@KK
What have you used for doping the parts?

Being more in indoor ultralight rubber -- have never needed doping ..
Regards

@WeekendFlyer. Thanks and you are welcome.

Looking forward to everyone's photos and videos.

I see everyone is building. So yesterday I made a trimming video even though it was very windy. You should do all your trimming , glide test etc.  in no breeze conditions, probably late evening.

Anyways, this is a raw video. But I have tried to explain all the key concepts.

Once you think you are ready for the catapult launch, play with the launch and bank angle. One combination of the launch and bank angle will be correct for your glider. I cannot predict it for you are myself either. This is called trimming.

Video Error: in the bank angle, I kept saying 45 degrees, but did a 90 degree angle. Sorry, my error as I was trimming the second glider at that time. So try a 70 degree launch angle and 45 degree bank, not a full bank as shown in video.

PLEASE ASK QUESTIONS. I have gone over the basics in the build and trimming. But when you ask questions, I can hopefully answer them and you can start enjoying the CLG.

You have got an EXCELLENT kit from Mr. Iyer. As they say, I fully suspect that your glider from his kit will fly right of the drawing board.

Quote from: Glidiator on November 08, 2020, 07:29:38 PM
What have you used for doping the parts?
Being more in indoor ultralight rubber -- have never needed doping ..

Once upon a time in India you could get Dope from India's Hobby Center

Thereafter, NC Clear Lacquer, usually Duco, from car painters.
The key is to use Duco NC thinner, not hardware store thinner, which is apparently methanol+water!

Ok , thanks for the video . So for a hand launch , are these (same) angles that should be followed ?

@SI74,

In case you haven't seen my Aug 2018 post in the '1st Chuck' thread, here's a copy:

On reaching the second test of Chuck Glider flying,
Having crossed the first test (finding an approximate CG and getting a smooth glide of 30-40 feet, without stalls and dives). You did pass that test, no? Else you return to stage one!

The second test, or stage, is how to avoid looping in a full power launch.
This has two parts
How to launch
How to avoid looping.

The launch for the first stage is from shoulder height, model held just behind the CG, nose pointed slightly down, aimed at a spot on the ground about 50' away, and pushed gently straight, without your hand describing an arc.

The power launch is utterly different except for holding the model at the same place, ie, just behind CG.
(I'm assuming you are right handed)
Hold the model lightly.
Keep your wrist loose. Don't cock it.
Swing your LEFT hand up about 45degrees, while swinging your RIGHT hand down as low and as far back as you can.
Are you holding the model loosely? Is your wrist loose and not cocked?
If so, the model should be banked RIGHT A LOT MORE THAN 90 degrees and pointing UP ~45 deg.
The action is like a discuss throw.
NO ELBOW BEND. ALL JOINTS OF RIGHT HAND LOOSE, FROM SHOULDER TO FINGERS.
Stand facing the wind, wind up your torso till your left hand points into the wind and 45 deg high.
The right hand will be more than 180 deg away, behind your back.
To launch, swing your whole upper body hard left, release the model when your right hand is about horizontal. At release the model should be banked right about 45 deg and pointed up about 45 deg, and going a little to the right of the incoming wind..

This is the way to launch, and enter the second stage of how to cure the looping!

Ok , got it . Thanks.

@SI74,

How to cure looping in full power hand launch

Since it is premature to discuss this on this thread, I've sent you a PM.

Will discuss on this thread later, after everyone has crossed the test glide stage...

Quote from: K K Iyer on November 08, 2020, 09:39:17 PM

Quote from: Glidiator on November 08, 2020, 07:29:38 PM
What have you used for doping the parts?
Being more in indoor ultralight rubber -- have never needed doping ..

Once upon a time in India you could get Dope from India's Hobby Center

Thereafter, NC Clear Lacquer, usually Duco, from car painters.
The key is to use Duco NC thinner, not hardware store thinner, which is apparently methanol+water!

Thanks. Will try that
Regards

Just popped by to see how things were and the first thing that I see is this beauty of a thread!

@VC,
Welcome back.
Nearly 2 years since your last post.

See the 'Next Contest' thread.
Look forward to your entry as an honorary participant with your Flika perhaps?
Or maybe there's even a Lunchbox in your fleet...

Warm regards

A few very short videos of test gliding the Lunchbox...

Got a surprise today.
A participant was unable to get his test glides right.
Because he was trying for 10 seconds, not realising that the test glide is only meant to get the model flying correctly

I think this is a result of too many instructions too soon.

And is the reason why no test glide posts are coming.

Please, folks, do your test glides, and get it to fly 20-30ft straight with no climb or dive, and maybe a slight turn.

Please see my test glide videos, and copy.

Yes, I too thought so initially! That was why I repeatedly asked how to do a hand launch ! I too was looking for 10 sec flight during test glides ! Thanks Iyer sir for the correction.

Yes, there are three separate stages.

1. Test glide from shoulder height, slightly downwards and not fast, to a point 20-25 ft away on the ground. Flight time 2-3 seconds. Please see my test glide videos.

2. Full power handlaunch, for those want to take advantage of the multiple allowed (10 second hand launch equivalent to 20 second by catapult). Instructions below (*)

3. Catapult launch (see instructions/videos by Freeflight)

* Hand launch
I'm repeating contents of an old post on my '1st Chuck' thread.

The launch for the first stage is from shoulder height, model held just behind the CG, nose pointed slightly down, aimed at a spot on the ground about 50' away, and pushed gently straight, without your hand describing an arc.

The power launch is utterly different except for holding the model at the same place, ie, just behind CG.
(I'm assuming you are right handed)
Hold the model lightly.
Keep your wrist loose. Don't cock it.
Swing your LEFT hand up about 45degrees, while swinging your RIGHT hand down as low and as far back as you can.
Are you holding the model loosely? Is your wrist loose and not cocked?
If so, the model should be banked RIGHT A LOT MORE THAN 90 degrees and pointing UP ~45 deg.
The action is like a discuss throw.
NO ELBOW BEND. ALL JOINTS OF RIGHT HAND LOOSE, FROM SHOULDER TO FINGERS.
Stand facing the wind, wind up your torso till your left hand points into the wind and 45 deg high.
The right hand will be more than 180 deg away, behind your back.
To launch, swing your whole upper body hard left, release the model when your right hand is about horizontal. At release the model should be banked right about 45 deg and pointed up about 45 deg, and going a little to the right of the incoming wind..

Please ask all the questions you may have. Enjoy flying the glider and best wishes for the contest.

I am yet to fix the CG, but here is a time lapse of the complete build process. Will share proper build video soon.



Sent from my AC2001 using Tapatalk

My glider is almost ready. 
However, it seems tail heavy, will have to put more weight on nose to balance it.

Any suggestions ?

Quote from: WeekendFlyer on November 14, 2020, 04:22:21 PM
My glider is almost ready. 
However, it seems tail heavy, will have to put more weight on nose to balance it.

Any suggestions ?

Obviously so, as there's more wood behind the CG than ahead of it 

That's why plasticine was included for nose weight!

If I put more plasticine the overall weight will increase.
Please guide me. 

@Weekend Flyer. Will not increase by much. CG is very vital to make it fly.  I had a Lunchbox at 8 grams, no issues in a good flight.

Great photos and videos. Enjoyed seeing them. More to come,  I hope.

Quote from: WeekendFlyer on November 14, 2020, 06:08:22 PM
If I put more plasticine the overall weight will increase.
Please guide me. 

It's not extra weight, it is necessary weight.
Can't fly till it's balanced.
Please put plasticine on the nose till it balances at 1.75" behind the leading edge of the wing.
This is the starting point for the CG.
As you do test glides, the nose weight may need to be increased/ decreased slightly.

1. Please balance as suggested.
2. Please test glide as suggested. These will last 2-4 seconds only. They are not full hand launches.
3. See my test glide videos, and copy how I launch, with the nose pointing down to the ground about 20-30 ft away, and slow enough to avoid climb at launch.
4. See test glide videos of Hitesh Kher and Karthick. You'll have to share your phone number with them to see their videos on Whatsapp

@Weekend Flyer brought up a good point to discuss. the topic is Wing Loading.

Wing Loading = Weight of glider in grams divided by the wing area in Square inches. For almost all free flight models , one needs to build light so we are below 0.5 grams per square inch. The experts here go to 0.4 grams per square inch, but not lower than that for outdoor planes.

A very rough calculations on Lunchbox gave me 13 square inches of it's wing area. Please someone check my estimate, I could be wrong. So at 8 grams it gives 0.6 grams per square inch of wing loading. Not too far, for a first time builder, pretty good.

Another point, start with CG location shown on the plan. That is where the designers recommends to begin with. My two Lunchboxes, one is right at the location, other is a 2.0 mm ahead of the shown. You have seen my videos. Both fly well.

Use the technique Mr. Iyer suggested and get the glide correct. See his videos to make the point clear. You may then have to add or subtract clay to get the glides he shows.

Looks like Mr. Iyer and I had same thoughts, posted together. Nice.
Would love to see your videos. Can you guys post it on YouTube? Or can we make a WhatsApp group. Call it "ILC" : Mr. Iyer's first Lunchbox  glider contest for beginners in IN.

@KK Iyer: Thanks for all your instructions.  I have flown towline glider and have idea about the glide test.  I think it is more or less same with chuck glider.  Will go thru the test glide phase tomorrow.

@Free Flight:  Thank you.  I have built (to say correctly, "assembled") this chuck glider, not only this, a chuck glider for first time and this was just a sort of challenge for myself. But its good to learn new skill.  But more important is that the guidance ("that too FREE") we are getting thru this forum.

Thank you all.

Did some test glide of my glider.  But the flights were in afternoon and also, there was little breeze, which was affecting the glide. 
So postponed the test glide till evening.
Sorry no videos captured, as I was all by myself.

The glider was flying well and am getting flight time of 2-3 seconds but its banking right.

Will try out after warping the rudder / fin a little bit in the opposite direction.

See you later !!!