Induction Heating as explained by Chat GPT

[Amir Avitzur]

Heat Distribution:

• Inside-Out Heating: The key feature of induction heating is that the heat is generated inside the object itself, rather than by an external heat source via heat conduction.
• As a result, induction heating tends to heat the interior of the workpiece first.

Induction heating, theoretically, looks like a good fit for bottom brackets with internal lugs.

Does anybody on the list use induction heating?

--

Amir Avitzur
R"G Israel

[John Thompson]

On 2/18/24 14:06, Amir Avitzur wrote:
> *Heat Distribution*:
>
> * *Inside-Out Heating*: The key feature of induction heating is that
> the heat is generated *inside the object itself*, rather than by an

> external heat source via heat conduction.

> * As a result, induction heating tends to heat the *interior* of the

> workpiece first.
>
>
> Induction heating, theoretically, looks like a good fit for bottom
> brackets with internal lugs.
>
> Does anybody on the list use induction heating?

Trek used induction heating with automatic feed of brass wire into the
joints in the mid-80s. It looked promising, although the lug shorelines
always seemed to need a little manual touch-up. Unfortunately, this
process came online at Trek right around the time steel frames were
falling out of fashion, in favor of aluminum and carbon fiber. One issue
that might preclude custom builders from adopting induction heating is
that the inducer blocks need to be carefully designed to ensure even
heating of the work. Different lug angles and such required different
inducer blocks. I left Trek before all the bugs got worked out of the
process, so I can't comment on how the process might have improved for Trek.

--

-John (JohnDT...@gmail.com)
Appleton, WI USA

[pa...@ellisbriggscycles.co.uk]

Induction heating if used would be most suitable for mass production, like the Trek example.  In mass production, the whole point is to bypass the need for skilled crafts people.  I just don't see how it could ever be relevant for handmade steel frames?  Brazing with a torch can be fast and efficient for those with the skills.

Paul Gibson

Ellis-Briggs

Shipley, Yorkshire, UK

https://www.ellisbriggscycles.co.uk

[Mark Bulgier]

John Thompson wrote:

Trek used induction heating with automatic feed of brass wire into the
joints in the mid-80s. It looked promising, although the lug shorelines
always seemed to need a little manual touch-up. Unfortunately, this
process came online at Trek right around the time steel frames were
falling out of fashion, in favor of aluminum and carbon fiber. One issue
that might preclude custom builders from adopting induction heating is
that the inducer blocks need to be carefully designed to ensure even
heating of the work. Different lug angles and such required different
inducer blocks. I left Trek before all the bugs got worked out of the
process, so I can't comment on how the process might have improved for Trek.

This is good intel, thanks!  

So did any induction-brazed frames make it to consumers, or was that just in-house testing? 

-Mark B

[M-gineering]

Gazelle had a complete induction brazing line for years, ofcourse it
went for scrap when the framebuilding went to aluminium and China

> PR05MB99168A4222D3D19904AB043BDC512%40SN7PR05MB9916.namprd05.prod.outlook.com?utm_medium=email&utm_source=footer>.

--
mvg

Marten Gerritsen



Gerritsen & Meijers, Ingenieurs
Framebuilding & Imports

Dorpsstraat 132
9605 PD Kiel Windeweer
Netherlands

Tel: +31 598 491865


www.m-gineering.nl