What is facing a frame

Hi, a quick one. I read with interest the post about facing a frame a
few days ago. What exactly is facing a frame? I know what chasing the
threads in a bb but can someone give me a simple definition?

A shy person asked:

Hi, a quick one. I read with interest the post about facing a frame a
few days ago. What exactly is facing a frame? I know what chasing the
threads in a bb but can someone give me a simple definition?

This is one of the many technical terms explained in my online Bicycle
Glossary. See: http://sheldonbrown.com/gloss_e-f.html#facing

Sheldon "http://sheldonbrown.com/glossary" Brown
+------------------------------------------+
| On Monday, when the sun is hot, |
| I wonder to myself a lot: |
| 'Now is it true, or is it not, |
| 'That what is which and which is what?' |
| --A. A. Milne |
+------------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Me wrote in :
Hi, a quick one. I read with interest the post about facing a frame a
few days ago. What exactly is facing a frame? I know what chasing the
threads in a bb but can someone give me a simple definition?

Facing is shaving the outer edges of the bottom bracket to make them
perfectly parallel before you install the bearing cups. Same goes for the
head tube before you install the headset. This kind of work is less
important now than in the past.

Facing is shaving the outer edges of the bottom bracket to make them
perfectly parallel before you install the bearing cups. Same goes for the
head tube before you install the headset. This kind of work is less
important now than in the past.


In what parallel universe? Just as important today as itever was.

Grinding material from the outer faces of the bottom bracket shell to make
them level and parallel*. Park Tools have more info on their website.

the material is not ground but milled.
Phil brown

"Phil Brown" wrote in message
...
Facing is shaving the outer edges of the bottom bracket to make them
perfectly parallel before you install the bearing cups. Same goes for
the
head tube before you install the headset. This kind of work is less
important now than in the past.


In what parallel universe? Just as important today as itever was.

Some of the newer cartridge bottom brackets (like Phil Wood and others) use
mounting rings that don't contact the outer faces of the bottom bracket
shell, they just fit inside, so there is no point in facing the bb if you
are using one of these. If your bottom bracket tightens against the shell,
it's still needed. Likewise, all the headsets I have seen contact the faces
of the headtube so facing would still be needed here.
Lyle

On 2004-11-14, res09c5t wrote:

Some of the newer cartridge bottom brackets (like Phil Wood and others) use
mounting rings that don't contact the outer faces of the bottom bracket
shell, they just fit inside, so there is no point in facing the bb if you
are using one of these. If your bottom bracket tightens against the shell,
it's still needed. Likewise, all the headsets I have seen contact the faces
of the headtube so facing would still be needed here.

You still need to ensure that the BB threading is concentric. With French
and Italian threading, this isn't an issue: you can run a single tap in
one side and all the way through to the other, ensuring concentricity.
With English threading, you need to use a piloted tap set for this.

--

-John )

Quoth John Thompson:

You still need to ensure that the BB threading is concentric. With French
and Italian threading, this isn't an issue: you can run a single tap in
one side and all the way through to the other, ensuring concentricity.
With English threading, you need to use a piloted tap set for this.

I've heard this touted as an advantage of the wrong-way threading used
on old French and Italian bottom brackets.

However, I've worked on a LOT of French and Italian bikes, and have
never seen a bottom bracket that showed signs of having been threaded in
this manner.

Sheldon "Right Is Wrong" Brown
+----------------------------------------+
| All theory, dear friend, is grey, |
| but the golden tree of actual life |
| springs ever green. --Goethe |
+----------------------------------------+
Harris Cyclery, West Newton, Massachusetts
Phone 617-244-9772 FAX 617-244-1041
http://harriscyclery.com
Hard-to-find parts shipped Worldwide
http://captainbike.com http://sheldonbrown.com

Ken wrote in message ...
Me wrote in :
Hi, a quick one. I read with interest the post about facing a frame a
few days ago. What exactly is facing a frame? I know what chasing the
threads in a bb but can someone give me a simple definition?

Facing is shaving the outer edges of the bottom bracket to make them
perfectly parallel before you install the bearing cups. Same goes for the
head tube before you install the headset. This kind of work is less
important now than in the past.


I thought that it meant to stand in front of it and look straight at it.

Andres

andres muro wrote:
Ken wrote in message
...
Me wrote in :
Hi, a quick one. I read with interest the post about facing a frame
a few days ago. What exactly is facing a frame? I know what chasing
the threads in a bb but can someone give me a simple definition?

Facing is shaving the outer edges of the bottom bracket to make them
perfectly parallel before you install the bearing cups. Same goes
for the head tube before you install the headset. This kind of work
is less important now than in the past.


I thought that it meant to stand in front of it and look straight at
it.

Beat you to it by ~25 hours.

(And a bit better, IIDSSM.)

--
BS (no, really)

"B i l l S o r n s o n" wrote in message . ..
andres muro wrote:
Ken wrote in message
...
Me wrote in :
Hi, a quick one. I read with interest the post about facing a frame
a few days ago. What exactly is facing a frame? I know what chasing
the threads in a bb but can someone give me a simple definition?


Facing is shaving the outer edges of the bottom bracket to make them
perfectly parallel before you install the bearing cups. Same goes
for the head tube before you install the headset. This kind of work
is less important now than in the past.


I thought that it meant to stand in front of it and look straight at
it.

Beat you to it by ~25 hours.

(And a bit better, IIDSSM.)

OOOHPS! you're right. i'm slow on the uptake