This is all true, but realize that you are using an example without money in the equation. When you add money then the act of saving allows investment for others to be available in the first place. And it doesn’t require a loan, this is what producing extra resources and thus lowering their price will naturally do. 

- If Bob doesn’t know what to invest in, he can produce and save money, and this gives the societal surplus of the same amount for Tim to make his fishing net. the same thing happens with the capital, him loaning it is merely for him to think he know exactly *what* to invest in.