Silly, Foolish Ideas...
03-22-2013, 05:26 AM
#27
Thread Starter
RE: Silly, Foolish Ideas...
I have been thinking about reinstating my 20 powered ducted fan project for a while.
An update that I didn't post, after the problems with the fibreglass, I had major engine issues: the engine you saw in th previous pictures is in fact rather heavily reworked. The crank and sleeve are origional, but the crankcase is my own design. I had relied on a two piece setup for the cylinder to convert it to rear exhaust.. Held together with the other essential substance in the universe other than dark matter, that is, JB weld of course. And It had been working just fine, but then I found that when the engine was hot, and got slightly flooded, two pieces again. Not a happy situation. That + the fuselage issues = time to give it a rest for a while.
.....
After making some new bits and using a very fine thread and JB weld to hold it together. ( glue and screw for all you carpenters out there) I have what should be a functioning engine again, that i think will stay together this time. I have also had a year to think off and on about how I might make a plane light enough to fly, and low and behold, I found low density extruded polystyrene on sale here! The very material to shape a fuselage from. I have given up my idea of a glass fuse for now. I am just thinking of how I can put together a plane that weighs ~200gms or less total flying weight. I have some ideas, I will post pictures as I have them.
But next is the make or break testing of the engine, and DF unit, and see how much thrust there actually is.
S
An update that I didn't post, after the problems with the fibreglass, I had major engine issues: the engine you saw in th previous pictures is in fact rather heavily reworked. The crank and sleeve are origional, but the crankcase is my own design. I had relied on a two piece setup for the cylinder to convert it to rear exhaust.. Held together with the other essential substance in the universe other than dark matter, that is, JB weld of course. And It had been working just fine, but then I found that when the engine was hot, and got slightly flooded, two pieces again. Not a happy situation. That + the fuselage issues = time to give it a rest for a while.
.....
After making some new bits and using a very fine thread and JB weld to hold it together. ( glue and screw for all you carpenters out there) I have what should be a functioning engine again, that i think will stay together this time. I have also had a year to think off and on about how I might make a plane light enough to fly, and low and behold, I found low density extruded polystyrene on sale here! The very material to shape a fuselage from. I have given up my idea of a glass fuse for now. I am just thinking of how I can put together a plane that weighs ~200gms or less total flying weight. I have some ideas, I will post pictures as I have them.
But next is the make or break testing of the engine, and DF unit, and see how much thrust there actually is.
S
03-22-2013, 05:48 AM
#28
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RE: Silly, Foolish Ideas...
Great to hear of the update.
Have you tried out carbon fiber?
I know there are various companies selling carbon fibre starter and repair kits, it handles pretty similarly to fiber glass but should be lighter, stronger and more rigid.
I made a few bicycle parts with it and ithey turned out well, i used a foam core for forming and then when everything was set I melted to core out, it would be easy to put together
an incredibly stiff fuselage and wing from the stuff if you're willing to try it.
I might have a go at making a plne form it one day but right now I'm re discovering other things about the hobby and life in general.
Good luck to you and I'd lvoe to see pics and or a video of this little beast.
Ta
Indra
Have you tried out carbon fiber?
I know there are various companies selling carbon fibre starter and repair kits, it handles pretty similarly to fiber glass but should be lighter, stronger and more rigid.
I made a few bicycle parts with it and ithey turned out well, i used a foam core for forming and then when everything was set I melted to core out, it would be easy to put together
an incredibly stiff fuselage and wing from the stuff if you're willing to try it.
I might have a go at making a plne form it one day but right now I'm re discovering other things about the hobby and life in general.
Good luck to you and I'd lvoe to see pics and or a video of this little beast.
Ta
Indra
03-24-2013, 03:33 PM
#29
Thread Starter
RE: Silly, Foolish Ideas...
Nitro,
I was looking at how some guys making micro electric edf have moulded depron- if I could do that and then cover it with a very thin layer of glass I could end up with something very light and reasonably resilient.
The though of making moulds etc is a bit of a turn off though.
I ran the engine setup, and a very rough measure of thrust seems to indicate about 140gms without an intake lip.
I figure that's a good number to work from, as there will be losses when the thing is mounted in the plane, and gains from a better intake, so it should be about 140 gms thrust in the plane.
I was looking at how some guys making micro electric edf have moulded depron- if I could do that and then cover it with a very thin layer of glass I could end up with something very light and reasonably resilient.
The though of making moulds etc is a bit of a turn off though.
I ran the engine setup, and a very rough measure of thrust seems to indicate about 140gms without an intake lip.
I figure that's a good number to work from, as there will be losses when the thing is mounted in the plane, and gains from a better intake, so it should be about 140 gms thrust in the plane.
