Hi Everyone;
I am looking into building a Murphy Renegade biplane. It's made largely of aluminum tubing riveted together. I'm not completely familiar with the whole structure, as I don't have the plans yet, but I plan to buy some of the more challenging parts, and build what I can.
Some of the more challenging parts include a unique aluminum extrusion that slides over the fuselage longerons, and has two sets of flanges on it to allow other tubes to be riveted to it. Neat idea. I'd buy that extrusion, as well as a few other items, wing ribs, etc.
I also noticed lots of areas where aluminum tubes are bent fairly substantially and with a tight radius. I believe this is 6061-T6. Please see the first two pics, the rear landing gear strut, and another fuselage structure in the cockpit area.
I was always under the impression that 6061-T6 could not be bent like this. I suspect that wall thickness may play a factor in this bending work, and I wish I knew what the wall thickness was, but here comes my question. Can this sort of bending be done, reliably, in a home shop, without damaging the load-carrying ability of these parts (induced cracking)? One part seems to be round tubing, and the second is clearly square with some slightly visible kinks on the inside of the bend.
How would you do these bends in your shop? I assume heating is out of the question, as this presumably would soften the aluminum and destroy it's T6 properties, strength, etc.
Thanks, Tom.
I am looking into building a Murphy Renegade biplane. It's made largely of aluminum tubing riveted together. I'm not completely familiar with the whole structure, as I don't have the plans yet, but I plan to buy some of the more challenging parts, and build what I can.
Some of the more challenging parts include a unique aluminum extrusion that slides over the fuselage longerons, and has two sets of flanges on it to allow other tubes to be riveted to it. Neat idea. I'd buy that extrusion, as well as a few other items, wing ribs, etc.
I also noticed lots of areas where aluminum tubes are bent fairly substantially and with a tight radius. I believe this is 6061-T6. Please see the first two pics, the rear landing gear strut, and another fuselage structure in the cockpit area.
I was always under the impression that 6061-T6 could not be bent like this. I suspect that wall thickness may play a factor in this bending work, and I wish I knew what the wall thickness was, but here comes my question. Can this sort of bending be done, reliably, in a home shop, without damaging the load-carrying ability of these parts (induced cracking)? One part seems to be round tubing, and the second is clearly square with some slightly visible kinks on the inside of the bend.
How would you do these bends in your shop? I assume heating is out of the question, as this presumably would soften the aluminum and destroy it's T6 properties, strength, etc.
Thanks, Tom.