SpudFiles

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i was wondering if anybody has any experience with square aluminum tubing. in asking because for a summer project i want to build a large scale RC aircraft. i want a wing span of about 10 to 12 feet. i wanted to use the aluminum tubing as the fuselage. i had a small plane that had tubing as the fuselage, but it was only about 2 1/2 feet long. the advantage of aluminum over wood is it can be lighter.

i just want to know how flexable it will be. i want it to be rather stiff.

if anyone can think of a better fuselage let me know, wood is not an option because it has to be strong and very light. please dont suggest balsa wood, i know its light, but it is fairly weak.

mcmaser part number 6546K13

edit- the fuselage will be about 6 feet long.

also, about how much will this weigh? its 6 feet long, 2'' on each side, and .125'' thick?

I personally think that if you want a light, yet strong metal titanium is the way to go. however that can get very expensive very fast. So I think that your choice of aluminum would be the most cost effective way to go.

yes, i doubt i will go with titanium. this is the plane i had that was made with an alluminum fuselage:

http://www2.towerhobbies.com/cgi-bin/wt ... XHCJ1&P=ML

The Red Barron!! I like it. Like I said before I think aluminum will be your best bet if your not going with titanium.

i reccomend finding EVERY formula for aircraft possible and applying it to your plane. dont wanna see you dump tons of money into a home-built plane that doesnt fly (trust me, ive done it, exept it was an RC hovercraft).

all i know is that real airplanes are made of aluminum. i reccomend an aluminum frame and then covering the entire thing in the pop can sheet............. hehe. that would be like the outer covering. i think 1 plus side for having 100% aluminum wings and fuselage is that if you crash.......... bah. your plane just bounces back, and if it breaks, just weld a new chunk on. wood its not so easy.......................

i fly planes as hobby.

its planes first and cannons second for me. although i do love me cannons.

i was going to make the wings out of wood and cover it with monokote, its a type of plastic covering thats is fairly durable and can be fixed im about two minutes if it tears. the entire wing will weigh about 7 to 10 pounds. aluminum wings would weigh way too much. i am going to use a weed eater engine and a 2 foot prop. the whole plane by AMA law can not weigh more than about 60 pounds.

i think i will make the wing ribs out of ply wood and balsa wood. one rib balso, one rib ply wood, one rib balsa..... it will make i strong and light.

the key to making airplane ive learned is making them light.

make the main support for the wing, (you know, the big long stick that extends the entire length of both wings) out of aluminum tubing. the rest could be wood i guess............ dang. i wanted to see a soda pop plane..........


EDIT: WOWW im dumb. you wanted to make the fuselage out of aluminum...................

i dont see how that WOULDNT work. if youre using a weedwhacker engine youre gonna need that kinda strengh............

im going with the weed eater engine because its is about $50, where as a airplane engine of equivilant power is over $350.

do the math. weed eater engines are also a little more rugged than airplane engines. it may vibrate a little more, and may be slightly heavyer but it should be ok as long as i do a good job building the plane. i am designing it to fly slow. around 30 mhp that way i dont need flaps, kinda like a crop duster airplane.

Merged:

anyway, i still need to know if this is ridgid enough or not. does anyone have any clue as to how much this will bend?

i know stop signs are supported but square tubing, but its thicker than what im goingto buy.

It depends on the lenth of any build sticks/tubing to how much give it will have. The longer the tubing the more bounce, the longer the stick the better the chance of cracking. If your trying to keep cost down don't use Monocoat to cover with, you should know thats out of price range for that amount of it. Use old bed sheets for wing covering. Strong, light, easy to work with, and probly allready have them. You could also use roof flasking sheet metal for the fuselage. You will pay way more then $300.00 for a airplane spacific engine to power a plane this size, even off Ebay. O.S./Magnum/Enya ect....would be way more relieable then any weed eater engine, all weed eater engines spit pop crack once they are 300 feet up, no matter how rich you run the mixture. US Genral makes the only relieable weed eater size 2 stroke, but very costly, starting at about $900.00 and up. But sounds like you allready have one or got your eye on one. What kind/brand is it? You can some times find prop hubs on Ebay for around $25.00 or so. Better have strong servos to move a rutter and flap those sizes, and plenty of battery to power them. Where are your wings going to mount, low? middle? high? Any polyhydrol joints/angles in the wing design? It's a shame SkyHighRockets was taken down, there was a great discussion on wing design there, one of the members built a rocket plane, turned out nice. Get some diagrams up.

the wing will be designed for great lift, so its will be fairly large. its will have about 6 or 7 degrees dehidral and will be mounted on top of the aluminum tubing.

4 channel, aerolons, rudder, elevator and throttle. the tail will be very basic.

this thing is litterally going to be a square tube with wings and an engine.

as for servos- standard sevos put out more than plenty for this plane. it will just be a big slow plane.

look at my second post in this topic and follow the link, that is litterally the design i want to follow. i had that plane for a few years and just want to make it much bigger.

to power sevos i will just have a single cell li-poly battery about 800 mAh or so, that will give the servos power for several hours.

i wish i could draw my planes and post them, but i only have paint and that wont work for an airplane.

the wing will be a "modified flat bottom", as that is what will give me the most lift.

lately ive spent alot of my time here

http://www.airfieldmodels.com/informati ... /index.htm

wow. ive decided you are my hero now. ive always wanted to make an RC airplane. did LOTS of reasearch, then realized i didnt have enough money............

sighhh. just post it when its finished.

and a peice of square tubing as the fuselage should work completely fine. as long as its thicker than a soda can.............. a good deal thicker.

gaa why did i never think of that................ (save money.... sighhh)

ooo and i have another question unrealted to aircraft. has anyone ever made a spudgun barrel out of square tubing? you could heat it up and twist it and have rifling.............

lol, the rifling made me laugh. i wonder how you would screw in a square plug.


planes are cheap if you know where to get them.

go to your hobby shop and get a kit, they are like $30 and fly just as well as the already built ones.

i will post it when its finished, but dont expect anything for about 2 or 3 months, as i too need money,

OK, the park flyer. Yea they are simple, and top mount wings are easier to fly as well. Build wide control surfaces, quicker to turn. Are you going to cut your own prop, or find a used one? APC makes fiberglass props that are bad to the bone preformance wise. Uglyer then death warmed over! I was running a 9X7 on a OS .40 with a modified exhaust, turned 10,000 RPM'S according to my Dura-tach, i thought it was going to leave the test stand.

top wings are no easyer to fly than low wings, there is no aerodynamic over the two, but top wings are better to learn with because the are more forgiving during landing.

anyway, i am starting to cut ribs for it, they are about a foot long. i am aiming for a 10 foot wing span and i think i am going to use a proper engine. i also think i will use a smaller prop than i originally wanted. i think about a 14-16'' will do.

@jrrdw- what kind of plane is the OS .40 for? trainer, sport?

edit- i have nearly finished the right wing's frame, i just need to get some wood glue to glue it all together. it messures about 55'' wide. add that to the left wing and it will be 110'' wide plus the center peice and the plane will have a wing span of about 115''. i just realized that this thing is a monster!

The .40 was for testing a exhaust mod i wanted to try for the airplane engines. Worked great! Went from a smooth running 7,000 rpm to a smooth running 10,000 rpm. After i knew it worked, i resold it for a nice profit! The Ebayer that bought it sent me a email praising my work and tech tips, he put it on a areobatic moddified Hornet. It's got more then enough power on demand now he said, he also said everyone at the fly field wants to buy it from him, he said no way! Not for sale! If i had the/a clean enough place to do these on a regular basis i would start taking customer orders for build up's. I would also need to upgrade my tools to do this regularly.