jwhartley
Plastic
- Joined
- Oct 20, 2004
- Location
- Minnesota, USA
As has been mentioned, musical instrument have many bends that are similar, conceptually, to what the OP is trying do do.
The best example I can think of is the bell-tail on a trumpet. The tubing is ~0.6" in diameter and the 180deg. bend has a diameter of ~4-5". The wall is something like 0.030".
You can see an example of making the bend here: YouTube
See time: 5:10
This is the Yamaha procedure. You can see that they are using Cerrobend or some similar low-temp alloy to make the bend. I have seen other manufacturers use water, then freezing to support the tubing for the bend. They add a little detergent to the water to make the ice weaker and less brittle. The water is a lot easier to clean up than the Cerrobend.
My experience with instrument tubing suggest that annealing the tubing beforehand would be a good path to success.
When making the bends, you still can get some wrinkling. These are then hammered out to smooth up the bend.
-Jess
The best example I can think of is the bell-tail on a trumpet. The tubing is ~0.6" in diameter and the 180deg. bend has a diameter of ~4-5". The wall is something like 0.030".
You can see an example of making the bend here: YouTube
See time: 5:10
This is the Yamaha procedure. You can see that they are using Cerrobend or some similar low-temp alloy to make the bend. I have seen other manufacturers use water, then freezing to support the tubing for the bend. They add a little detergent to the water to make the ice weaker and less brittle. The water is a lot easier to clean up than the Cerrobend.
My experience with instrument tubing suggest that annealing the tubing beforehand would be a good path to success.
When making the bends, you still can get some wrinkling. These are then hammered out to smooth up the bend.
-Jess