|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Disc Rotor Refurb?
A new 6" rotor is only about twenty bucks, but I've accumulated a
few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? -- PeteCresswell |
Ads |
#2
|
|||
|
|||
Disc Rotor Refurb?
PeteCresswell wrote:
A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? Scotchbrite? Wet-or-dry silicon carbide paper? Brake cleaner spray? All of the above? It sounds to me like your rotors have some tenacious lubricant residue on them, and if you can remove the residue or the surface upon which it's deposited, you'll be back in business. Chalo |
#3
|
|||
|
|||
Disc Rotor Refurb?
On 15 Jan, 22:27, "(PeteCresswell)" wrote:
A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? No, but if you want to degrease use washing soda or caustic soda. Dont ever use with aluminium unless you keep the contact time short. |
#4
|
|||
|
|||
Disc Rotor Refurb?
On 1/15/2010 4:27 PM, (PeteCresswell) wrote:
A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? For $50 each plus shipping, I can make them work like new. -------- Seriously, it would be interesting to see exactly what the problem is. To make sure they're not warped, you would need....... a machine shop. You coat one side with dye (or just draw a grid on it with a permanent marker) and then scoot it around gently on a granite flat, and any "high" spots will have the marking ink rubbed off before everywhere else. ~ |
#5
|
|||
|
|||
Disc Rotor Refurb?
DougC wrote:
On 1/15/2010 4:27 PM, (PeteCresswell) wrote: A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? For $50 each plus shipping, I can make them work like new. -------- Seriously, it would be interesting to see exactly what the problem is. To make sure they're not warped, you would need....... a machine shop. You coat one side with dye (or just draw a grid on it with a permanent marker) and then scoot it around gently on a granite flat, and any "high" spots will have the marking ink rubbed off before everywhere else. ~ The classic way to get a cheap flat surface (i.e. for lapping) is to use some plate glass. I've checked auto heads/blocks for flatness with a ground (e.g. Starrett) straightedge (~$10). |
#6
|
|||
|
|||
Disc Rotor Refurb?
Peter Cole wrote:
DougC wrote: On 1/15/2010 4:27 PM, (PeteCresswell) wrote: A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? For $50 each plus shipping, I can make them work like new. -------- Seriously, it would be interesting to see exactly what the problem is. To make sure they're not warped, you would need....... a machine shop. You coat one side with dye (or just draw a grid on it with a permanent marker) and then scoot it around gently on a granite flat, and any "high" spots will have the marking ink rubbed off before everywhere else. ~ The classic way to get a cheap flat surface (i.e. for lapping) is to use some plate glass. I've checked auto heads/blocks for flatness with a ground (e.g. Starrett) straightedge (~$10). yup, I have trued up oil pump covers using a piece of thick plate glass and some wet/dry sandpaper (not having a milling machine in my garage.) Ought to work for rotors as well, I'd be a little worried about the thinness of the metal however, the rotor might actually flex while you're sanding it, so I can't guarantee you'll get perfect results. nate -- replace "roosters" with "cox" to reply. http://members.cox.net/njnagel |
#7
|
|||
|
|||
Disc Rotor Refurb?
Chalo wrote:
PeteCresswell wrote: A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? Scotchbrite? Wet-or-dry silicon carbide paper? Brake cleaner spray? All of the above? It sounds to me like your rotors have some tenacious lubricant residue on them, and if you can remove the residue or the surface upon which it's deposited, you'll be back in business. Chalo Brakleen or Berkebile 2+2 (carb cleaner) are great solvents when everything else fails. I always have a can or two around even if I'm working on something non-automotive. nate -- replace "roosters" with "cox" to reply. http://members.cox.net/njnagel |
#8
|
|||
|
|||
Disc Rotor Refurb?
On 16 Jan, 16:13, Nate Nagel wrote:
Peter Cole wrote: DougC wrote: On 1/15/2010 4:27 PM, (PeteCresswell) wrote: A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? For $50 each plus shipping, I can make them work like new. *-------- Seriously, it would be interesting to see exactly what the problem is. To make sure they're not warped, you would need....... a machine shop. You coat one side with dye (or just draw a grid on it with a permanent marker) and then scoot it around gently on a granite flat, and any "high" spots will have the marking ink rubbed off before everywhere else. ~ The classic way to get a cheap flat surface (i.e. for lapping) is to use some plate glass. I've checked auto heads/blocks for flatness with a ground (e.g. Starrett) straightedge (~$10). yup, I have trued up oil pump covers using a piece of thick plate glass and some wet/dry sandpaper (not having a milling machine in my garage.) * Ought to work for rotors as well, I'd be a little worried about the thinness of the metal however, the rotor might actually flex while you're sanding it, so I can't guarantee you'll get perfect results. On the car I've used a file applied to the disc with the engine running to remove the overhang at the edge. For a disc still fitted a similar method could be employed on a bicycle say using a drill chuck applied to the tyre to turn the wheel and an abrasive pad against the disc. |
#9
|
|||
|
|||
Disc Rotor Refurb?
thirty-six wrote:
On 16 Jan, 16:13, Nate Nagel wrote: Peter Cole wrote: DougC wrote: On 1/15/2010 4:27 PM, (PeteCresswell) wrote: A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? For $50 each plus shipping, I can make them work like new. -------- Seriously, it would be interesting to see exactly what the problem is. To make sure they're not warped, you would need....... a machine shop. You coat one side with dye (or just draw a grid on it with a permanent marker) and then scoot it around gently on a granite flat, and any "high" spots will have the marking ink rubbed off before everywhere else. ~ The classic way to get a cheap flat surface (i.e. for lapping) is to use some plate glass. I've checked auto heads/blocks for flatness with a ground (e.g. Starrett) straightedge (~$10). yup, I have trued up oil pump covers using a piece of thick plate glass and some wet/dry sandpaper (not having a milling machine in my garage.) Ought to work for rotors as well, I'd be a little worried about the thinness of the metal however, the rotor might actually flex while you're sanding it, so I can't guarantee you'll get perfect results. On the car I've used a file applied to the disc with the engine running to remove the overhang at the edge. For a disc still fitted a similar method could be employed on a bicycle say using a drill chuck applied to the tyre to turn the wheel and an abrasive pad against the disc. What do you gain by filing the overhang? |
#10
|
|||
|
|||
Disc Rotor Refurb?
On 16 Jan, 20:53, z wrote:
thirty-six wrote: On 16 Jan, 16:13, Nate Nagel wrote: Peter Cole wrote: DougC wrote: On 1/15/2010 4:27 PM, (PeteCresswell) wrote: A new 6" rotor is only about twenty bucks, but I've accumulated a few rotors that *look* ok, but pulse badly. Tried boiling in water for awhile on the latest one, but no change. I thought sand blasting for a moment, and then it seemed like that would be asking for irregularities in thickness. Anybody got a tried-and-true method of refurbishing a rotor that doesn't require a machine shop? For $50 each plus shipping, I can make them work like new. *-------- Seriously, it would be interesting to see exactly what the problem is. To make sure they're not warped, you would need....... a machine shop. You coat one side with dye (or just draw a grid on it with a permanent marker) and then scoot it around gently on a granite flat, and any "high" spots will have the marking ink rubbed off before everywhere else. ~ The classic way to get a cheap flat surface (i.e. for lapping) is to use some plate glass. I've checked auto heads/blocks for flatness with a ground (e.g. Starrett) straightedge (~$10). yup, I have trued up oil pump covers using a piece of thick plate glass and some wet/dry sandpaper (not having a milling machine in my garage.) * Ought to work for rotors as well, I'd be a little worried about the thinness of the metal however, the rotor might actually flex while you're sanding it, so I can't guarantee you'll get perfect results. On the car I've used a file applied to the disc with the engine running to remove the overhang at the edge. *For a disc still fitted a similar method could be employed on a bicycle say using a drill chuck applied to the tyre to turn the wheel and an abrasive pad against the disc. What do you gain by filing the overhang? Absence of annoying scraping noise. This was still while the disc was within manafuacturers limit of servicable thickness but only just. If the disc has been re-fitted (bike) then it is possible that the pads will run on and off an old wear track so creating unwanted braking modulation. Although the real answer is to ensure the disc is fitted concentrically with the wheel I cant see a little abrasion to even things up doing any harm. |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
FS: Hope 5 hole Disc Rotor | Dawgwalker | Marketplace | 0 | November 22nd 05 11:17 PM |
Disc Rotor Question | Sscarich | Techniques | 5 | October 2nd 04 02:18 AM |
Custom singlespeed disc rotor | spademan o---[ * | Mountain Biking | 18 | October 30th 03 04:22 PM |
disc brake rotor size, 6 or 8? | Colin Song | Mountain Biking | 9 | October 28th 03 10:35 PM |
Disc brake rotor size | Michael | Techniques | 9 | July 14th 03 04:43 AM |