New JetJoe J-Junior 4lbs turbine
#526
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RE: New JetJoe J-Junior 4lbs turbine
i feel a mesh would do fine cosmetically. In terms of providing fine particles protection,it is futile. Leaving it open would provide better cooling. I did not cut open the air intake on the sides of the vortex for fear of particles ingestion. So i depends on this opening for air.
#528
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RE: New JetJoe J-Junior 4lbs turbine
So today I went to the field to try my JUNIOR. The first flight went well. On the second one the JUNIOR flameout at takeoff. After cooling I tried to start and when I reach 60.000 RPM, I have HIGH TEMP on the display also I felt that something was vibrating. In the visual examination I found the turbine nut like you can see on the photo.
#529
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RE: New JetJoe J-Junior 4lbs turbine
The Jetjoe company is not known for their careful selection of materials. I think your nut was machined from a piece of cheese. looks like you need to send it back to china.
Jason
Jason
#531
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RE: New JetJoe J-Junior 4lbs turbine
ORIGINAL: jason
The Jetjoe company is not known for their careful selection of materials. I think your nut was machined from a piece of cheese. looks like you need to send it back to china.
Jason
The Jetjoe company is not known for their careful selection of materials. I think your nut was machined from a piece of cheese. looks like you need to send it back to china.
Jason
#532
Senior Member
RE: New JetJoe J-Junior 4lbs turbine
I feel the nut can easily be replaced locally. Sending it back to china, u might get the same quality nut be installed,and u are back to square one.
#541
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RE: New JetJoe J-Junior 4lbs turbine
That is one scary picture. It is testament to the forces these little jets generate at max rpm.
Is it a heat related failure? Or has the material just had it's elastic limit exceeded?
This has hit my curiosity button. I want to know why it has failed like that. [ And can only have been a few seconds at most from total failure. ]
In my time as an engineer I have seen a number of stretched bolts but never a nut.
Is it a heat related failure? Or has the material just had it's elastic limit exceeded?
This has hit my curiosity button. I want to know why it has failed like that. [ And can only have been a few seconds at most from total failure. ]
In my time as an engineer I have seen a number of stretched bolts but never a nut.
#542
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RE: New JetJoe J-Junior 4lbs turbine
ORIGINAL: j.duncker
That is one scary picture. It is testament to the forces these little jets generate at max rpm.
Is it a heat related failure? Or has the material just had it's elastic limit exceeded?
This has hit my curiosity button. I want to know why it has failed like that. [ And can only have been a few seconds at most from total failure. ]
In my time as an engineer I have seen a number of stretched bolts but never a nut.
That is one scary picture. It is testament to the forces these little jets generate at max rpm.
Is it a heat related failure? Or has the material just had it's elastic limit exceeded?
This has hit my curiosity button. I want to know why it has failed like that. [ And can only have been a few seconds at most from total failure. ]
In my time as an engineer I have seen a number of stretched bolts but never a nut.
The only way this could have happened is with a very high heat and a very cheap steel for the bolt. (I really hope they didn't make it from alu)
This should be a warning to other JJ owners. Poor materials will bite you where you least expect it. If that wheel would have come loose the result could have been horrific. The energy pent up in there is amazing. It could have easily gone through a car door let alone a hand or foot.
#544
RE: New JetJoe J-Junior 4lbs turbine
Have you guys seen this Fly Fly MB339 with the kolibri.
http://www.youtube.com/watch?v=ZD-AwbzfzaM
I bet the JJJ will fly it about the same way.
Would be nice if you could use all the FlyFly airframes for these smalle jets.
http://www.youtube.com/watch?v=ZD-AwbzfzaM
I bet the JJJ will fly it about the same way.
Would be nice if you could use all the FlyFly airframes for these smalle jets.
#550
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RE: New JetJoe J-Junior 4lbs turbine
My junior is back from china.
Joe have change the compressor, the shaft, the nuts, the bearing and the exhaust cone.
I will test flight it on sunday.
Joe have change the compressor, the shaft, the nuts, the bearing and the exhaust cone.
I will test flight it on sunday.