RC India

Hi friends I was searching a trainer for teaching me balsa building but now going for a coro plane.Started building my first coro trainer from plans.Besides my work n exam preparation I'm hardly getting time for building,so I don't know when I'll finish this one.uploading build pics.
Specs:
Material: 3mm coro for everything
Wing span: 1250mm
Fuse length: 895mm

some more pics..

Where did u get the plans? Is this the SPADET trainer.

No,this is the AVISPAD trainer..

more..

Final fuse..

Are u putting an electric setup or do u plan a glow engine on this plane. If u are planning a glow engine then I feel a 3 mm coro fuse would be too light and would have a lot of torsion.
Waiting to see the rest of the build.
Best wishes for the build.
Doc

Thanks Doc..I'm planning to put electric set up..

krish,

which build plan you are following? please do share it

Regards
Dileep

Will post the plans..I'm still confused about the wing spar..Don't have 4mm coro to use a coro spar..I found some 2.5mm light weight wooden material used in plywood door installation..Planning to use tat..Any suggestions?

try to find beech wood,used as beeding for door,window etc,available in different sizes in any wooden shop & ask for plain one!

Thanks praveen..I'll try tat..

Quote
krish,

which build plan you are following? please do share it

Regards
Dileep

The original Avispad Link => http://www.rcgroups.com/forums/showthread.php?t=893170 (http://www.rcgroups.com/forums/showthread.php?t=893170)
Guess this is the one Krish is following too. Its a very cool trainer if done light.
Hope this helps.
Edwin

Quote from: xxkrishxx on September 12, 2010, 07:49:06 PM
Will post the plans..I'm still confused about the wing spar..Don't have 4mm coro to use a coro spar..I found some 2.5mm light weight wooden material used in plywood door installation..Planning to use tat..Any suggestions?

You can make a spar by folding a strip of 3mm coro like a triangular tube. I have used this design in a SPAD and it works well.

Hi sunlikestar this is entirely a new spar method,guess it'll be cool one..Can u tell me the flute direction in tat spar?

Quote from: xxkrishxx on September 14, 2010, 01:09:04 PM
Hi sunlikestar this is entirely a new spar method,guess it'll be cool one..Can u tell me the flute direction in tat spar?

flutes run along the tubes length. I discovered this when i was fixing my SPAD, the complete plane was unharmed but the spar was broken in places. I just drew it out and inserted a triangular tube like this, however atleast 40% of the center portion was reinforced with plywood sitting vertically in the tube. but this was for a .40 size glow plane. for a light electric, it should work without the plywood.

Hello Sun,

The design you suggested may be fine for small electrics but do not attempt it for larger electric / glow models. I am sure the spar would not be sufficient on these larger models. You would be surprised at the forces acting on the wing during flight.

-Ismail

Hi Ismail,

So good to see you again. I hope you remember the SPAD you helped me build. That plane is still holding up and it now has a similar spar but as i said before, its reinforced by plywood sitting at the center. i have attached a picture.
Also it should be noted that forces acting on the wings of my plane is much lower than force acting on yours  :)

Aaah.. I remember you!... Hope you are doing well.

Coming back to the spar thing. As long as you have a rigid spar at the center you should be fine. You have shown a plywood at the center and that would take all the crushing forces.

I guess the triangular tube extend cannot more than 5 inches without the spar (using 3mm coro). More than that, it may hold up but its clearly asking for trouble. You don't want to have the wing fold up on a windy day.

-Ismail

Ismail will it be suitable for my wing span?

Sun how can we calculate the base n height dimensions of the spar to out wing span? Which thick plywood u used inside?

Your model has about 4 feet wing span. It is fine to follow the method suggested by Sun but I do not see a reason if you use the plywood spar already.

If I were you, I would use a light plywood spar for the entire length of the wing span.

-Ismail

The Plan..

How can i make the triangular spar like in tat wing assembled pic? One half of the spar is horizontal n another half is 100mm up from the horizontal line..

Quote from: xxkrishxx on September 15, 2010, 01:06:41 PM
How can i make the triangular spar like in tat wing assembled pic? One half of the spar is horizontal n another half is 100mm up from the horizontal line..

I double what Ismail said, also it doesn't look like the triangle tube will hold a dihedral. Better go for plywood.

Wat should be the thickness of the plywood tat can be used for spar?

2.5 to 3mm should be fine. but make sure you select light plywood, because some are really heavy.

Now I got what you are looking for. You could use a wood called 'Reeper' by the local carpenters. It is a white coloured wood with grains running nearly straight along the lenth of the wood. It looks some what like pine. A second option is as once Ismail had told me, is to use the wood that is used by frame makers (Photo frames). This is the same wood. You will have to reenforce the center with pieces of the same wood lengh about 6 -7 inches. Place one piece of wood flat on the floor and place the second length of wood at the height that is in the plan. Again the 2nd piece is flat on the floor. mark the angle the 2nd piece is making with the 1st and then cut/ sand the first piece at the correct place. Keep the length of the pieces slightly longer than that is in the plan. U can cut the extra later.
Another option is to use 'Multiwall Polycarbonate sheet' for the spar. You can find it any place that stocks Coro. This sheet comes in a size of 4.6 and 6 mm. It is lighter than coro and when 2 pieces with flutes running perpendicular to each other are stuck together, are as strong as light wood.
A photograph of the material that I am talking about. (And the SPAD Extra I'm working on)

Thanks doc..I'll check all the three options soon..

Back to build after a gap..I've cut the elevator n rudder..When i inserted the ele for checking in it's slot as per the plan,one half of the ele is going down n not balanced one..Will it be ok after gluing correctly? Uploading the pics

Just glue it, we will find a way if it droops at one side. Have you finished the wing?

U can see the ele position in the following pic

Hi sun,i'Ve just cut down the wing pieces n spar pieces from coro..Gonna glue the spar first..

Hello frnds,finished the wing last week..uploading pics:

This is a 2piece wing..The spar is made from 3mm coro,idea given by mr.Edwin(martian2121)..Spar is built by sticking a layer of coro flutes running cord-wise between 2layers of coro flutes running span-wise..I've to glue the center wing wrap n ailerons..Glues used:Fevibond,Feviquick..

beautiful wing, by 2 piece do you mean detachable 2 piece?

pretty nice built all the best for maiden!!

Thanks sun&ash..No it's not detachable..I mean it made from 2 separate pieces of 625length coro,as per plan it should be built from a single piece of length 1250 mm..is it possible to build a detachable wing with dihedral?

i was just asking because i am planning to build one with 2M detachable wings, but right now i am out of coro :(

is it with dihedral?

right now its hypothetical, but want it to be polyhedral. 

Built another set of wing..

is this air-foil ok??

I'm confused abt the aileron dimensions..can any one help me regarding this?? I also want to know abt placing the aileron servos..planning to use Turnigy eco micro servo..is it suitable for this?

how did you stick the body?
i mean the sides of the 90deg?
please explain in detail! (:|~

@prateek:u mean the sides of the fuse?

yeah

Why did u build another wing? I mean was there a problem with the first wing?

Actually i'm buildin one plane at my home town n another one at Hubli..

@prateek: I just scored the flutes to be fold n applied feviquick,then kept between bricks..U can see tat pic in my earlier post..

nice build log krish. Best of luck with your trainer :) Which radio will you be using? Is this your "first build" or just "first coro build"?

Thanks Raj..This is my first build,I have a Spektrum Dx6i..

Can any spader help me regarding the ailerons?

What help do u need regarding ailerons...?

ailerons dimensions are not available in the plan,u can refer the plan pics,,

For trainer you could use 10% to 12% of the wing chord.

You can use 12-15% of chord length.
I have used 15% of chord length on my glider and works really good.

@Ismail:the wing chord is 200mm,so 11%of 200 mm is 22mm..so the breadth of the aileron is 22mm??

a/c to the following plan pic 20mm is extra thr from the trailing edge..

are the percentages for the breadth or aileron area?

percentages are for breadth

@Spitfire:15% means 30mm.so I've to glue it over the 20 mm portion n mane the hinge at the 20mm's meeting point?

aer you going to cut the ailerons from wing you have made or attaching them externally to wing you have made...?

I can't understand ur question spitfire.

I want to glue it over the 20mm portion

I mean to say if you are going to cut some portion from wing you have made and then glue it again as aileron or you are making new piece for aileron and then attaching it to your wing...?

new piece for aileron over the 20mm portion

Reply #22 has been updated with the right attachments :

http://www.rcindia.org/electric-planes/my-first-coro-trainer-build/msg31091/#msg31091

What i can understand from pic is that u should cut that extra 20mm portion from wing and then attach it as aileron.
Anwar am I correct...?

thank u anwar..

one guy told me in spadworld forum same as like u spitfire..he told me to cut the remaining extended portion n attach it using fiber tape..is it good way?

I think this pic from RCG also explain the same thing.
http://www.rcgroups.com/forums/attachment.php?attachmentid=1961165 (http://www.rcgroups.com/forums/attachment.php?attachmentid=1961165)

If you look at pic...there is no flat portion in wing other than ailerons.

which is the good way,cut the portion from wing  and then glue it again as aileron or making new piece for aileron and then attaching it?

I think it will not make any difference as long as you cut it properly

this is my first build so don't know which one to choose

Anyway you are going to cut the extra 20mm part so just cut it carefully and use it as aileron.
This will save some piece of coro  :)

even if i cut that extra portion,I have to make the aileron from separate piece of coro only because tat 20mm portion's flutes are running chord-wise n for ailerons the flutes should be on span-wise..am i correct??

Go ahead...just remember...even if you are building this for first time....it is not always necessary to follow plan exactly....you can always change some things as per your convenience

well my final doubt: if i build the aileron for 30mm n glue it over the extended 20 mm portion,is the remaining 10mm after the hinge enough for the flying characteristics?

would you please upload a quick sketch of  what exactly you want to do?

Sketch

So you want to use remaining 10 mm as aileron or whole 30mm as aileron...?

I m attaching pic of my wing which is 200mm in chord length.
I have used aileron width of 30mm and cut a piece of width 30mm from wing and attached them as aileron.

I want to use whole 30mm as aileron,so the portion after the hinge line should be 30mm rite??

yes ...portion after hinge line will be 30 mm if you want to use 30 mm aileron.

Thanks Spitfire..I'll cut 50mm pieces n glue it over the 20mm extended portion..

Best luck for your build...looking forward to maiden...!

Friends I'm not able to balance my elevator.after gluing,one side it touching the floor..I have inserted into the slots which i cut in the fuse..Wat will be solution for this? Lookin for help..

Can i remove it from the slot and glue it in the fuse bottom?

Any suggestion?

Spaders pls reply my question..Where r u Ismail,Edwin,R C,Flyingdoc and who ever built spad?

hi Krish,
  Glad to see u persevering with ur avispad build  :thumbsup:
I login almost every day but hardly find time to post (of fly or build for that matter) but addicted as I am to this forum, I manage to glance in every now and then.

As for the imbalance in ur elevator, if the measurements are equal in both the sides, check for flexing in the section of the fuse between the wing and the elevator. A little bit is ok. If the measurements is off in the elevator section, gently trim the extra. if the wings balance fine and the elevators look about right, u could go ahead with the maiden. Spads DieHard! or rather Hardly Die! So.......

Good Luck

Hi Krish,

I am also same as Martian, could not browse through every thead with my limited time.

Anyway, I see your problem. It happens during your early build stages but now that you have learnt it I am sure you would be more careful in your next builds. This is where you need to have a L angle tool and a spirit level.

The easier solution is to use sturts for the tail feathers. The side with the lower horiz stablizer shall have a shorter sturt connecting to the vertical stabilizer. This would ensure that the lower horiz stab is pulled up in place. Similarly the other side should have a longer sturt so that it pushes the horiz stab down. You can do the struts on top and bottom of the stabilizer to make it even more solid.

If you ask me this is an "easier" way to get out of it... but I would not prefer to have static load on any of the control surfaces.. if I were you, I would rebuild the horiz stab once again..

-Ismail

In my next fuse i'm thinking to stick the elevator in the bottom instead of sticking in the slot..

Well, its up to you.

Sticking the stabilizer in the slot is not a big deal.. it just a matter of extra caution/steps to be taken care of.

-Ismail

Hi Krish,
Same story as Ismail. Was reading some threads but not writing for some time now
Ok what I gather being ur problems.
Wing : What I do is first make the wing with the flutes running cord wise. Gives a perfect aerofoil with no angles. Is very tight with the spar so the spar has support. I first measure and cut the ailerons according to the dimentions in the plan, stick them to the inside of the lower portion of the wing and then score the fold line and stick it to the upper portion of the aileron. This way I get a flat wing. Now I put a 1 1/2 inch lipping patti (Any wood shop) just ahead of the spar line and twist it so that it stand on its side and there is space to slip in the actual spar. I use 30 min epoxy for the spar and then slip it in place and let it dry. The same is done for the other wing and both sides are fixed in the middle with a strip of coro.
Now for the fuse: I feel that the slot cut is not straight...  and or the horizontal stab has not been centered correctly. I use a right angle from a geometry set to get the horizontal and vertical stab at right angles to each other.
You could try putting spokes as struts to pull the lower side up but that would offset the weight and along with that add to the weight of the plane. Along with that, now that u have already stuck the horizontal, putting a strut would put tortional stress on the fuse and there would be a tortion in the fuse.
The pain of seeing a plane not flying well after a long build is too much.... so u have 2 choices. Make it and fly it as it is...Or.... Rebuild. Tough call.
Hope it comes out well.
Safe landings
doc

Even if the stablizer is at a angle you can still fly the plane. Remember, TLAR principle works well in SPAD designs.

Thanks for the replies friends..Can i get a list of tools to build the stabilizers correctly?

Hi Krish,
Here is one way of getting the stab and fin correct...

Mohan can u post the pics of ur avispad?

Here you are ;D...

nice one sir  ;D  :salute:
try to post the video also if possible

Hi Guys
I am building my new plane which is the Avispad. I wanted my plane to be like a glider.Can anyone please tell me how can I build a wing like this. :help:

Please

hey anyone plz help me out with a electric plane.....i want to make it as fast as possible
somebdy told me abt "oshkosh" named electric plane.....can anyone help me out with its plans or anything else....

Contact ritz (http://www.rcindia.org/profile/?u=2241), he is also in Jaipur and has just finished his first plane. He should be able to help you get started.

try this its also similar
http://spadworld.net/forum/viewtopic.php?t=15648&postdays=0&postorder=asc&start=0

http://www.spadtothebone.com/SPAD/buhor25/buhor25_7.htm

http://www.spadtothebone.com/SPAD/dpstwin/dpstwin4.htm

http://www.spadtothebone.com/SPAD/corocub/Corocub_15.htm

wat do u guys use/suggest for the wing dowel for the spad?

Thick kebab sticks, ballpens, steel rods.. any thing as long a its not too heavy.

i have seen guys using rule pencil also!

here are the Oshkosh Special Plans :thumbsup:
http://www.rcgroups.com/forums/showpost.php?p=12689264&postcount=43

Hey Krish, where have you reached with your avi?

I'm idle for some months because of exams n transfer..