hi friends,im trying to build a scratchbuilt plane,
im posting the pics,all your suggestions are welcome......
material used is high density thermocol

i think the model is not so good,but as a beginner im just trying to build my own model,the motor mount is sticked by using fevicol sh....

you should be proud of yourself if your a beginner.
Its good only... Nice Job

Important:
1)Use Epoxy (araldite) to fabricate the motor mount stick to the foam. Fevicol Sh wont be good at all. Trust me.
2)And what are the Dimensions and Weight of this model ?
3)What power system are you planning to use ?

thanq very much for your reply samanth

i will use araldite as you suggested for the motor mount
the weight of the model without the electronics is 280gms
the power system i have with me is 1500kv motor,tpro 9gservos,2s1p 1000mah battery,30amp esc

when i done a test on the plane using a 1047 and 8040 props it ie moving very fast and it had very good thrust with 1047 prop(as i hold the tail part with my hand),but when i used 8040 its is moving very slowly
u can check the motor properties here
Rotational Speed
2600 RPM/V
Free Load Current
2.0A
Max. Current
8A-20A
Input Voltage
6 - 22V
Max. Efficiency
98%
Weight
44.46g
Motor Dimensions (Diameter x Length)
27.8mm x 23.0mm
Shaft Diameter
3.00mm (Front and Back)
Speed contorller requiement
20A
Input Battery Types
NiCd/ Nimh/ Li-po Battery
Recommend Model
Airplane

Hmm...using a 20A ESC for a 20A motor will generate quite some heat, just make sure you dont run it at 90-100% throttle for a long time.

I am not sure if this will work for high density thermocol, but you can try this -
sand the leading edges of the wing and nose using 320grit Sandpaper or Emory sheet. It will really really help and I have had excellent gliding performance with my models after sanding.

it works with this material,and i had done sanding with Emory paper of different grade,i used kfm2 airfoil,i have to test the flight at no throttle whether it glides or not,but still have 2 doubts  ........
1.the length of the plane is 96cms and the length of the wing is 1mts without dihedral,so can this wing will be able to create a good lift?
2.how to design the rudder and elevator?

@Harsha
 I think ur total weight with electronics part will be approximately 380 gm .That's good.
 U mentioned that ur length of ur wing is 1m but not mentioned  breath of it.
 plzz give the details of ur plane including actual weight with plan, will help us to solve ur problem.

And for rudder and elevator it is not easy to make it using thermocol.Use coro sheet .Cannot found?
Ok go to nearest cellphone card recharge shop and tell him to give a small advertising sheet of any telecom company.Really they print using coro sheet.
Plz refer the images.

For more details follow this thread
http://www.rcindia.org/self-designed-diy-and-college-projects/glidiator-my-first-trainer-build-log/

@sultan:thanq bhai,i used coro material for rudder and elevator,by the way the length of the wing is 1mt and chord of the wing is 27cms,im thinking to use kfm2 airfoil

Give ur wing aerofoil shape.And also mentain ur cg correctly.I have also made like one .The design is overall complete.
In 5 or 6 days i will post the pic
Ur wing size is sufficient for lift and remember to give aerofoil shape to it.

sure,i will update the progress soon

hi everyone,
some more pics,i made the wing with kfm2 airfoil,let me know if i made any mistake in making the wing
wing profile:
kfm2 airfoil(i used one thermocol sheet,cut down into two pieces,sandwiched them one on the other and sanded the trailing and leading edges)
1mt length
27cms chord

The step should be at 50% of the cord, the top layer of thermocol should cove only half the cord. Also you will need a sharper leading edge, sand both top and bottom surface equally.

Refer:
http://www.rcgroups.com/forums/attachment.php?attachmentid=3433154

my doubt is that im using a 1500kv motor with 8040 prop and 2s 1000mah lipo
but the plane is not moving at all when it is given 50percent throtle,it hardly moves when the throttle is given full,how to solve this problem and make it fly?
and where should be the c.g of this plane?

Quote from: SunLikeStar on May 19, 2011, 07:08:35 PM
The step should be at 50% of the cord, the top layer of thermocol should cove only half the cord. Also you will need a sharper leading edge, sand both top and bottom surface equally.

Refer:
http://www.rcgroups.com/forums/attachment.php?attachmentid=3433154

thanq,i will modify the wing now

What is your planes total weight?

i didnt measure yet but it will be not more than 480gms thats for sure

Then you should have enough power with this setup. Finish your wing and then post some picture of your completed plane.

Have you put in the prop correctly? Like the "8X4" written on the prop should be facing outwards away from the plane.

C.G should be at a distance of 1/3rd the total chord length from the leading edge.

@sunlikestar:sure bro
@rohitgupta:ya the prop is facing outwards away from the plane
ya the c.g is little bit further like 1cm,i think this made it nose heavy,when i throw the plane it glides well,but when it is kept down and tested for the movement,its moving heavily...

harsha 
Try  sanding  the  front  part of  the wing  with  a  sand  paper    so that  it  gives  some  aerodynamic  shape 

may  be  like  this !!


seniors  suggest  Us.....         (I am  a Newbie too ..   ) 

i modified the wing here are the pics,let me know if there is any mistake,i will try to rebuild or change the wing

I doesn't look like KFm2 anymore but i'm sure it'll fly 

Since you have come this far, I thing you should finish it but coro would have been a much better substitute for this thermocole.

Quote from: rohitgupta322 on May 20, 2011, 09:25:44 AM
Since you have come this far, I thing you should finish it but coro would have been a much better substitute for this thermocole.

ya,but coro is comparatively heavy material so i used this material,instead od kfm2 airfoil can i take a flat wing????will it make the plane fly better???

I have a bigger concern, from the pictures it looks like your wing doesn't have a dihedral. Its an absolute necessity if you are a beginner.