INDORE BIPE - A model for newcomers

Started by K K Iyer, March 21, 2014, 03:45:19 PM

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SI74

Thank you sir for the encouraging words. Feels proud that I made you happy .

pnkyjs

such an amazing build, an great flying , just lucky to see this thread today
V911
V977
XFX 450 V2
Scratchbuild foamies galore

K K Iyer

Thanks for bumping this thread.
With the proposed regulations, this may be the only type of RC airplane that we can fly in cricket fields!

taksh

I am interested in making this plane as my 2nd plane.
So, this provide plans. K K Iyer sir said "there is no need of plans" but i am new & build only one plane which never fly. So, please provide plans.
@SI74  you said 1600kv motor but not more size. Tell me motor size.


K K Iyer

@taksh
If you look at all the pics, you will find that a ruler was placed alongside.
So the measurements of the wingspan, wing chord, dihedral, tail span &chord, fuselage length/width, angle of incidence of the wings are easily visible.
To say that it can't be built as there are no plans, is a lame excuse.
There is enough data in the thread to build this model.
But only if you have obtained one sheet of depron. Don't build it with thermocol!
Just look at the pics carefully. You'll find everything you need.

docsree

@ KK Iyer sir, your in box is  full. Not able to message/ communicate to you.

Ajay Sarwan

Quote from: docsree on September 04, 2018, 09:07:14 PM
@ KK Iyer sir, your in box is  full. Not able to message/ communicate to you.
I apologise for that. It is because of me :)

K K Iyer

Quote from: Ajay Sarwan on September 04, 2018, 09:22:52 PM
Quote from: docsree on September 04, 2018, 09:07:14 PM
@ KK Iyer sir, your in box is  full. Not able to message/ communicate to you.
I apologise for that. It is because of me :)

Not at all.
Just exchanged half a dozen msgs with docsree, anew contact.

My inbox is sometimes full because I delete only 1-2 msgs out of 1000!
BTW, did you see the Indore Bipe thread, revived after nearly a year?
You may find it of interest...

Edit
Oops. It is this very thread!

Ajay Sarwan

Oh yes.
I have half a board of depron too. My Hand itches to start building one but I am controlling.
I Need to master chucks before RC.

K K Iyer

Quote from: Ajay Sarwan on September 04, 2018, 10:09:59 PM
Oh yes.
I have half a board of depron too. My Hand itches to start building one but I am controlling.
I Need to master chucks before RC.

If your depron is 3mm or more, please build this bipe at once.
Don't worry if you don't have the carbon tube spars.
I'll tell you arecanut alternatives  ;D

taksh

Quote from: K K Iyer on September 04, 2018, 10:21:06 PM
Quote from: Ajay Sarwan on September 04, 2018, 10:09:59 PM
Oh yes.
I have half a board of depron too. My Hand itches to start building one but I am controlling.
I Need to master chucks before RC.

If your depron is 3mm or more, please build this bipe at once.
Don’t worry if you don’t have the carbon tube spars.
I’ll tell you arecanut alternatives  ;D
then plz tell me Alternatives for balsa? i think icecream sticks will work.

K K Iyer


K K Iyer

@taksh,
@ajay sarwan,
Please take a look at M2024 1600kv from RC Bazaar.
This is the cheapest suitable one I can find ~Rs600, in stock.
As per the data table, with a 7x3.5 prop, a 2s 500mah lipo should easily give you 6+ minutes.

http://rcbazaar.com/product.aspx?productid=4091

taksh

@K K Iyer
I have 500mah 3s lipo. I need motor for 3s.
Please suggest motor for 3s.

Ajay Sarwan

@taksh
Go the link and read the load test report on the page.
3s is 11.1 voltage.

Ajay Sarwan

I built the Indore bipe with recycled coroplast.
It's AUW is 360 grams, 80 grams heavier than depron bipe built by KK Iyer.
I tried drilling holes in fuselage to reduce some weight. But it did not help much.




Now I have some issues with motor.

Motor specification:
Motor: Avionic M2226/25 KV1800 MICRO brushless motor
KV (rpm/v): 1800
Power: 69W
Winds: 25
Resistance: 657 mOhm
Idle current: 0.5 A
Weight: 21gms

Combination of usage:
PROP - 6x4 E
● Get  200  gms Thrust
Lipo - 2 cell 7.4V
ESC - 20 amp

PROP - 7x3.5 SF
● Get  300 gms Thrust
Lipo - 2 cell 7.4V
ESC - 20 amp

PROP -  8x3.8 SF
● Get  500 gms Thrust
Lipo - 2 cell 7.4V
ESC - 20 amp


I have both 6x4 and 8x3.8 props.
And I use 30 Amp ESC, and 2 cell lipo 1500mah 25C.

I feel 6x4 does not produce enough thrust,
and when I put 8x3.8 prop, the motor jitters and does not spin.
At full throttle, the servos also jitters.
Is it because of faulty receiver or loose connections?

K K Iyer

Colourful interpretation of the original!
See post 46&48 for equipment used by SI74 (an expert in flying in a really small area!)

This bipe is not designed to glide, as you found in your test glides!

Now an 1800kv motor (or 30rps per volt) is 240 rps on 8v.
Or 80fps on a 4" pitch prop.
Or about twice twice as fast as required, hence inefficient.

Your query was whether to try to fly it with the 6x4, despite apparently inadequate thrust.

My recommendation:
Go ahead with your 69w motor, 6x4 prop, 2s lipo
1500mah lipo and 30a ESC are far too much, but doesn't matter.

The trick is to hand launch (level) as if you were test gliding, with the throttle about 50%.
This allows you to cut power if you see any problem.
And allows you to increase power and climb if all seems well...


Ajay Sarwan

thank you sir.
I checked the electronics now, and the servos go crazy at the top of throttle.
I will make a video and upload it tomorrow.
It will be easy to diagnose the problem.


THE RC GUY

sir have you designed anything similar in the recent years?

K K Iyer

Quote from: THE RC GUY on June 18, 2020, 09:51:39 PM
sir have you designed anything similar in the recent years?

Yes. But that's another story.

Saw from your post in the Sales thread that this Indore Bipe may interest you.
The original was taken away by an old friend, but I can easily make a copy.

If necessary, I can send everything needed to fly except for 30 minutes charging (though sending Lipos is not possible via Post Office)

But you may not need everything ready to fly, as you may already have some stuff (or most of it)

If you wish, you can say what you have (pl include specs) and what you need.

Regards


THE RC GUY

#70
i really like your design sir and cannot express how happy i am to see this reply
and yes sir i do have some of the things


THE RC GUY

I have pm'ed you sir
please reply whenever possible

Regards
Nitya

K K Iyer

Hi everyone,

Hard to believe it's almost 10 years since I built this bipe, flew it, and gave it away.

Last fortnight I got a call from a member who had met me years ago, asking about depron for a trainer. I referred him to this thread, and offered to send him a kit, using the last of my 6mm sheet.

It took me a few days, as nowadays I work really slowly, and only as and when the mood strikes me.
Since the sheet was 26" wide, I made the top wing 26" span and the bottom one 22" (instead of 24" each).
Then made semi span spars out of coffee stirrers instead of CF tube.
And dihedral braces out of 1mm fibreglass sheet instead of cycle spokes.
Checked out a small motor lying unused for 17 years (!). Gave over 150 gms thrust with a 6x4 prop at 4amps/45watts. Enough for a sub 300 gm trainer. Though an 8x4 on 2s would have been more efficient.

Put it all in a box (that took me a long time to make!) and sent it away.

The next night I received a nice pic of the completed model.


sanjayrai55


pnkyjs

V911
V977
XFX 450 V2
Scratchbuild foamies galore