Yes - I have way too much time to think up this rubbish !! I should actually be sleeping - have ships moving during the night and I have to be around for it !
OK - Pipe-Dream ?
I bet someones already done it - so if you have a photo - then please upload for us to see it !!
Idea : Domestic plastic water-pipe .. that's the fuselage ... then flat plate wing and tail parts. Motor is mounted into the pipe ... battery / esc / servos onto the pipe where best and how best !
Fancy construction - no the simplest !
Anyone fancy it ?
I reckon a piece of 3/4 or 1" pipe ... maybe 2ft long. Flat plate wing maybe 2ft span... inserted through a slot in the pipe.
Tail parts are formed into a T shape and then slotted into rear of pipe with elevators / rudder accordingly.
Motor with X mount of ply / ? to fit to front. Wires run inside and then exit to ESC etc.
The Hot Tube, a 1960 vintage multi with the twin engines mounted back-to-back within the tube. Found on Outerzone. There is also one there called the Ballooney, a balloon powered tube jobbie with a triangular wing.
Now all I have to do is find a tube that matches a standard EDF ...
OK - lets explore the concept to extremes !!
We take a standard domestic plastic pipe. Doesn't really matter what diameter - but lets say a 2" job ... (50mm).
We have pipe clips that fit that and with flat screw face for wall ... well that face now provides the wing / tail fixing face. We can glue / screw the clip to the pipe .. A wing would need maybe 2 or 3 and tail 1 or 2 clips.
We could even fit U/C via clips if necessary ... but I would go for a hand launch.
Gear can be fixed to exterior of tube either side under the wing ... with small foam blocks to fair the air over them.
We could even devise different wings to swap on the basic 'power-tube' ... using the clips and a few screws to ply plates in the wings etc.
C'mon guys and gals ... how's about a bit of a laugh - see what we can come up with ?? Prop or EDF ...
I'm even thinking about a TWIN !!
What about a Styrofoam central profile fuselage .. then a plastic tube either side with EDF in .. wing on top etc. ... sort of Buccaneer style design ? Simple ...
For your "Pipe" dream, use thin walled drain "Pipe"....readily available here in the states in two sizes...3" O.D. and 4" O.D. Might be other sizes available but those two are easy to find and only about 8 bucks for a 10' length.... Then a few well thought out slits in the back of your tube, a little heat, some PVC cement, a compression band of some kind and you've got your efflux nozzle....
Duraplane had a great trainer that was made from a 2" pvc downspout tube that can be had from Home Depot for about $10/8' length. I am in the process of making a sudo SE5-A from a length of it. It originally had a alum.U channel for the boom but what i did is cut the tube the full length of the fuse I wanted and did an angle cut a 1/2" down from the top and 1/2" from the bottom. I then cut about 3" off the length of the piece I removed and I then screwed it to the fuse in 6 spots to give it torsional strength.I cut a tail and stab out of balsa.The rudder fin i put 2 pieces of balsa on either side and a thin piece of ply on the top of those for blind nuts to bite into. I then bolted the stab on the bottom with the screws going up through into the blind nuts in the fin in the channel at the rear of the pvc tube that was left open. I cut an opening for servos and made a ply motor mount that was screwed to the inside of the tube. The wing was a flat bottom wing so it just sat on the tube covering the servo opening. It was alot stiffer then the alum. u channel that the original Duraplane was. It loved to flat spin like a boss. May try a twin tube EDF or a rear motor F22 out of the tubing also. Lots of possibilities.
How about a prop and edf? Have a front mounted prop, assign a separate channel and a flick of a switch and the edf kicks in. You could have the motor seating into the pipe, but the pipe a larger diameter than the motor, allowing air intake as well as perhaps forced air intake from the prop.
No tube but about 1959 I rigged a baby bottle with a Cox .049 mounted on the cap. Big wing and tail feathers, flew it ukie full of fuel. We actually switched pilots several times but the sun was setting and all of us were staggering dizzy when the flight ended. Still had plenty of fuel left . . .
A few years ago,my late flying buddy and me built a couple of shoulder wingers using 50mm square downpipe.Iirc,the wing was flat bottom,about 4ft. span.
My mate got carried away,and stuck a .40 on the nose.I had a .32,cause thats what i had to hand.
They flew ok,but fairly fast,because they were quite heavy.Landing needed plenty of speed,or it would drop like a brick.The servo's for rud/elev/thr were in the fuse,the aileron ones in the wing.
If you wanted to build an electric version,better stick a BIG motor on the front,using lots of battery power.
It still wouldn't be a very nice flier,cause that damn pipe is too heavy.
Lets progress ... pipes ... and ducts ... and lightweight ?
Old cardboard tubes such as kitchen rolls ... toilet rolls .... etc. have long been used as formers to create tube ducts round. Whether it was balsa strips in old days or foam strips .. or even rolled foam sheet ... the cardboard tube provided the round item to form on.
So why not develop on from this ? How about using the cardboard tube ... light coat of resin to harden it up ?
OK .. let us take a block of foam that you intend to create a fuselage from ... maybe it needs a clean duct ? How about a tube cutter ? That plastic pipe can be sharpened up to provide a clean duct cutter through the block ... without having to plank or form 1/4 diameter blocks ...
That's exactly what I had in mind! I flew my duraplane into the ground (literally and figuratively) I tried everything to kill it. The wing was indestructible as it had a aluminum spar and epp foam with a soft plasticoat skin. I replaced everything on it 4-5 times but couldn't kill the wing. Had a 25sf OS so it had plenty of power. It was a flat spin king. Would do it better the almost any aerobatic plane. Go 28 revs once till it belly flopped. Only flattened the alum. gear. Straightened it out and went again. It was like a Toyota, you couldn't destroy it.
PVC wall thickness means WEIGHT. Even thin wall standard pvc pipesf will be heavy especially aiming for a 50mm fan.
You can reduce weight by not going full circumference tube the full length of the model. I'd consider cutting the pipe sort of tapered leaving just the top appx 1/6 by the time you get to the tail-planes. Or go to a flying wing and just having pipe length slightly more than the wing chord. Or use something other than the pipe as the main fuselage an just use the pipe for the fan duct.
Any of these are still going to be heavy compared to more traditional ducting.
EDF tend to be overweight without the "help" of the PVC full length fuselage to compound the issue.
THe "SPAD" planes using the square downspout material tend to be quite heavy compared to other construction methods.
For the eflux cone I'd look for a plastic cup. Save weight vs tapering the PVC.