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Discussion Starter · #1 · (Edited)
Well I needed a new BB for my cross veloce because of a creak ,

Anyway I did alot of the work my self since I been going there along time, well the threads needed to be chased so he took out that 400$ park tool chased them, that came out nice, but then he wanted to face it, well the aftermath of it was variable chizel type marks on the shell outer surface, I have never done it my self but it does not seem right, I would think it would have a smooth finish on it.

Anyone done this type of thing to know how it would be done, or if it was done wrong? The frame is Scandium & carbon stays






 

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Can you feel the surface with each of those marks...does it feel wavy?

I've done some metal work the past 10 years and there are times when using certain countersinks that I will get similar when the bit chatters. On a low spec part...no big deal. Yeah, it doesn't look nice but so long as the width of the shell is in tolerance and parallel, I'd think you are ok.

Just looked at Park's page about this:
http://www.parktool.com/products/detail.asp?cat=25&item=BFS-1#

I can see how this tool left those marks behind. Is this an aluminum frame?
 

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Whoever did that to your frame should never have let you leave the shop with the shell looking like that. If I did that to a customer's frame, you can bet the shop would be compensating him or her.
Here's what to do: use calipers to measure the shell width, and try and do so where the teeth gouged the shell deepest. BB shells are wider than they should be when the frame is built, and if they weren't faced properly to begin with (and they often aren't), then you may have a millimeter or so to work with. A wrench who knows what he is doing can probably face the shell properly with it in that condition. If the shell is already 68 or 73 mm or fewer, and if you are not going to be using an outboard bb, then at least the frame can be ridden. I would definitely be in contact with the shop about fixing the problem, though.
 

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Yes, the wrench messed that up. Too much pressure on the spring, chattering, who knows.

Anyway...the BB does not have to be exactly 68mm. there is some allowable variation + / - from 68mm. For instance the new Campy ultra torque Crank works with a BB shell width of 67.2 mm to 68.8 mm.

So technically yours could still be saved if someone can take their time and still get a flat shell out of that. Good luck.
 

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ouch! that is really ugly....but one possible solution if refacing does not work out would be to use a Phil Wood BB, the lockrings only use the threads so the faces don't matter...maybe the shop that mangled the frame could pay for one
 

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If you read the directions for the use of the park facing tool it says chatter marks are just cosmetic so you may not get the satisfaction you wish from your local LBS.

6. Continue to rotate the handles several complete turns, then stop to check progress. Loosen
tension nut then pull facing cutter back to view bottom bracket shell. If the objective of the
operation is only to face the bottom bracket shell, remove only enough material to expose
a fresh cut completely around the face of the shell. If the objective is to reduce the width of
the bottom bracket shell, continue facing until the predetermined amount of material has
been removed. Measure the bottom bracket shell width regularly to avoid cutting too much
material. Due to a combination of factors (ex. the type of material being faced, the amount
of spring pressure used, the type of cutting fluid used, etc.) “chattering” marks may appear
on the finished surface. This “chattering” is cosmetic only and does not affect the function
of the bottom bracket.

As a machinist I find this unaceptable-cutter was dull and or inproper pressure used.
 

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I agree. The bike is fine. The wrench that worked on you bike needs some lessons on how to use that tool.
As cotton said, the tool is probably dull.
 
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