HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 21, 2013, 12:26 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
Quote:
Originally Posted by jimmy boo View Post
^by spars do you mean support bars?

anyways, I don't plan on using support bars, the trick will be having one 30 inch by 4 wing, then having the same cutout with a inch by 30 cutout. placing it at the front and covering with packing tape, thus producing a basic airfoil. the 30 by 1 inch piece will act as a support.

I am not sure about the who dihedral thing, Ill look into it.
When you say support bars are you thinking "struts"? Hooked to the bottom of the wing say about half way out and then on an angle hooked to the bottom corner of the fuselage and support the wing?

A spar is something imbedded into or fastened to the top or bottom that runs the length of the wing and gives it some stiffness.

http://www.homebuiltairplanes.com/fo...apersketch.jpg

If you are thinking what I think you are with the piece of 1 by 30 on the leading edge of the wing to make a stepped airfoil, that piece will act as a type of spar.
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 21, 2013, 12:46 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
Hmm, I have an idea, check out my plans. MY wings won't exactly be bent, but they will be bent while leaving the fuse lodge, i.e. i would put some sort weight under them, and they would now be angled further up.

sorta like this,

http://images3.jetphotos.net/img/1/0...1281458350.jpg

the wings are straight, but facing up, a bit.


now, heres my plan. I still have a few unknowns, like how long to make the fuse lodge, also if my elevator and rudder are ok.

crude model:

http://www.flickr.com/photos/3564195...in/photostream


plus, I need help choosing servos, motors, battery, ETC....


need a lot of help with that. I am terrible at electronics.
jimmy boo is offline Find More Posts by jimmy boo
Reply With Quote
Old Jan 21, 2013, 12:54 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
great, not sure if my message went through so ill just post it again,

my idea is to make my wings still straight but angle them up a bit. Like this,

http://www.flywestwind.com/Hangar/Ai.../B741front.jpg

Here are my curve plans.

I still have some question, like how long should i make the fusleodge, are my elevator and rudder ok?

My last question is what do I need, what is recommended, i.e. servos, motors, controller ETC. I don't have too much $$ so I am not going all out here.

thank you all so much!!!!

heres the pic of my CRUDE plans:

http://www.flickr.com/photos/35641952@N08/8401856867/
jimmy boo is offline Find More Posts by jimmy boo
Reply With Quote
Old Jan 21, 2013, 01:13 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
That's the right idea, the wings can be straight in all other dimensions, just angled up.

This could be a good resource for some ideas:

http://spadtothebone.net/index.html

I think your dimensions in the picture are looking like a good starting point. Whatever you do it will fly as long as the center of gravity is in the right place with respect to the center of lift. Different fuselage lengths and tail feather sizes will just change the flight/stability/turning characteristics. Try it out. If you don't like it, change it.

A quote:

The next design parameter is the fuselage, or aircraft's body length. A fuselage length of 75 percent of the wingspan is a good starting point. For an airplane with a 20 inch wingspan this will result in a fuselage that is 15 inches long.

From here:

http://articles.submityourarticle.co...ameters-269031

Good starting point for inexpensive engine etc.:

http://www.hobbyking.com/hobbyking/s...er_1100kv.html

http://www.hobbyking.com/hobbyking/s..._BEC_BESC.html

http://www.hobbyking.com/hobbyking/s...cro_Servo.html
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Old Jan 21, 2013, 01:17 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
^sweet glad to get some input.

that all looks good, what about receiver controller?

also with the motors combining for about 75grams how heavy can the battery be?

also, are the motors strong enough?

sorry for all the questions.
jimmy boo is offline Find More Posts by jimmy boo
Last edited by jimmy boo; Jan 21, 2013 at 01:34 PM.
Reply With Quote
Old Jan 21, 2013, 01:35 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
How cheap do you need to go with radio?

Really cheap:

http://www.hobbyking.com/hobbyking/s...2_Mode_2_.html

Some of the reviews talked about DOA units with shorted out blobs of solder and broken wires. Poor quality control but you might luck out. Or you might have to take it apart to check for problems.

A bit more but probably a bit better:

http://www.hobbyking.com/hobbyking/s...y_Mode_2_.html

I think you can do a lot with prop choices and make those motors fly that type of airplane pretty good.

You're probably rockin' with a battery like this:

http://www.hobbyking.com/hobbyking/s...Lipo_Pack.html

Thinking of your wing I might be tempted to go more like 5 inches wide. Would make it so it would fly slow easier. Would reduce your wing loading and allow slower flight.
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Old Jan 21, 2013, 01:48 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
transmitter wise, I guess the $24 one sounds kinda garbagy,

64 is a bit too much,

Idk, maybe something in the middle.

I still want a full range transmitter though.


what do you mean go "5 inches wide."
jimmy boo is offline Find More Posts by jimmy boo
Reply With Quote
Old Jan 21, 2013, 02:14 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
Quote:
Originally Posted by jimmy boo View Post

what do you mean go "5 inches wide."
Instead of 30 by 4; 30 by 5.

5 inches from leading edge to trailing edge of the wing.
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Old Jan 21, 2013, 02:19 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
ok, so now I would have 150inches2 of wing area, excluding the amount spent in the fuse lodge. In theory since I am making the wing bent backward and in height, the wingspan will probably be closer to 31ish inches.

Those engines still powerful enough?
jimmy boo is offline Find More Posts by jimmy boo
Reply With Quote
Old Jan 21, 2013, 02:19 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
Quote:
Originally Posted by jimmy boo View Post
transmitter wise, I guess the $24 one sounds kinda garbagy,

64 is a bit too much,

Idk, maybe something in the middle.

I still want a full range transmitter though.
I got one of the 24 dollar blisters for a goof around project and it works fine. Not a problem with the range and that, just sometimes people found QC problems. That comes with a receiver also. The Orange one does not.

If you hunt around for FrSky they have economical units too.
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Old Jan 21, 2013, 02:26 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
ok, and you think thats all i need?

what about a recover on the plane?
jimmy boo is offline Find More Posts by jimmy boo
Reply With Quote
Old Jan 21, 2013, 02:29 PM
Damn this gets addictive.
Thechittyfather's Avatar
United Kingdom
Joined Oct 2011
530 Posts
I found this a useful read when I started putting my own designs together. Might help get your first build in the air without too much hassle.
http://adamone.rchomepage.com/design.htm#calculate
tCF
Thechittyfather is offline Find More Posts by Thechittyfather
Reply With Quote
Old Jan 21, 2013, 02:31 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
Quote:
Originally Posted by jimmy boo View Post
ok, so now I would have 150inches2 of wing area, excluding the amount spent in the fuse lodge. In theory since I am making the wing bent backward and in height, the wingspan will probably be closer to 31ish inches.

Those engines still powerful enough?
Generally speaking more wing area would allow you to fly with even less power. You don't need to get it going as fast to produce enough lift to fly. Of course with larger wing there is a bit more drag but that should be more than offset by the increase in lift and it will be a net gain. It all does depend on the shape of your airfoil but if you make it like your picture with a flat bottom it should be a decent high-lift wing.

Either way I think you have tons of power in those motors to fly an airplane of the weight you will end up with.

I fly a 50 inch flying boat that weighs a bit over 3 pounds with a Park 480 only pulling less than 200 watts and depending on the prop I can have it zooming around with incredible speed or floating around practically like a glider. It has a very simple flat bottomed airfoil with lots of dihedral and will fly rudder only just fine.
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Old Jan 21, 2013, 02:33 PM
No bounce, No play.
davidmc36's Avatar
Canada, ON, Ottawa
Joined Oct 2010
3,690 Posts
Quote:
Originally Posted by jimmy boo View Post
ok, and you think thats all i need?

what about a recover on the plane?
recover??

Oh wait, did you mean to say reciever? Many of the low budget radios come with recievers. That Turnigy one I linked does. The Orange does not, but HK has them for only 6 or eight bucks.
davidmc36 is online now Find More Posts by davidmc36
Reply With Quote
Old Jan 21, 2013, 02:34 PM
Registered User
jimmy boo's Avatar
United States, MA, Boston
Joined Dec 2012
638 Posts
^meant to say receiver

thanks, I like the power thoughts.
jimmy boo is offline Find More Posts by jimmy boo
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Best method to make self contained pan and tilt? Deadstick 8409 FPV Talk 5 Jan 16, 2013 10:01 PM
Sold FY30A new Aircraft stabilizer & cam stabilizer Tom.in.Maryland Aircraft - General - Radio Equipment (FS/W) 5 Jan 11, 2013 07:03 PM
Discussion Self stabilizing through vertical fins? KillerCut Flying Wings 12 Sep 10, 2012 08:16 PM
Build Log Quadro from Finland (self made stabilizations) tzouni Multirotor Talk 4 Jan 08, 2012 06:32 AM