Hi,
Tried Building a mini hlg for the challenge posted here.
http://www.rcindia.org/kites-trains-free-flight-and-all-others/one-minute-flight/
It was a quick build.(Took an hour and a half )
Specifications:
Material- 0.75mm Balsa
WS- 9inches
Weight- 4g

Polyhedral wing followed by the construction of tail section.

0.8mm CF rod used for fuse stick.

@ kiran rc,
Outstanding work, as expected from you!

If 4gms AUW is correct, its a real achievement. My 9" HLGs are in 9-10gm range!

You said you used 0.75mm balsa. I can see that the stab, fin and pylon look like 1/32", or 0.75mm.

But the wing?
From the airfoil shape and a close look at the thickness of the left tip in the first pic, the wing seems to have been carved from 2 or 3mm balsa, and not curved from 0.75mm sheet.
Which one is it?

Your balsa stock seems to be of contest quality (6lbs/cuft or less). Where did you get it?
Can you weigh one of your sheets and tell me?
(6lb/cft weighs about 10gms per 1mm thickness in a 100mm x 1000mm sheet)

BTW, the wood grain for the pylon needs to be vertical, not horizontal. Reason will become apparent when you try a full power throw 

Await test flight video...

@K K Iyer
Sir, the wing is curved from 0.75mm balsa. (Soaked with warm water and then heat treatment)
I got the balsa sheets from Aliexpress. The stock are mixed up with both A/B grains. Single sheet of 250mm*100mm weighs about 1.8-2g.

Excellent purchase.
If your weight data is correct, it means you are getting A/B grain 5-6lbs/cuft, which is contest quality.
(We can discuss C grain privately...)
Gives you a big advantage in this challenge.
Most of mine is 50% heavier.

Would you care to post a few hints on the 'One minute challenge' thread for the benefit of the other entrants?

More specifically, can you guide Taksh on that thread?

Thanks

Quote from: kiran rc on May 27, 2018, 09:01:40 PM
@K K Iyer
Sir, the wing is curved from 0.75mm balsa.

From the first pic looked like top carved from 2-3mm with flatbottom...

I guess this is the pic you are referring too. The shadow makes it look like having a carved aerofoil. The fact is that I've slightly curved the edges to make a good joint between the pieces.