Back in 1960, U.S. Army Captain Bertrand Brinley published the Rocket Manual for Amateurs, one of the greatest DIY books ever written. Its cover price reads 75 cents. Buying a copy today in a used bookstore will set you back about $200. But it’s that good. (I know, I have it.)
There is a considerable amount of information on rocket motor making in RMFA. Now, back in the 50s and 60s, making rocket motors was a fashionable pastime, and there were lots of clubs and societies that would goof around making rocket engines.
But like any high energy hobby, things could and would go wrong and people got hurt. Rocket engines had a nasty habit of blowing up in the maker's face and causing injury. There is a part of the process where the propellant is rammed into a tube and that's pretty dangerous. (I personally know of a couple people who hurt themselves this way.)
So, the activity changed, led by Estes rocket company, people were encouraged to buy commercial rocket motors instead of rolling their own.
That is indeed much safer. But i think you lose something when you give up the core part of the activity. The Rocket Manual for Amateurs has the info needed to make several different types of rockets and rocket engines. I'm thinking about making some. I'll let you know.
