Thread: Soft Top
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Old 04-25-2011, 02:54 PM
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07cob 07cob is offline
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Default Softening Aluminium

Quote:
Originally Posted by Outwest34au View Post
For those that missed it here is a good article on bending channel with view to making window frames. Home-made Side Curtains for Lemans Top – “How To”.
Great tips in this write up. The Lotus site quoted (LocostUSA.com • View topic - Trouble Bending Aluminum for Windshield. Help) is where I got the idea for the jig.

The tip about using a Sharpie as a temperature indicator for annealing is also a good one.

I used soap for this. Rub the soap on the top three faces of the channel the heat from below. I used a LPG torch. The soap will turn brown then black. Afther that the aluminium will start to melt - not good!! Same as the sharpie method - stop heating as the soap goes black. This is the discoloration on the channel that can be seen in the photo above.

Colour chaning crayons can also be used if a more exact temperature is required.

The only downside to this is that unlike other metals, there is apparently no way to re harden the aluminium. It will work harden as aluminium does, but otherwise it will remain *soft*. Whether this is a problem will depend on the application. Probably not much good for an alternator bracket but fine for a cover panel.

Cheers

Geof
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