Building a Great Lakes Sport 2T Sport Trainer

Great Lakes 2T1A-VR I-ESON
"the Outatime Flyer"

December 26th - 2007

With the English wheel on the stand and ready for use, we're finally back for a session on the metal shapingof the engine cowling. I've thrown away the 6082 panel; after having planished it with the wheel to planish out the mallet's bumps, I have overstreched the panel and added too much crown on it, so we went the opposite way for the final result.
Nonetheless, the shrinkage made on the edges with the hand srhrinker left the jaw's marrs on the metal which soon developed into cracks...
I then tried doing the panel in one piece with a softer alloy, 1050 H24 temper (half-hard). Unfortunately I don't have access to popular 3003 H14 here in Italy, but this 1050 H24 is similar and at least it can fit a skill test.

Unfortunately again, I only have a 1,5mm thick panel of this alloy in my workshop, so what I have gained in alloys softness I have lost with its thickness.

Panel is crowned enough but uneven

too much bumping at the middle

he flat T bar shows the uneven crown and panel's depressionst

too bad... hours and hours to get into this?!?

Finally, I faced one of the metalshaping rule: it's quite simple and fast to give to the panel the rough shape of the piece, but then is hours and hours of fine tuning, three steps forward and two backward... I finished with the panel shown in the pictures; which is "almost" sat on the buck, buck with an uneven crown everywhere (you can see it with the ruler) and I'm afraid to move it because any single hammering moves the panel to an unexpected result...

BTW, I'm not going to use this panel. It's actually too thick (and heavy) for this purpose, and not the best alloy for an engone cowl (with plenty of vibrations..)
I've recently joined the metalmeet.com community and hope to have some suggestions on how to proceed with it.
In the meanwhile, it will be testing, testing, and testing, till having enough skill and craftmanship to do it.

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