Tubes with 13 or 12 mm Ø are bent around a 23.5 mm radius
Tubes with 16 mm Ø are bent around a 22 mm radius
Do not bend over an angle of 180°, so that you can still remove the tube when it has cooled.
All bending mandrels and stoppers are designed for tube diameters of 12 or 13 mm and 16 mm. The necessary guidance is always aligned downwards.