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 BIKE IN THE TRUNK
Before you engage in the construction of microvesicle, I've been drawing various versions of its layout, trying on paper for all possible errors and miscalculations, which can only occur...
“…The outcome of the war could be very different”
In 1848 started the Danish-German war. The Germans, of the fleet which virtually did not exist, had nothing to oppose to the Danish ships, which blockaded the German coast. Then the...