well actually its pretty old, I built it when I was 14 or something, completely from scratch. But it didnt work that well, wouldnt really accelerate properly, flamed out easily, and had severe compressor stalls when the throttle was above ~25% or so. I couldnt figure out what was wrong with it because I didnt know anything back then, so I just got frustrated with it and left it alone.
Soon thereafter, in my dads opinion, it became "just another one of bens pieces of crap taking up space in my garage", so I put it down in the basement where it sat in the corner with xmas ornaments piled on top of it for a couple years.
A couple days ago I was bored and for whatever reason decided I wanted to mess around with it again. So I dragged it (300 someodd pounds) up the stairs with some complicated sketchy winch setup I rigged up in about 2 minutes. I threw it in the front end loader on the tractor and brought it over to our new shop. Took it all apart, redid a couple of my initial stupid design features, but the main thing that needed redesigning was the combustion chamber, diffuser, injector/igniter, and flame tube liner.
Did some quick mathematical calculations, some educated guesses here and there, and made a new setup. Put it all back together and what'dya know, it works great.
it sounds cool too...well, like a real jet aircraft engine. Its 100% as loud as a full scale jet engine too, trust me.
I ran it a bunch and then the oil seals in the turbo started to go bad. Of course the times when I had it running great for a while (10 minutes or so, its really thirsty), I never videoed it. When the seals started getting really bad I finally got a decent video of it running for about 30 seconds before I had to shut it down due to oil streaming out the exhaust pipe.
Like the early mechanical jet engines of the 1940's and 1950's (way before FADEC and electronic engine controls), it is very sensitive to operate and you really need to know what you are doing, otherwise it can run away and will keep spooling faster and faster until the bearings or turbine wheels let go. Starting it up is a very precise process too...Im a pilot so I have a decent idea how to go about starting a jet turbine engine, but it was still a little scary the first time I started it. You have to do about 10 things at once all while watching 6 gauges. Id like to setup an air starter or even an electric starter because using a leaf blower is kind of ghetto.
I start it on propane, and then switch over to jet fuel. (Jet-A is more or less a mixture of kerosene and diesel)
Before the seals went bad, it ran very well. TIT (turbine inlet temp, ha ha yeah, funny isnt it) runs around 1250* and TOT (turbine outlet temp) runs around 1000-1050*. N1 gets up to around 30psi at 75% throttle and N2 runs around 40psi. Oil pressure runs about 40psi and oil temp runs around 100*. So overall, it is running quite well, in my own opinion.
Ill post more pics, but heres a video of it running with blown seals. Otherwise I would have run it up to full throttle and kept it going for a few minutes...
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Ben
Soon thereafter, in my dads opinion, it became "just another one of bens pieces of crap taking up space in my garage", so I put it down in the basement where it sat in the corner with xmas ornaments piled on top of it for a couple years.
A couple days ago I was bored and for whatever reason decided I wanted to mess around with it again. So I dragged it (300 someodd pounds) up the stairs with some complicated sketchy winch setup I rigged up in about 2 minutes. I threw it in the front end loader on the tractor and brought it over to our new shop. Took it all apart, redid a couple of my initial stupid design features, but the main thing that needed redesigning was the combustion chamber, diffuser, injector/igniter, and flame tube liner.
Did some quick mathematical calculations, some educated guesses here and there, and made a new setup. Put it all back together and what'dya know, it works great.
it sounds cool too...well, like a real jet aircraft engine. Its 100% as loud as a full scale jet engine too, trust me.
I ran it a bunch and then the oil seals in the turbo started to go bad. Of course the times when I had it running great for a while (10 minutes or so, its really thirsty), I never videoed it. When the seals started getting really bad I finally got a decent video of it running for about 30 seconds before I had to shut it down due to oil streaming out the exhaust pipe.
Like the early mechanical jet engines of the 1940's and 1950's (way before FADEC and electronic engine controls), it is very sensitive to operate and you really need to know what you are doing, otherwise it can run away and will keep spooling faster and faster until the bearings or turbine wheels let go. Starting it up is a very precise process too...Im a pilot so I have a decent idea how to go about starting a jet turbine engine, but it was still a little scary the first time I started it. You have to do about 10 things at once all while watching 6 gauges. Id like to setup an air starter or even an electric starter because using a leaf blower is kind of ghetto.
I start it on propane, and then switch over to jet fuel. (Jet-A is more or less a mixture of kerosene and diesel)
Before the seals went bad, it ran very well. TIT (turbine inlet temp, ha ha yeah, funny isnt it) runs around 1250* and TOT (turbine outlet temp) runs around 1000-1050*. N1 gets up to around 30psi at 75% throttle and N2 runs around 40psi. Oil pressure runs about 40psi and oil temp runs around 100*. So overall, it is running quite well, in my own opinion.
Ill post more pics, but heres a video of it running with blown seals. Otherwise I would have run it up to full throttle and kept it going for a few minutes...
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Ben
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