Thin-walled tube of soft metal when you try to bend often creased. To avoid this, they are usually pre-stuffed with sand.
With the same purpose, you can use another method: navit on the future site of bend copper or aluminum wire – turns will not allow the tube to wrinkle at the bend.
The same result can be achieved using a suitable inner diameter of the spring.
Recommend to read
THE DYNAMICS OF THE RESONANCE EXHAUST PIPES
The use of the resonance of the exhaust pipes on the engine all model classes allows us to dramatically improve athletic performance competitions. However, the geometrical parameters of...
SAILING ALL YEAR ROUND
Perhaps this design will not leave indifferent any fan of Windsurfing. Still, is it not tempting to make a sailing Board, you can practice your favorite sport almost all year round!...