Robert’s Rocket Project has been going on for a long time. It has been around so long that you can go all the way back to posts from 2001, where he talks about getting his first digital camera! The site is dedicated to his pursuit of liquid fueled rocket engine building. It’s a great project log and he has finally come to the point where he will be testing his first flight vehicle soon.
His latest project is a 250lbf regeneratively cooled engine. It uses kerosene as the fuel, and liquid oxygen as the oxidizer. The neat thing is he utilizes the temperature change of the liquid oxygen expanding to cool the chamber and nozzle before being burned. This allows for a very efficient and powerful combustion of the fuel. He has some videos of testing it on his site, we just wonder why he doesn’t host them on YouTube or something…
Anyhow, there’s more than enough info on his site to try and recreate some of his experiments, but perhaps you should start here instead: How to Design, Build and Test Small Liquid-Fuel Rocket Engines.
[Thanks Ray!]
very nice unistrut construction
the F1 engines in the atlas rockets flowed the liquid lines around the nozzel to keep it cool as well… and if I remember correctly there are some details here http://arstechnica.com/science/2013/04/how-nasa-brought-the-monstrous-f-1-moon-rocket-back-to-life/
The newer designs cut costs by removing the cooling lings from the nozzle which makes it a bit lighter as wel… there were some trade offs mentioned in the article I read.
How is a “Watermelon air boat” related to a “DIY 250 lb thrust Liquid Oxygen/Kerosene Rocket”?!?!?!
Oh, come on – watermelons? kerosene? You don’t see the connection?
Keyword “thrust” maybe?
Metaphor powered science.
yes thrust may be the common keyword but other than that nothing shared.
also there may be some legal issues with rockets especially in a world of terrorism.
If you’re paranoid enough, there are legal issues with *everything* (even watermelons) in a world where terrorism is used as an all-purpose reason to aggressively enforce laws.
Seriously, we need to take back the ability to experiment with potentially dangerous things. Anything, even a pressure cooker, can be used as a terrorist weapon, but that doesn’t mean anyone (even a long-haired middle-eastern type guy) buying a pressure cooker is a terrorist. We (I’m in my 50s) made gunpowder as kids. The recipe was in every encyclopedia. We set off smoke bombs, launched tin cans into the air with firecrackers, and split a toilet bowl in half with a cherry bomb. But none of us ever managed to hurt anyone. We learned how to replace a toilet, and we had a sh!tload of fun!
Sorry, but this is a sore point for me. It’s time to inject a little skepticism and common sense into the world, otherwise the terrorists have already won.
Although you must admit that we no longer live in a world where a kid can just innocently walk into a school carrying a .22 rifle because he wants to go plinking afterwards.
True. Although, you could probably still get away with that in some of the more remote areas of the western US…I think it’s all about community expectations.
My experience was in a suburb of Boston. We all managed to live through the experience, and I think we are smarter for it. I’m annoyed at this overly paranoid mindset, which seems to be stoked by the media and the law enforcement community. Everything’s a “potential terrorist incident” until proven otherwise. Kids who make CO2 bombs out of soda bottles are being charged under the PATRIOT act. Common sense (and memory of what the arresting officer probably did as a kid) seems to have taken a permanent vacation…or maybe it’s been locked up in Guantanamo?
One hates to think what would have happened to Goddard with his liquid fueled rockets outside of Worcester…
Common sense seems to have become an oxymoron.
I liked the way one of my professors put it, probably stolen: “Think of how stupid the average person is. Now think: half of the population is stupider than that.”
Wyoming Catholic College allows students to have firearms on campus, but they are not allowed to have cell phones in class.
I think it’s more important to learn to differentiate between “the feds *could* think I’m a terrorist” and “the feds *will* think I’m a terrorist.” It’s not like people are getting investigated by the FBI for buying pressure cookers.
To expand on that, a huge part of the reason widespread government surveillance is a bad thing isn’t just because it invades privacy, but because it has a “chilling effect.” It makes people afraid to try new things or express themselves, even if the fear is out of proportion with the risk. This is the exact same quirk of psychology that terrorism exploits. The only thing that can be done other than elect ethical, responsible officials (lol) is to be carefully rational when assessing risk.
The feds investigate a lot of mundane crap. They commonly run investigations and maintain open files on citizens who have already been found to be no threat… simply because they do the same things they were found to be no threat for doing in the past. A photographer recently complained about being repeatedly contacted by feds because he travels and photographs landmarks and industrial facilities. This is years after first being investigated and found to be no threat.
People can change.
That is the asseveration of the textile industry, any way…
Watermelons again, it has to have four tail fins for sure.
” we just wonder why he doesn’t host them on YouTube or something…”
Because by uploading stuff to youtube, you effectively give up on your copyright to them. Check the terms of service.
Also, YouTube sucks. :-)
Actually, the fuel (kerosene) is used as the coolant not the oxidizer (LOX).
Okay, so what is the weight of this 250 pound thrust engine? Is it capable of liftoff? Is it capable of liftoff with any reasonable amount of fuel?
I don’t think this particular engine is destined for flight. I think it’s just R&D
This engine is intended to fly. It is not a minimum weight design but it only weighs a few pounds so it should work fine. The next challenge is to design the airframe, tanks, recovery system, etc. for the flight vehicle.
I have a manned aeroplane/rocket project where this engine could be used to test in a 1/6 scale model of a real Mars going craft in the future.
I had the full text of “HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUEL ROCKET ENGINES” printed out back in the late 90’s, with that guys stuff insipring me of course. I soooo wanted a good lathe back then so I could build one of these liquid fueled engines. I also had a lot of stuff on building jet engines out of turbo chargers. Now I have no time or money for such fun!
why don’t you check out the gingery method. i have all the books in pdf files i can send you if you want, OR you can get them from bookos for free, you just can only get seven books a day. gustr817@gmail.com if you want the books. you build a foundry and cast the parts for your lathe yourself. granted, you need an electric motor, but… find a broken electric lawn mower for 20 bucks at goodwill, and tear it apart and fix the motor… attach a dimmer switch, and that’s your innaccurate speed control for your ghetto homemade lathe that turns metal and builds you your own rocket. and drill press and milling machine etc. etc… david gingery is a fucking god hahaha. i highly reccomend reading his books even if you aren’t making the tools. helpful info for sure.
He’s not the only one building his own liquid fuelled rocket engine, Copenhagen Suborbitals have built an even bigger one (but they have a bigger team):
http://www.youtube.com/watch?v=bqASqda0ylc
I need one of those ! Where can I get one ?