RC India

Hi to all ,
               I need ur help in selecting all my electronics for my BLU BABY 24" . Its total weight without electronics is 88 gms.
               Im thinking about the following setup:

http://rchobbyaddict.com/product_info.php?cPath=53&products_id=144
http://rchobbyaddict.com/product_info.php?cPath=25&products_id=115
http://rchobbyaddict.com/product_info.php?cPath=24&products_id=161

is it good to go??

hoping for a positive replies, specially some suggesions frm seniors .

thank u ..!!

here r some pics of my model :-

here r some more pics :

hi mate.
that will be a nice looking plane...........
you say it is 88gms the motor and esc you chose gives specs and says for 500 to 800 gm plane.this would be way too big I think.
regards
don

HI Saurabh,

its nice build!!!!! packaging tape used will strengthen  wing....
good job!!!

abt power setup......no ways... this setup is not for ur plane.... it is way toooo powerful and heavy for ur plane...

u need motor with thrust of around 130-160 gms.... i think 12gm or 16 gm Brushless motor would be enough...
with at the most 10A ESC and 2s 300-400 mAh Lipo....

i hav made one small plane with wingspan of 20" and weight with all electronics and without battery is 90gms and i am using HK 1811 (11gm) motor, and i feel i it is over powered. To fly this plane i need only half throttle...if i increase, it goes up... this could be thrust angle issue...but still...

i will not suggest 1811, but try out hextronics 16 gm motor, i even think this is little overpowered... but atleast u can try it on this...
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=6311

check out my 90 gm plane: scrappy @
http://www.rcindia.org/electric-planes/small-20'-wingspan-plane-from-scrap-biofoam!!!!!!/

i have one 15 gm brand new motor with me...but only issue is it is high kV motor, can be used with 15" jet plane..
and may not suite ur application..
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5383

all the best..keep posted

Ashish

@ sunk? - thanks sir , i know that the motor is for 500-600 gms . model but is it AUW or jst weight of model without electronics? i thought its AUW that is why i selected those, bt frm ur reply i think its jst weight of body ( fuse, wings, tail etc..) so thanks again i wll think on it n wll search on some different..


@ ashJR7202 - thanks sir for ur detailed explanation ,

i jst hav one doubt that, what should be the total AUW (including all electronics ) n motor thrust relationship? I think the AUW should be half the total thrust (for 50 % throttle),please correct me if im wrong .


thanks for ur reply

hopping for more replies  (:|~

for trainer models... u dont need more thrust than AUW...coz most of the time forward movement and airflow around wing produces enough lift to make plane airborne...

more thrust is required if u plan to have 3D plane, and want to climb vertically straight....

i think for trainer, 70-80% thrust would be enough...again depends on airfoil...

hi ,
       Now im thinking about the following setup :

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8613
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=4318
http://www.hobbyking.com/hobbyking/store/__7301__Rhino_360mAh_2S_7_4v_20C_Lipoly_Pack.html
 
is it ok for me ??

please help me....
 
im expecting a good replies frm all of u guys

thank u ..!!

hi mate.
that looks a lot more in line with your model.
and far cheaper too ;)
regards
don

 thanks sir , u mean the setup is okk for my blu baby ??

hi guys where r u ?? im eagerly waiting for ur replies  (:|~

please help me ...  :help:

Data from motor page:

Max performance;
Voltage: 2S
Max current: 3.2~4.1A/20S
Prop: 6x3~7x3.5
Pull: 150~165g
For 150g indoor flyer.

This setup, although cheaper, will restrict you to planes with low AUW. If you plan to build bigger planes later on, go for more power.

hextronic 24 gram motor is good, you can try that if total weight of your model is around 350grams.

Hi Ashish,

I have also created Blue baby of 24" wing span from Bio foam.

electronics I have used as below :

AX 2308N 1100kv brushless Micro Motor
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=5429
Hobbyking SS Series 18-20A ESC
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=6457
Turnigy 1000mAh 3S 20C Lipo Pack
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9163
HXT900 9g / 1.6kg / .12sec Micro Servo
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=662
SF E-Prop 7x4 / 178x102mm
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9840

Total weight of plane is : 275 gram.
I tooked it's flight test last weekend but it was not very sucessfull
http://www.youtube.com/watch?v=yAC74M_rQ-IHere is a link of first try .

I tried two three times but results are same , It's taking a loop and diving on nose :(

Do I need to increes the size of plane , or please suggest changes I need for this or other sutable plan for this electronics.

@saurab -Thanks for opening up this thread I have same questions like you.


Thanks,
-Vinayak.

Dear Vinayak

You have a tail heavy plane. Typically the CG of the plane... i.e. if you put one finger from each hand below the wing at about 33% of the chord of the wing on either side of the fuselage (not touching it) in a calm ( no wind) atmosphere with all the gear you use for flying already loaded, the plane should remain horizontal. If this does not happen, you may have to change the positioning of the gear on the plane so that this happens... mainly you could try by changing the battery position more forward.

If still this does not solve the problem, just check  the axis of the motor. It should typically be pointing slightly to the right and slightly down to counter the natural torque roll of the motor.

From what I could gather from the video, you seem to have a typical case of 'tail heavy' phenomena.

Try, try and try again.. Also try to figure out thru your own thinking and analytical capabilities.... Do not give up. You have come so far.. you can do it

Best of luck ... don t forget to post your problem/ solution here in this forum

Saju

thanks to all for ur replies  :salute:

@ vinayak - actually thanks to u for sharing ur experience with us , but i must ask u that the electronics  u hav selected are okk for my 88 gms. blubaby ( without elecronics ) ?? or not ??

thank u ..!!

- saurab.

Hi Saju,

Thanks for your valuable reply  and encouraging words :salute:.  Definitely I am not going to give up and that’s why I’m here .(credit goes to RCIndia  {:)} )

 I will definitely work on your suggestions and let you all know.
But from above comments to Surbab  I am still not sure the electronics I have used is correct or this is for big plane or should I try same setup for BB32” or may be BB42”  ???

@Saurab: as you can see it was not my median flight, and I am also not sure about the electronics I would like you to go with expert advice. As some senior members Ashish , foamy and swapnil are suggesting here.

Thanks,
-Vinayak

Hi Vinayk,

i didnt get chance to see ur video as it is banned in my office!!!!! but all i could think of is...ur setup is little heavy...

as i mentioned earlier, for ur plane u only need 500-700 mAh 2s Lipo, even i used this battery on my 31" Phantom 210 with 24gm motor and it was pretty fast and gentle.
http://www.rcindia.org/electric-planes/modified-phantom-210-super-with-brushless-setup/

1000mAh 3s is pretty heavy for ur plane, i am using this battery in my 30" 3D yak. it will not be gentle and will not glide with less throttle.... u always have to keep throttle up to keep it flying....
even motor is powerful... and servos, u need HXT500.....and of course need experience person to fly it!!!!

As Suju suggested it could be CG issue and of course thrust angle...ur motor should have little down thrust..meaning motor axis should point little down.

as per my exp. if ur beginner then 24" size is not for u.. it becomes very sensitive to wind.....u need absolutely no wind otherwise.... even sometimes i struggle to handle my 20" plane!!!!
i dont mean to discourage u but, this is wat i learned from my mistakes.........

i will suggest to go for same model but with 30-34" WS and same setup...

keep it up and keep trying..coz flying is wat really matters...

cheers
Ashish

Dear Vinayak,
I made this plane long back and found no problem in flying.
Seeing this video i can assume below points:
1. The hand launch was not perfect. it was like a bump instead of a throw. Hand launch should be perfect for smooth initial flight.
2. i can even notice a sharp down elev. immediate after the bump launch, which lead to a loop and nose crash. after hand launch is given a slight down elev. is enough to take you bird into air.
3. Yes , CG is the biggest enemy and u can make it out of your own easily. just go through the build log of same. some where the CG points measurement is mentioned.
4. As said by Ashish, try to lower the weight of battery, rest specification is perfect.
Sandeep

hi friends ,
               Now im looking for this combo :

http://rchobbyaddict.com/product_info.php?products_id=123

http://rchobbyaddict.com/product_info.php?products_id=211

http://rchobbyaddict.com/product_info.php?products_id=98{5}27

is it good for me ??

thank u ...!!

- saurab.

motor seems good but will the motor take 3s battery!!!!!????

hi mate.
motor specs say 2-3s battery.
regards
don

I guess this set up should work ...looking at AUW of around 220-230 gms.I guess Its good enough...What about the prop? what size??

i wll go with recommended prop size for motor i.e. 8040 size

- saurab.

nice work saurabh... {:)}
i think u should work on the C.G of your model...
http://www.rcindia.org/tools-materials-and-building-techniques/building-tip-how-to-check-and-adjust-for-cg-of-a-plane/


wating for your next video... :thumbsup:
regards
tejas

thanks tejas , yeah n i wll definitely consider ur suggesion abt CG.

- saurab.