Machining Motor Hardware

Terry "The P'rfesser" McCreary's book, Experimental Composite Rocketry contains detailed plans for machining Kosdon-like casings and nozzles. The P'rfesser also tells you how to make a digital test stand. Buy the book here:

Word to the wise though, if you don't already own and know how to use a metal lathe, it will probably be cheaper to buy a set of casings. There are many such vendors online.

On the other hand, if you DO need to buy a metal lathe, I can recommend the Homier 7x10. Remember though that the machine purchase is really just the tip of a real big iceberg. You will easily spend more than the purchase price of the lathe on bits, tool posts, collets, cutoff tools, boring bars, etc, etc, etc. Not to mention cost of lathe stock.

Whichever route you go, DO get The P'rfesser's book and read it cover to cover.

Several times.

It is entertaining as well as informative.

Best of Luck!

Steve Decker Square-jawed Chief Engineer of the Patternmaking Division

fyi,

Loki Research has the best price I've seen for this book

]

- iz

Thanks for the information. I do have McCreary's book, although I have not yet built my on motors. I already have a metal lathe, a MicroLux 7x14, so that is not a new expense.

I have been doing ok renting motor hardware. It allows me to choose from the full line of motors instead of the ones for which I own the hardware. But it would be nice if I could at least try to machine my own Pro54 hardware, for example. If I owned one, I could make the measurements to try to machine it (but then I would not need to make my own :).

Since EMRR has detailed plans of many kits I thought it only logical that EMRR also keep a repository of the exact dimensions, thread sizes, placement, etc. for all the known motor hardware. Can anyone help with this?

Thanks,

Ferrell Wheeler

check out microhybrids. plans at

for $10 i think.

If I had a lathe i'd build it myself as they are not optimized for performance.

Mike,

I noticed at your website that you are experimenting with small aerospike motor designs. Since you are building aerospike nozzles for other EX'ers, would you be willing to give or sell your design for making the aerospike nozzles themselves instead of just selling them premade? I would be very interested in someday attempting to make such a nozzle (you always learn more by making things yourself and it gives one more experimentation options). The pictures you have of test firing these aerospike motors look great!

Thanks,

Ferrell

BTW, my wife certified level 1 with the Binder Design "Spike" kit. She painted it pink with flames growing from the bottom morphing into roses. :)

Tater,

Thanks for the tip. The microhybrid plans look great. That is now definitely on my list to try.

I still think that the rocketry community would benefit from having detailed designs available for the various types of reuseable motor hardware.

Ferrell

Men paint rockets. Women decorate them. Don't believe me? Ask.

Jerry

For amateur use, the snap ring style hardware can't be beat for versatility, cost and ease of machining.

Mike Fisher

nice price, Mike!

BTW, the cover on mine has some grain cross sections and thrust curves on the front. Not having done my research, I overpaid for it by over $10 at Skylighter

I hadn't imagined such a variation in price at the time. Live and learn

I really don't feel so bad, IMO I'm happy to have helped a rocket vendor, but we should have access to the best price, which I later discovered

- iz

Yeah, Terry has designed a new cover since my web photo was taken....same content...neato new cover. All of the new copies come that way. Now if I could just get him to hand sign every copy that I sell. :)

Terry sent me a new Experimental Rocketry Group T-shirt with my last shipment. I'm thinking about stocking those.

Mike Fisher