AirChair

Hello, I am currently in the process of fully tearing down my campy Brakes and polishing them. I am hard stuck right now with the issue of removing the nut that secures (Ive attached a schematic to make it clear what i mean, and wrote the Part names)Br-Re015 to Br-Re002. The Nut has a securing screw which i have removed. On another Thread(campy-brake-disassemble-help) someone was having similar issues and was given some advice but he never said if it worked for him. I've done everything, Using Heat using penetrative oil and just force, but nothing was able to get the nut to budge. Furthermore i found that the Threads on bold seem to have been damaged by the securing screw. Below are Images of the part and the damaged theads on the bolt.

If anyone has any advice for me i would greatly appreciate it.

Airchair
ibb. co/ vZ985kG
ibb. co/ ws1b93X
ibb. co/ d6nwygQ
ibb. co/ r035cpG
ibb. co/ C1SFspH
ibb. co/ qJrdy3Z
Had to do some tirckery to sneak the url for the images through(Sorry mods) just remove the spaces

Andrew R Stewart 

Sorry but was unable to open up and view the photos (the links asked me to sign up for an account which I don't do to just look at stuff). I tried a google search for the BR-RE105 part and believe you have a dual pivot side pull brake (and these are no where near "vintage" status yet being still used design wise). I also think the stuck screw is in the plate that the holds the arms' pivots and is to insure the pivot bolts don't self loosen. Shimano and other dual pivot calipers use the same design. These set screws can become stuck in place from overly strong thread locking compounds used during initial assembly or corrosion built up over the years. Many have a tiny allen wrench fitting for their heads and the wrench's fit can lack the strength to not "strip out" during removal attempts.

How much heat have you tried? Did you use an oven or a hair drier? Yes, these types of retention screws do bare against threads with enough pressure to slightly damage that thread where the screw contacts it. Of course, if the bolt is removed with the screw still in place that damage can "travel" as the bolt is unthreaded. Cleaning up the bolt's threads might be easy, chasing the threads with a die is the usual method. Can you do the polishing w/o removing the screw? Is there a backing nut to additionally secure the pivot bolt? If so than the screw is somewhat redundant. Andy

curbtender

Pic assist

3alarmer 

.
...the part I'm missing in this is why you are taking them apart ? What are you trying to accomplish ? I have rarely needed to disassemble a bicycle brake caliper, and I've worked on some that were pretty filthy. It's a mistake to take them apart just to clean them.

Iride01 

The OP said polish, not just clean.

Mr. 66

Pull the set screw from the mounting arm. The nut with the two flats locks to the mounting arm. The mounting arm is threaded to the center bolt with a washer between the two. You may need to get a better grip on the little arm to break free. If there is no set screw the arm and the are just friction locked so the center/pivot bolt has no bind in the pivoting.

3alarmer 

...the ones I've had are already pretty well polished from the original manufacturer. If you really needed to gild the lily, the visible surfaces on the exterior are all accessible without disassembly. So yeah, I still don't get it. A couple of cycles in an ultrasonic cleaner, with the brake shoes removed, a little dry lube with ptfe in the pivots, and new shoes if needed, and they come out looking pretty spiffy.

AirChair

While yeah they are polished pretty well from the manufacturer, but the thing is im trying to polish them to a mirror finish, will it improve my riding no, but thats not the point. These Parts come anodized from the factory meaning to polish them you have to get that initial anodization off using either Chemicals or just abrading them away. Using things like oven cleaner makes it pretty easy and quick but i don't want the little ball bearings for which you cant buy any replacement to be ruined(as they are plastic) and if i would go the long route of sanding through the anodization i feel like i would fill those moving pivot points with tons of small aluminium particles which would work as abrasives. So thats why im trying so hard to get the nut off. Also im kind of a perfectionist when it comes to my bike in a way that i just love working on it understanding every part and wanting it to be perfect, in the same way like someone who restores junk old timers.

AirChair

Hello Andy.

here i put the images on another sharing service so you too could see them as i think they could make things more clear.
postimg.cc /gallery /WJxQ56m
...............^......... ^ remove these spaces

To answer your questions about heat, ive put it over my stove until it was difficult to hold it with my bare hand ergo, the heat traveled through the whole part. Also the thing is that im scared of stripping of the screw(not the nut) and then id be f**ed. After posting this I decided to try to take my other brake apart to see if anything was different and the only thing i could find was that there seemed to be some kind of "fabric" sticking out of the threads. Maybe some kind of lock hemp idk?

In my view it is a vintage part since it is almost 30 years old and always listed as a vintage part but maybe since im still young things seem much older to me.

Anyway i hope my answers could help out a little and clarify things.

Airchair

Iride01 

Till you get 10 posts and a day or whatever it takes, you can also upload pics to the Galleryhere on BF.


https://ibb.co/vZ985kG

https://ibb.co/ws1b93X

https://ibb.co/d6nwygQ

https://ibb.co/r035cpG

https://ibb.co/C1SFspH

Mr. 66

Have you tried PB Blaster? That stuff soaks in well. I'm thinking no matter what it still may be a stiff start.

3alarmer 

...thanks for your reply. I'm not going to sit here and type out some argument, but anodizing got put on there for some pretty good reasons. And once you strip it off and polish your calipers, they will immediately begin to form the aluminum oxide coating that will eventually defeat your effort at a mirror surface, without regular maintenance. Best wishes with your project. I hope it comes out like a chrome Paramount.

I know that there are people on this forum who insist on removing the factory lubricant on a new chain, so they can get it "properly lubed". I am not one of these people.