Metal forming Q

[redrider]

One of the muffler hangers is bent slightly. Not the pillion footrest hanger. It is aluminium. Should  I heat it before bending back to original profile and if so, quench afterwards. V11 café sport. (I re-installed the CF oval no name cans today)

[fotoguzzi]

I'm no metallurgist but I'd say NO.. isn't quenching for steel?  just try bending it when cool.?

[LowRyter]

does it look bad enough where feel compelled to do it?

The muffler must be OK since you didn't say it inhibited riding it. 

[Chuck in Indiana]

No, just cold bend it back.

[redrider]

Thanks for the replies. I ask because in my archives is a remedy for bent Norton Commando bits. The trick is to heat to cherry red in the area of the bend mend. Compelled? Not until someone walks up and saayzzz "Your mufflers are not aligned properly!"

[oldbike54]

 Hey , you're mufflers aren't aligned properly   

 Dusty

[Sasquatch Jim]

  Change the muffler bearings while you have it apart. 

[n3303j]

Thanks for the replies. I ask because in my archives is a remedy for bent Norton Commando bits. The trick is to heat to cherry red in the area of the bend mend. Compelled? Not until someone walks up and saayzzz "Your mufflers are not aligned properly!"

Cherry red aluminum forms a puddle on your work bench.
Cherry red steel will bend with little effort.
Heating to cherry red and quenching will harden some tool steels.
Aluminum sometimes hardens by repeated working and can be annealed with a heat cycle.
Other aluminum is tempered to produce a material that has more resistance to deforming.
Guess you get to experiment.
If I were making mechanical brackets I'd use a tempered aluminum. I'd assume others did the same. Straighten slowly and with care. You probably will be successful. You might significantly weaken the bracket.

[fotoguzzi]

  Norton 

= Steal !

[n3303j]

= Steal !

......only if you wish to be arrested!

[fotoguzzi]

......only if you wish to be arrested!

good catch.. Steel=Norton

[organfixsing]

My understanding of annealing aluminium is to heat and let slowly cool. The biggest problem is that if you heat too much it will just form a puddle on your workbench. A trick I have read, but not tried, is to rub soap (bath soap is OK) on the part and heat. When the soap melts? and goes clear, remove the heat and let cool. Whether this applies to aluminium alloys I know not. I would be testing on a scrap bit first.
My tuppence.
Cheers
Beian http://wildguzzi.com/forum/Smileys/default/grin.gif

[Chuck in Indiana]

Annealing sheet aluminum.
Turn your ox acetylene torch on acetylene only and make the piece black with carbon. Turn on the oxygen into a neutral flame and *very* carefully burn the carbon off. Quench in water.

[Kiwi_Roy]

In our club we have a guy who does fabulous work with Aluminum. He told me he uses just plain toilet soap, rubs it all over one side then heats over a burner until the soap goes black then either quenches it or simply allows it to cool, the flame method is too dirty he reckons.

[redrider]

Well there ya go, Dusty. Always startin' trouble.

Actually, I have removed the oval cans and reinstalled the MIVV ones. The loss of torque was not acceptable. I did remove the downturned "spout" on the dB killer. This piece was to the inside when installed. What I got in return is low and mid range grunt, STRONG pull to the rev limiter and more bass. Not quite as low as the others but close enough. And they are aligned properly. (insert Bill the Cat raspberry thppptt emoticon)

[Petrus Rocks]

Don't need to quench the aluminum.  The soap trick or the acetylene soot trick works well.  When you bend aluminum you work harden it.  Without heating it you get to bend it once.  Anyone remember trying to straighten aluminum dirt bike levers and have them break?  heat it up first.  the aluminum will turn  kind of a straw color when it is annealed.  I do it all the time when I'm forming sheet aluminum or bending brackets.

[racasey]

Blackening the aluminum with acetylene is effective, but rather messy as stands of oily soot float around the shop coating everything, including you.  I have had great success with a far cleaner and quicker method.  Simply take a common Sharpie black marking pen and make squiggly lines on the portion you are going to anneal.  Heat till the lines vanish, allow a few minutes to air cool and hammer to your heart's delight.

Depending on the complexity of the bends, you may need to anneal the part several more times. 





This lid was formed over a piece of common particle board with a 3/8 radius edge.  I suspect I annealed the edges of this 0.080" piece of 3003 aluminum 6 or 7 times.  The center was left 'as rolled' to make the lid more durable.



Ciao,
Dick

[Chuck in Indiana]

Sharpie. I'll be danged. What will you young whippersnappers come up with next? Sharpies hadn't been invented when I learned to anneal aluminum.