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Bending steering arms
speedyxjs - 4/1/11 at 08:40 PM

I understand that cutting nd rewelding the steering arms on the hubs is an IVA no no so i was thinking wether it would be ok if i heated and bent them?

britishtrident - 4/1/11 at 09:00 PM

Minefield, before you start you have to be 100% sure what type of ferrous material you are dealing with, assuming it is a forged steel then you need a lot of localised heat you must heat through to the core and especially concentrate on the compression side of the bend. Don't try and bend too much at one heating but work quickly, quench after final heating then apply milder heat and allow to naturally cool.

After that make 100% sure you get the part crack tested.

Personally I wouldn't do it.

daviep - 4/1/11 at 09:12 PM

Not done it myself but I believe it was common practice for the stock car racers to bend the steering arms on cortina uprights. Would suggest to me that it is possible.

I understand that on a racing track the consequences of a failure are different to it happening on a public road with on coming traffic.

Davie

gavin174 - 4/1/11 at 09:34 PM

would be mot failure..

so i would imagine would be iva fail...

when i worked in garages about ten years ago we were stopped heating track rod ends with oxy when doing trackings as it could cause mot failure



[Edited on 4/1/11 by gavin174]

britishtrident - 4/1/11 at 10:52 PM

quote:
Originally posted by gavin174
would be mot failure..

so i would imagine would be iva fail...

when i worked in garages about ten years ago we were stopped heating track rod ends with oxy when doing trackings as it could cause mot failure



[Edited on 4/1/11 by gavin174]



Different situation, a track rod is as load case called by structural and mechanical a slender strut in compression with pinned ends.
With a slender strut even a slight bend reduces the load needed to cause the strut to buckle by a very large margin, it is nothing to do with effect heating the material purely to do do with the physical shape, this backed up by the maths worked about 250 years by clever geezer called Leonhard Euler who came from a whole family of clever geezers.









Bending a steering arm poses different dangers, the steering arm is loaded in pure bending, the bending moment isn't altered much by bending the steering arm the heating bending and cooling the steering arm introduces the possibilities of fracture due to heat treatment. or fracture mechanics problems.
When a carbon steel is heated and cooled it introduces the real risk the sections of the material become hard and brittle, also if bent when too cold it introduces the danger of creating cracks on the tension side of the bend.

[Edited on 4/1/11 by britishtrident]

speedyxjs - 5/1/11 at 07:14 AM

Ok cheers guys, worth a shot

NS Dev - 6/1/11 at 09:05 AM

As long as its (in very simple terms) a "good" forged steel, then you should be ok. Cortina I would do, sierra ones not.