creative minds needed.....2m project

[kc2iso]

Hey guys....
I have some idea's that I've been kickin around for the past 2 weeks. I was trying to research the web here for some info during this time. I've come to the conclusion that this is possible.
ok...
I have a left over un-used 2m wing. Still needs to be coverd, but other then that it is built. It's from the Daydream glider kit. I think it was a Dynaflight kit to be exact?!?!
Anyway...The wing is just going to sit and collect dust as it has been. So in my little pea brian mind here, I've been thinking of using it to build a complete glider.
I have a LOAD of used..(but not beat-up) carbon arrow shafts that I no longer use. Daddys got a new set ;)
My shafts are pretty long as I have a very long draw on the bow. In fact I measured the shaft along side my other 2m plane, and I do belive thy are plenty long enough.
Now as for a pod/fuse, I have some plastic tubes that had some kinda protien(sp?) shake in them..(powder form). have about 12 of these laying around. When I can, later on tonight I take a pic of this stuff....shaft, wing, pod, ect.
But for the moment the pod looks like a glass science tube that you would see in class, tv shows...get the idea. Only diffrence is mine are plastic and abit larger. I'm sure I could fit a batt. in their along with servo's, rx, ect.
Before I forget to mention....I even have the tail feathers from the Daydream.
So all in all whatcha tink?
As long as I/we can come up with securing wing to pod, and gettng cg, and incedence(sp?) correct this should fly like a bird no?
Jeff

[Mtntop]

It'll work but I would suggest using 2 arrow shafts stacked on top of each other with maybe 1/32 ply epoxied to their sides to make it stiffer. Leave a gap between the shafts and you have room for linkage. This is what i did to my Sundancer boom. Then getting the decalage between the stab and wing and then playing with cg and away you go!

If you can use a full flying stab, that will help out in adjusting the decalage.

[ozmo01]

Hi
Some plastics are rather easy to mold or reshape. Gutter pipe for spads can be molded with heat from your covering gun. I have also molded plastic bats for SSC combat fuses in the oven. Lots of plastic containers have been recycled for vacuum molding.

[scaflock]

It should work as long as the carbon arrows are large enough to let you run control push rods through. I've got a ton of carbon shafts as well but they're only 26 inches long as I shoot with an overdraw. Hummm Maybe a small DLG could be made with them.

Jeff

[lincoln]

Suggest a bundle of three shafts. That way the boom will be stiff in all directions. One arrowshaft, or at least one like the ones I've seen, isn't even stiff enough for a 60 inch hand launch. (And I do mean hand launch. On a DLG it would probably fall apart instantly or pitch down into the ground and smash.) I think, actually, that the easy way to make the fuselage is probably just a balsa box with some doublers or something. Check out the building instructions for the Chrysalis at DJ Aerotech and you will see that a fuselage can be quite simple. Second easiest way probably to use a bundle of the shafts for the boom. If you want to make it more difficult, I think it would be cool to take a PET soda bottle or similar, heat it up to stretch and form it into a nice smooth pod, then cut in middle so you can construct a sort of plank in the middle that it slides over with the servos mounted on/in the plank.

I think it's a great idea to use your existing wing and tail.

[kc2iso]

Please keep it coming. This is all very helpful.
My arrow shafts are roughly 3/16". I don't have my calipers handy at the moment but I will try to get the thickness later on today.
Last night I was toying around with one. Just grabbing both ends and seeing just how far I can twist. And to be honest I can't get them to twist at all.
I have yet to launch from a high-start but tat is the plan. I didn't think this syle of launch had much force acting upon the plane. Not unlike the DLG. With that I know there is a tremdous amount of force. I thought one shaft would be fine.
What is PET? And is there anything on the net that could help me in the way of shaping it into a fuse or whatever?

[DKChris]

kc2iso wrote:
What is PET?

Here is a thread with some video examples of what can be done with it; PET/PETG description link in post #6

I'd recon you could use the terminator hlg build pages for a usable reference for sizes and stuff - just scaled up:
http://www.charlesriverrc.org/articles/terminatorhlg/terminatorhlg.htm
It's a 1,5m javelin style handlaunch plane with an arrow shaft for a tailboom - maybe you can reference the spline of your arrows to that of the recommended types in that plan to get some idea of just how strong/stiff a tailboom is neccesary. Handlaunch IS harder on the boom than histart! Especially dlg. But there's still quite a bit of force applied to the boom in histart, especially just after release.

Or maybe u can use the allegro / allegro lite plans same place:
http://www.charlesriverrc.org/articles/allegro2m/markdrela_allegro2m.htm and http://www.charlesriverrc.org/articles/allegrolite2m/markdrela_allegrolite2m.htm
These are some top of the line histart 2M RE/RES planes, thought up and constructed by HLG aerofoil guru Mark drela.
There are some references on how to evaluate boom stiffness on the lite page : http://www.charlesriverrc.org/articles/allegrolite2m/boomstiffness.txt

Stay close to the original length between TE and tail section of the daydream if you want to reuse the old tailfeathers though. Otherwise the balance between boom length and tail size will be altered.
If you dont have that number, it ought to be possible to refind it by referencing it to other similar gliders (including the allegro's) by comparing the number equivalent to : (approx. distance from wing main spar to middle of stab+elevator area) times (stab+elevator area). Basic idea is large tail area = short boom and vice versa.

[Skycruiser]

Here's a link (http://www.randallfroude.co.nz/pod%20and%20boom.html) to how I did it. That was using a 3/8 fibreglass tube, I had originally thought it was carbon but it just had a black coating on the outside to make it look like it.

Worked very well, except pulling out of a very fast dive was difficult, I think up elevator just made the boom bend down. Otherwise, flight performance was way better than the original with the lighter weight and less parasitic drag.

Nick

[Skycruiser]

Please keep it coming. This is all very helpful.
My arrow shafts are roughly 3/16". I don't have my calipers handy at the moment but I will try to get the thickness later on today.
Last night I was toying around with one. Just grabbing both ends and seeing just how far I can twist. And to be honest I can't get them to twist at all.
I have yet to launch from a high-start but tat is the plan. I didn't think this syle of launch had much force acting upon the plane. Not unlike the DLG. With that I know there is a tremdous amount of force. I thought one shaft would be fine.
What is PET? And is there anything on the net that could help me in the way of shaping it into a fuse or whatever?

From memory PET is polyethylene tetraphthalate, although it's been over a couple of decades since I looked in a chem textbook! As such it's the same as plastic soda bottles. Make a plug out of pine or mdf, slip it inside, then shrink the PET over it with a hot air gun. There must be heaps of sites on the web showing how to make canopies the same way.

Niock

Nick

[lincoln]

Unless they've changed the plans, the Terminator tailboom is too flexible. I've seen it, and I've even flown it myself, if memory serves. (A long time ago.) I don't have a good arm, but I could see the effect. You could easily get the same speed pinging off a high start in a moderate breeze.

As far as twisting the boom, I'm not sure about that one but I suspect the torsional stiffness isn't that great. Try gluing a tail sized piece of wood on each end and then try twisting. My Mantis tailboom doesn't feel flexible when you try to twist it in your hands, but it sure does twist in the air.

Boom torsion isn't just a function of diameter, though that's important. Fiber orientation matters a lot too.
Here is a thread with some video examples of what can be done with it; PET/PETG description link in post #6

I'd recon you could use the terminator hlg build pages for a usable reference for sizes and stuff - just scaled up:
http://www.charlesriverrc.org/articles/terminatorhlg/terminatorhlg.htm
It's a 1,5m javelin style handlaunch plane with an arrow shaft for a tailboom - maybe you can reference the spline of your arrows to that of the recommended types in that plan to get some idea of just how strong/stiff a tailboom is neccesary. Handlaunch IS harder on the boom than histart! Especially dlg. But there's still quite a bit of force applied to the boom in histart, especially just after release.

[DKChris]

I must have somehow F'ed up on the link to the pet description in my first post. Here it is :
http://www.rcgroups.com/forums/showthread.php?t=823242

[atjurhs]

Just go buy a 2M fuse from ArtHobby, they're cheap, and ther's plenty of selection.

You know you'll get something that works and can easily mount a tail onto. Get it in the air and go fly rather than tinkering around with stuff you're not sure of. Unless that is the goal, to tinker with stuff you're not sure of..

[Gavin Trussell]

I have made dozens of small gliders using arrowshafts ,dlg's mostly, the arrowshafts seem strong until you see the tail wag on launch and i cant even imagine a two meter on a winch with a arrow boom . The 2 or 3 arrows together would work but a carbon golf shaft that any golf proshop has used for about five bucks is a much better idea. You can hotglue foam on the end of it and sand a sweet pod out in the shape you need.then stretch a baloon over it and some hobby poxy and some fiberglass cloth and stretch another baloon over the whole mess and wamo two meter pod and boom. Cut the cannopy out after it's set up and pour acetone into the pod and it will desolve the foam. A small bulkhead to suport the shaft and your good to go.
Just an idea for you on a one off . It worked for me back in the day
Gavin