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Old January 11th 17, 01:11 AM posted to
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Default Need advice on bottom bracket repair

Benderthe.evilrobot wrote:

"Duane" wrote in message
On 10/01/2017 4:13 PM, AMuzi wrote:
On 1/10/2017 1:52 PM, wrote:
On Tuesday, January 10, 2017 at 11:36:41 AM UTC-8, Benderthe.evilrobot
"Jeff Liebermann" wrote in message
On Mon, 9 Jan 2017 22:24:41 -0000, "Benderthe.evilrobot"

"Theodore Heise" wrote in message
On Sun, 08 Jan 2017 17:01:01 -0800,
Jeff Liebermann wrote:
On Sun, 08 Jan 2017 16:31:15 -0800, Jeff Liebermann


Yet another untested idea...

Use an induction heater on the steel cup. [1]
You'll need various size coils for different bolts, cups, seat
etc. There are induction heater kits on eBay:

The steel cup gets hot and not so much the rest of the bicycle,
including the aluminum bottom bracket which sucks away much of
heat. However, you can get the steel hot enough to melt the
so please use an IR thermometer to keep the temperatures down.
Aluminum melts at 660C.


Is there a problem?

An electric heat gun is safer than a blowtorch - but I think you
to be a bit careful.

The heavy duty paint strippers aren't too bad, but some heat guns are
designed for lighting solid fuel cooking ranges.

The problem with external heat generators is that the heat affected
zone is rather large and will surely creep into undesirable areas,

A bigger problem is heating too small an area and causing the metal to

I'm sure that you've distorted many bottom brackets with a hair dryer.

and those really big curlers under a plastic cap...

With a burnt down lucky strike hanging off your lower lip.

Do you speak from experience?

Only in Tom Waits tunes.


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