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Jeff Weir
11-07-2007, 04:44 PM
A few weeks ago I ended up dragging one of my wheels underneath my car (flame away). The braking surface has some light scratches/rough areas which I would like to smooth out if possible. Are there any techniques for doing this? I tried steel wool but it didn't do very much.
Thanks in advance
Jeff

maunahaole
11-07-2007, 04:49 PM
green scotchbrite pad. clean afterwards with alcohol - scotchbrite has metal (Al, I think) oxide in it as an abrasive, you want to remove that afterwards.

dave thompson
11-07-2007, 04:52 PM
A few weeks ago I ended up dragging one of my wheels underneath my car (flame away). The braking surface has some light scratches/rough areas which I would like to smooth out if possible. Are there any techniques for doing this? I tried steel wool but it didn't do very much.
Thanks in advance
Jeff
Fine pumice stone? What I would try would be to mount the wheel, without the tire mounted, on the bike and hand pedal holding the pumice stone gently on the affected braking surface. I'd finish off with a green Scotchbrite cloth.

Dragging a wheel under your car?!?!? Jeff, what are we going to do with you? :cool:

Pete Serotta
11-07-2007, 05:14 PM
green scotch brite....It really depends on how deep they are..... and how wide. They might be ugly but if just scratches and you get the "high" marks off - the braking will be fine.


PETE

dvancleve
11-07-2007, 05:18 PM
I would use maybe 100 grit wet/dry sandpaper. Wet it and sand carefully and you should get things smooth enough for tolerable braking without removing too much metal or making it too ugly.

Doug

A few weeks ago I ended up dragging one of my wheels underneath my car (flame away). The braking surface has some light scratches/rough areas which I would like to smooth out if possible. Are there any techniques for doing this? I tried steel wool but it didn't do very much.
Thanks in advance
Jeff

stevep
11-07-2007, 05:38 PM
fine emory cloth

guyintense
11-07-2007, 06:06 PM
220 grit is as coarse as you should go. Support the paper with a hardwood block to keep the rim flat. Don't focus only on the scratched area, sand on each side of the effected area or you will end up with a pronounced divot. I cut a couple of small strips of scotch brite, put them between the pads and the rim and ride around the shop with the brakes on. While you're at it sand the pads a little too.

Ozz
11-07-2007, 06:29 PM
A few weeks ago I ended up dragging one of my wheels underneath my car (flame away)....

They make less noise and you can drive faster if you put them in the car....... ;)

So, I missed the part about how they ended up under the car.....details please so you can be properly mocked.....

Peter P.
11-07-2007, 08:44 PM
Here's what you do: Hold on to the steel wool. Buy sandpaper in various grades like 400, 280, 180, 100. In the current grit system that works out to Extra Fine, Very Fine, Fine, and Medium.

Start with 400 and sand the area for one minute. If you don't see results, move to the next COARSER grit. Repeat the process until you find a grit that begins to remove the scratches. The reverse direction and proceed back towards the finer grits. Finish with the steel wool.

I discovered this method while trying to remove scratches from a seatpost. 00, 0, 1, and 2 grade steel wool didn't touch it. 400 grit sandpaper did. Then I proceeded back to the steel wool, first with the coarser #2, and then the 1, 0, and finished with the 00. The scratches are gone and the polish is amazing.

I'll bet it works for your rim, too.

dirtdigger88
11-07-2007, 08:45 PM
http://www.dansdata.com/images/tools/dremel500.jpg

jason

Jeff Weir
11-07-2007, 09:35 PM
I was loading the bike on the roof rack and left the front wheel resting against the rear bumper. I start to back out of the driveway I hear this sound and begin to think, man, my transmission is really f'd up. Then I realize what the sound really is....

What's even more idiotic is, a couple of years ago, I'm loading my bike late at night, rear wheel against back bumper again, and I DRIVE AWAY!!!!! Wheel sleeps in the parking lot. The next morning I realize what I had done, drive 1 1/2 hours back and the security guard found it and had it in the trunk of his car.

And you folks thought Kevan was a moron? He looks like a Brain Surgeon compared to me.

Thanks for all of the advice!!!!!

Louis
11-07-2007, 10:19 PM
I was loading the bike on the roof rack and left the front wheel resting against the rear bumper. I start to back out of the driveway I hear this sound

This is why I lean my front wheel against the side of the car. Still didn't prevent me from driving away once. Ever since, I lean it against the driver's side...

Too Tall
11-08-2007, 06:07 AM
Bub, how deep are those scratches? Too deep to buff out?

Kevan
11-08-2007, 07:29 AM
And you folks thought Kevan was a moron? He looks like a Brain Surgeon compared to me.


I've been quiet about this whole thing, not sending you an emails laughing at you; no pm's asking if you are the jerk; no rushing over to your house, making sure your family is safe from your more dangerous antics and then I get this compliment posted for the world to see...

But that's okay...no hard feelings... (much)

In fact, I'm going to share with you my story about my messed-up rim, except my story has a lot more excitement than yours. See, I was riding over to Bedford from home to meet up with a club ride scheduled that morning. I was going through Mt. Kisco and traveling on route 172 and all was going hunky-dory, in fact, I was riding too fast (get that?!) and was going to arrive at the meeting place about a half hour too early. Anyway, as I was approaching the 684 overpass my front wheel dropped into the crack between two concrete slabs that made up the roadway there. I don't know how I avoided getting pitched, but due to my expert skills in riding I managed to stay upright and brought the bike to a noisy and very rough stop. My heart was trying to leap out of my chest. My brake surfaces were scarred something awful. So I did basically what Dave recommended, I found myself a couple stones (yeah...no, I already have those) of different smoothness and began working on the rim. I'd say that within about 15 minutes of working on the wheel I got it about 90% improved and was able to do the ride and ultimately run that rim for another year, into the ground, well used and well spent.

I've also left a front wheel behind in a parking lot. Course, mine was only 15 minutes away.

toaster
11-08-2007, 08:27 AM
Here's a trick I learned watching my car mechanic turn my brake rotors with a slight adaptation:

Using a Dremel tool with a flat adhesive sanding disc and getting your bike wheels without tires mounted in a truing stand or left on the bike held in a bike stand you then start by spinning the wheel and apply the Dremel's sanding disc to the braking surface of the rim. Soon it will become apparent whether the turning tool is working against the direction of wheel spin or with it. You want it to work with the direction of spin.

You soon end up with a new surface that has a machined look that has ground down the directional braking scratches and now because of the new direction of the sanding tool pattern the resurfaced rim will begin to break off some brake pad glaze as the two surfaces (aluminum and pad) work together and become smooth again.