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.
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SUPPORT-UNIVERSAL
If you saw a Board, as shown in the picture, you get four blanks to build universal support for any rack — for example, the hanger or Christmas tree. Assembly can be done with nails or screws.