• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Early spridget brake rotors

Share this page

rkep01

rkep01

Jedi Trainee
Offline
What is the minimum thickness that the rotors can be turned? Have a set that are not grooved, but they're well rusted and have some shallow pitting. Can they be just sandblasted and ignore the pitting? Or <span style="text-decoration: underline">must</span> they be turned? :confuse:
 
I will admit that I have used VERY rusty brake rotors before and all that I did was to drive carefully for about the first three stops and suddenly they were very clean and ready to use normally. If you do this and then they start to pulse then is when you should worry about blasting verses turning.
BillM
 
They should be 0.303"

You can face them down to 0.290"

I cut a set down to 0.285" by mistake, and they were still OK for a season of racing (but I'm not recommending this).
 
Billm said:
I will admit that I have used VERY rusty brake rotors before and all that I did was to drive carefully for about the first three stops and suddenly they were very clean and ready to use normally. If you do this and then they start to pulse then is when you should worry about blasting verses turning.
BillM
Click to expand...

Thanks, Bill. I thought of that, but I didn't know if it would work or not.
 
I used a set of old/pitted rotors when I first did the conversion. I put a set of EBC pads with the break in treatment on the surface and they cut in pretty good and removed most of the pits and rust. I but replaced them once the car was ready for full time use, a piece of mind thing.
 
aeronca65t said:
They should be 0.303"

You can face them down to 0.290"

I cut a set down to 0.285" by mistake, and they were still OK for a season of racing (but I'm not recommending this).
Click to expand...

Thanks Nial. I'll try Bill's method first. If, after that, the rotors need to be faced, I'll have that done. As I said in my original post, there is almost no wear that I can see. They appear to be new rotors that were installed on some car a while ago and just allowed to rust. They look awfully small compared to other rotors that I have worked with. Can any parts store do them or do they have to be sent to a specialist?
 
The cast iron rotors on my motorcycle used to rust up every winter and would be nice and shiny after I got back from the first ride. I never noticed any degradation in braking at the time.
 
I had 3 sets of rotors turned. Each by a different place that did brake work and and they all were ruined. There is no talent out there any more. If they don't work for you I recommend new. They are not expensive.

Kurt.
 
nomad said:
I had 3 sets of rotors turned. Each by a different place that did brake work and and they all were ruined. There is no talent out there any more. If they don't work for you I recommend new. They are not expensive.

Kurt.
Click to expand...

I agree! I don't have them cut any more either. When they go bad, I replace them. PJ
 
PAUL161 said:
nomad said:
I had 3 sets of rotors turned. Each by a different place that did brake work and and they all were ruined. There is no talent out there any more. If they don't work for you I recommend new. They are not expensive.

Kurt.
Click to expand...

I agree! I don't have them cut any more either. When they go bad, I replace them. PJ
Click to expand...

After checking eBay and the usual suspects, I'm beginning to agree with you guys. :iagree:
 
If they are for wire wheels I have a pile of new ones (still in boxes) from PaulA that I need to move along (for $5 each plus shipping). If anyone needs some (for wire wheels ONLY) tell me.
BillM
 
Drat! Steel wheels.
 
Billm said:
If they are for wire wheels I have a pile of new ones (still in boxes) from PaulA that I need to move along (for $5 each plus shipping). If anyone needs some (for wire wheels ONLY) tell me.
BillM
Click to expand...

Hey Bill, my luck, I could use a set!

Kurt.
 
Bill, I plan to transfer the wire wheel setups from my parts car to my Bugeye so I'm sure I could use new rotors if they are right for it.
 
Sounds like Kurt will get 2, Rick will get 2 and Mike will get 6- looks like they are now all gone.
BillM
 
BillW103 said:
I had a set of rusty rotors and I couldn’t find any one to turn them. They wouldn’t fit on the machine.
Click to expand...

:iagree: Yeah, that's what I thought. They're too small.
 
rkep01 said:
What is the minimum thickness that the rotors can be turned? Have a set that are not grooved, but they're well rusted and have some shallow pitting. Can they be just sandblasted and ignore the pitting? Or <span style="text-decoration: underline">must</span> they be turned? :confuse:
Click to expand...

If they are just rusty and are not warped or have excessive runout, put an 80 or 100 grit sanding disc in your drill and scuff them. They'll be fine. If you nervous about doing that for some reason, brush them with phosphoric acid, keep them wet for 30 minutes to an hour and then take a coarse wire wheel to them. The cast iron will make a bit of a stink, but they'll clean up fine.
 
Back
Top