Topic: Brake Disc Question of the Day

[oldhatt45]

About to finish up putting my front wheel.
But before I do it, I was wondering about whether I should try to do a little surface finishing of the Front Rotor.  I did a forum search and looked at the How-To section but all that was there was a short video of one of the guys here putting their rotor on a lazy susan and using what looks like a dremel or rotozip with a sanding disc maybe. 

Was hoping to find some info on resurfacing the Rotor.  Would appreciate any tips, or info on how to do it.

Thanks,

Charlie

[754]

Blocksanding with sandpaper on a lathe works very well,  if there is no deep grooves..minor stuff seems to come out.
 Hard part is getting a lathe to use, I abhor the use of sandpaper or emery on my best lathe for a few reasons.. First a thorough clean up and see due afterward, and second its a lathe killer.
 But covering the ways and carriage with paper or cardboard...wrapping chuck with saran or shrink wrap helps  a lot.

[oldhatt45]

754,

Thanks. 

What grit sandpaper to use???
Don't have access to a lathe, but I have some long block sanders that I used when working on fiberglass boats.

Rotor is not bad and has no "scratches", but I would like to clean it up a bit.
I think I've got plenty of Rotor left.  It measures 7mm, so not worried about taking material off.

Charlie

[edwardmorris]

Get it Blanchard ground, takes off next to nothing and comes out pretty. Member Godffrey now offers this service too

[754]

Might be able to spin it in a drill press if you make an adaptor.. ..not too fast ..support other end..
Probably 220 or 320 grit..

[oldhatt45]

754,

Thanks, that's a good idea.
Also appreciate the info on the grit of sandpaper.

What about using a DA sander?  All I basically want to do is to give the rotor a fresh surface.  Almost like just breaking the "glaze".

Edward,
I'll have to check and see if I can get a Blanchard grind done.  Thanks.

Charlie

[edwardmorris]

The machinist that did mine cautioned against DIY, unless you have a really good set up to keep the rotor "true" by the time you're done with it. Blanchards have micro something accuracy, where as any manual sander/ing will be far from it. I'd send it to Godffrey, or at least have a chat with him before a DIY attempt. My $0.02 of course.

[754]

You would be hard pressed to remove 2 thou a side with the sanding, as long as it keeps turning while sanding.. The big plus is it generates a stock looking finish, which some other methods do not.
 DA might help just be sure to lift off slowly..

[Airbusboy]

I've also got the rotor on my '74 CB550 that I'd like polished while I have it off this winter getting the wheel trued. How do I/we reach the infamous 'Goddfrey' to have him do his magic on the rotor?  Thanks, guys!

[Paul Lowe]

I went the lathe method with flap sander on a cordless drill. Came out perfect and it had some nasty scratches.

[jmelche2]

I've also got the rotor on my '74 CB550 that I'd like polished while I have it off this winter getting the wheel trued. How do I/we reach the infamous 'Goddfrey' to have him do his magic on the rotor?  Thanks, guys!

Yes, I'd like to find out more about this member.  How do we contact him and where is he located? 

[Oldtech]

Here in Ottawa we have a company called General Grinding that does that sort of work at a reasonable price. Check around in your area. There has to be someone doing it.

[flybox1]

I've also got the rotor on my '74 CB550 that I'd like polished while I have it off this winter getting the wheel trued. How do I/we reach the infamous 'Goddfrey' to have him do his magic on the rotor?  Thanks, guys!

just visit his garage    I'm running two of his drilled 4mm rotors.  good stuff!

http://www.vinmoto.org/gallery/v/VinMoto-Garage/album03/Godfferys-Garage-123/Parts+and+service/

[754]

I would caution about putting it on a bench grinder.. For a few reasons..
 First being. The rotor is not designed to turn at those RPMs, if the carrier fails, the next two or three seconds will get very ugly..

 If you try putting on a drill press, make sure the speed is low enough.. Some small ones are too fast, plus the machine is too light should there be some imbalance.
 And it's easy to not have it running true without a purpose machined adaptor

[edwardmorris]

I've also got the rotor on my '74 CB550 that I'd like polished while I have it off this winter getting the wheel trued. How do I/we reach the infamous 'Goddfrey' to have him do his magic on the rotor?  Thanks, guys!

just visit his garage    I'm running two of his drilled 4mm rotors.  good stuff!

http://www.vinmoto.org/gallery/v/VinMoto-Garage/album03/Godfferys-Garage-123/Parts+and+service/

Or PM him, http://forums.sohc4.net/index.php?action=profile;u=7132

[Dunk]

I just did quick and dirty with a line sander. Forget what grit, probably 80 then 120 or 150. Not perfect but much better than it was. Just kept it spinning on my bench and going around it with the sander.

[dave500]

ive deglazed them with a big flat sharpening stone and soapy water over a couple of beers worked fine,ive also laid a trolley on its side with the disc sat on a wheel and spun it while I shot it with the sand blaster worked well,its hard material.

[oldhatt45]

OK, so with all that was said,I took my rotor down to the local machinist and ask him if he could just reface the rotor.  Dropped it off just before lunch.  He said if he could mount it up on his machine then no problem.  Got home, just finished lunch and the phone rings.  It's the machinist.  He said "come get your rotor".  Wasn't sure whether he was able to do anything, so went and picked it up.  Perfect.  He only took off 0.14mm.  Went from 6.99mm to 6.55mm.  All for $13.00.

Oh, and I did things a little bass akwards.  I just have to wire wheel some light rust spots off and maybe touch up the paint.  Next Rotor will do in correct sequence. 

Did I do OK with this Rotor?

Thanks,

Charlie

[dave500]

yep that's cheap.

[Retro Rocket]

yep that's cheap.

+1 

[754]

That wood be cheap at double the price..is it both sides..

[oldhatt45]

754,

Yep, both sides.  Other side looks the same as the one in the picture.

Thanks Guys,

Charlie

[edwardmorris]

Good deal! Looks pretty close to a Blanchard finish.

For the surface rust on the center, steel wool and diet coke work great. I did my initial cleaning of all chrome parts that way, was shocked how well it worked. Diet won't leave it sticky, and works just as well as regular. Its the phosphoric acid that helps..

[dave500]

they would want 15 bucks to set it up here let alone actually machine it!

[Stev-o]

Very good deal.  I suggest painting the entire middle section rather than touch up. Use caliper paint.

[750cafe]

I just recently did my Kawasaki rotors. This was the worst one.


Almost finished.


Finished and waiting for the paint to dry.


Sorry, no finished/mounted pictures yet as my broken hip slowed down progress. 
Staples get pulled this Friday.

Eric

[oldhatt45]

Edward,
Thanks for the tip on cleaning up the centers!!!!!

Dave500,
I have 4 more rotors to do and after seeing the finished caliper I told the machinist, and he said if I brought all 4  in at the same time, he would do a bit better.  

Stev-O,
I'm thinking about doing the whole center.  Not sure yet whether I want it to look completely original or not.  But still thinking.

eric,
Sorry about the hip.  But the rotor is looking good.

Thanks,

Charlie

[750cafe]

I hobbled down the stairs and got a picture of the finished/mounted rotor for my latest mad-scientist project today.
I got some dirt on it rolling it to get the pic.



Eric

[oldhatt45]

Eric,

That rotor (and the Wheel) are looking Good.
Hope you're doing your Rehab on that Hip!!!!!!
That is the most important thing you can do.

Thanks,
Charlie

[alacrity]

Chris Schuman up in Portland Oregon does really stellar work. I had the discs "surfaced" by him - he has some huge machine for doing this in a pro machine shop.

It wasn't long before the pads made a a bit of a visual mess of his work, but they stop beautifully/predictably and don't squeal.  There is 500 miles on the new right side one.... 4000miles on the left side one.

here is the link to his ebay ad where you buy his service, send your rotor(s), he does the work and sends it back

http://www.ebay.com/itm/HONDA-CB500-CB550-CB650-CB750-BRAKE-DISC-ROTOR-SERVICE-/300736155448?pt=Automotive_Services&hash=item4605458f38

[750cafe]

Eric,

That rotor (and the Wheel) are looking Good.
Hope you're doing your Rehab on that Hip!!!!!!
That is the most important thing you can do.

Thanks,
Charlie

Thanks for caring. I get the staples out in two days. Surgery was a week ago Sunday morning. Motorcycles ARE THERAPY. 

[oldhatt45]

Eric,
The most dangerous time for hip replacements is the 2 to 6 week time period when the bones are attaching themselves to the new parts.   My better half had both hips done 8 weeks apart.  The Dr. told her that the new hip joint has to settle into place and that she might feel a little "squishing" (LOL) as the parts seat themselves in final position.  That's the reason the rehab is so important, cause it makes the parts seat correctly with all the different movements you are likely to do.

Kind of like the Chain seating itself on the sprockets and grinding off the rough finish although there is no rough finish on the new hip parts.  LOL  I know you'll do fine as long as you do the rehab.

And you're right, Motorcycles are Therapy, but not the complete answer in all cases.

Charlie

[750cafe]

It is not a hip replacement. I did a flying leap and landed on the left hip breaking the bone at the top. Some screws and a steel plate were installed the next morning.
I am just going stir crazy waiting around for these damn staples to get removed so that I can continue to heal up. Tomorrow, a couple of ski resorts open around here.
I am pretty sure that my Doctor will think I am crazy when I suggest going skiing after he removes the staples. LOL! I WILL make him wonder about me though.      
Got to keep them guessing...

Eric

[oldhatt45]

Eric,
ROFLMAO!

People often wonder about me too! 

Well, just don't do anything really dumb.  LOL

And watch those flying leaps. 

Charlie

[750cafe]

While in the hospital, the nurses placed some kind of inflatable cushion under me to keep from getting bed sores or something.
They called it a waffle. I asked them to use the real maple syrup and not that cheap corn syrup crap. 

Eric

[oldhatt45]

FUNNY!!!!!
I might add, it's not a Waffle.  They really set you up with a Whoopie Cushion!
Hahahaha

Charlie

[grcamna2]

OK, so with all that was said,I took my rotor down to the local machinist and ask him if he could just reface the rotor.  Dropped it off just before lunch.  He said if he could mount it up on his machine then no problem.  Got home, just finished lunch and the phone rings.  It's the machinist.  He said "come get your rotor".  Wasn't sure whether he was able to do anything, so went and picked it up.  Perfect.  He only took off 0.14mm.  Went from 6.99mm to 6.55mm.  All for $13.00.

Oh, and I did things a little bass akwards.  I just have to wire wheel some light rust spots off and maybe touch up the paint.  Next Rotor will do in correct sequence. 

Did I do OK with this Rotor?

Thanks,

Charlie

They did a nice job at your machine shop;I've had machine shops put my disc's on their automotive flywheel cutting machine and do a nice light cut similar as yours is.They stop a lot better w/ those swirls too 

[oldhatt45]

grcamna2

I'm not sure if he put my rotor on his flywheel cutter or not.
He did mention that he started getting some vibration as he got out toward the outer edge and had to change his setup.  He also said the Rotor was nice and Flat (I was worried about possible warping).
So, all in all I'm happy for several reasons.  First that I have a nice refaced rotor. Next, that I didn't get ripped off. And that he knows what he's doing.  And Last but not least, that you guys all think the resurfaced rotor looks the way it should.

Thanks,

Charlie