .451 they both have very light surface rust and have been parked for 40 years Can they be resurfaced and still be good without issues and should they both be about the same thickness after machining or is one being .020 thicker okay

 

[0neoffive]

Mine measure .471 and .451 they both have very light surface rust and have been parked for 40 years Can they be resurfaced and still be good without issues and should they both be about the same thickness after machining or is one being .020 thicker okay

Obviously yours have been turned. Once thinned, they can fall victim to uneven pad pressure as one or more of the Girling calipers gather bore dirt and the pistons stick. This condition speeds warping. Best to simply replace them. Opinion # 47-2/3 rds

 

[IvaTiger]

From my very bad memory, is 1/2" not the new thickness?

A quick google search turned up:
The new rotors are .500 inch and the minimum is .375 inch. The data came
from a factory service bulletin. Hope this helps.

I just bought a pair of new ones from Rick at SS

We’re the new ones you just bought ready to install or did they require turning to true them up ? , I know 50 years ago that was required but new ones these days come ready to install on modern cars Thanks for your response.

 

[spmdr]

The Brakes on Tigers are high up on the Weak points of the car.

.375 is WAY too thin for a Tiger rotor!

Take ANY suggestion to turn them that thin with Block of salt!

DW

 

[IvaTiger]

The Brakes on Tigers are high up on the Weak points of the car.

.375 is WAY too thin for a Tiger rotor!

Take ANY suggestion to turn them that thin with Block of salt!

DW

I do agree that .375 is too thin I am assured that the new ones I have ordered are ready to be installed without any turning required like you had to do way back in the 60s. Thanks you all with advice and suggestions

 

[Hoghead]

The Brakes on Tigers are high up on the Weak points of the car.

.375 is WAY too thin for a Tiger rotor!

Take ANY suggestion to turn them that thin with Block of salt!

DW

I thought so too, but that is what the service bulletin apparently says. Then again I am only as informed as Mr Google
I did find another reference that was even thinner!!

 

[spmdr]

In my early Sunbeam days I found it VERY difficult to have the rotors turned

because the typical shop would NOT turn a rotor if it was not marked for a minimum thickness.

Or they had a reference in a book.

When I started using Japanese rotors on my race Tiger, they were marked for minimum thickness.

I don't remember the dimension, but it was metric and something like 11.8 mm.

But they were so cheap it was very little more money just to replace the rotors, so I never turned any.

 

[IvaTiger]

11.8 mm is .465 thousands and I believe the thickness of new ones is .500 so it would seam that turning them even with minimal wear would make them undersized and that may explain why they don’t have a minimum stamped on them , just chuck em away and start fresh !
Thanks for the input

 

[Warren]

It's amazing that some things aren't in the Sunbeam Specialties catalog. It took Rick a couple of years to add the AC housing.

My advice see how they fade. Get em hot and see what they do. How many panic stops will you make concurrently?

Some good comments would also evolve around what's your favorite brake pad?

 

[IvaTiger]

It's amazing that some things aren't in the Sunbeam Specialties catalog. It took Rick a couple of years to add the AC housing.

My advice see how they fade. Get em hot and see what they do. How many panic stops will you make concurrently?

Some good comments would also evolve around what's your favorite brake pad?

Do you even need brake pads if you are using stainless caliper pistons 😮

 

[Warren]

Well since the since the stainless steel pistons cost $90 I would think so
Although the hawk brake pads are pretty expensive.

 

[spmdr]

caliper piston as brake pad? It's customary to have a bit more surface area....

DW

 

[pfreen]

For other British cars like the TR6 which started with a .5" disc, the minimum disc thickness I found online is 45". I do not think .025" on each side would make any difference to braking or durability.

 

[Austin Healer]

I refuse to turn them anymore. As they are solid they hold heat and tend to warp after being turned/resurfaced. Besides they are cheap. These cars are now over 55 years old... The chances that the rotors have never been turned are nil. Most will have been turned several times. Most of the shops around here won't resurface a rotor if it doesn't have a min. thickness stamped into it, or they can't find a spec in their books.