Working with sheet metal
Round bends (tubes, rounds, semi-circles, etc.)
If you want to bend your sheet into a round object, then round timber, available in different diameters is well-suited for this purpose. Screw the sheet, together with its protective foil, onto the round timber. Ensure that there is a precise right-angle to the longitudinal axis of the round timber!
So that the sheet is bent exactly parallel, it must not slip under any circumstances during the powerful bending process. For this purpose you must ensure that it is firmly clamped on the edge of the workbench (e.g. with alfer®-Multi-clamps or other vises).
Then turn the round timber uniformly towards you and apply a lot of force, at the same time you push the wood away from you and keep it under high pressure.
Pay strict attention to the straight course of the round timber, so that the round body formed by the sheet is not spiral shaped. This straight course is controlled by ensuring that the rolled sheet edge is always precisely aligned with the edge of the sheet still lying flat.
Due to the spring recoil of the sheet you must rotate it about 1.5 times. After unscrewing the round timber the bent sheet will go back to an approx. 30% larger diameter.
Now you can push the sheet so far into itself until your precisely desired diameter is reached. Afterwards fix this diameter by riveting, soldering, bonding, or welding.