Originally Posted by wret
I've seen where others have had trouble kinking or crushing the tubing when making a sharp bend, even when filling the tube with sand. My solution was to shove a tight fitting hardwood dowel into the tube at the site of the bend. Worked like a charm.
Another good way is to cap the ends, fill it with water, and freeze it.
Once it's frozen, it will bend without kinking much better.
The problem with sand is you have to keep it sealed to work. Once water freezes, capping is no longer needed as the ice holds itself in, unlike sand which will move under pressure.
Even better, fill it with sand, then wet and freeze it.
If more is better, then too much is just enough.
If you can't afford it, build it yourself.