After spending some more time on this project, some more constraints have arisen that I did not see in the beginning.
My top five constraints are:
The pitch – getting the diameter and lengths of the tubes right so that the chimes actually sound good. There are some equations for this but it may take some trial and error which could cost a lot of time.
Time – As mentioned above, depending on how everything goes I may be cutting it close on time, we’ll see.
Machine shop availability – This is an unknown that factors into the time constraint, if I’m lucky I could probably do all of my machining in a few days, if I’m unlucky it might take a few weeks.
Balance – Getting the balance of the system right is going to be a key part to making this look good, function, and last.
Precision – Getting the cuts and holes right on the first go is very important to keep the costs reasonable. Since the aluminum bars will be relatively expensive, it is important not to have to re-buy any. I mentioned getting the diameters and lengths right in the first constraint; for the length part it’s important to cut long, not short and go from there.