RC India

RC Models => Electric Planes => Topic started by: sanjayrai55 on August 07, 2013, 11:34:00 AM

Title: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 11:34:00 AM
 Quote "The original concept of the Ugly Stik was to design a radio controlled aircraft which could be built in an absolute minimum of time. Its purpose was towards a flying test bed for new proportional control ... which could be considered as expendable." Phil Kraft, the designer of what started as a plan in RCM magazine.

Another commentary:
This plane must be the most flown ever in RC. It comes in all sizes from two to ten feet in span. And all the variations that I have flown have been excellent. The original drawing by Phil Kraft does not seem to have been published. Perhaps he had no more than a few rigging lines and sketches when he started building. I expect he placed his radio control gear on the balsa sheets and installed bulkheads around them. The plans were drawn up for publication in Grid Leaks, I believe, and Jensen supplied kits. Dozens of variant drawings have appeared over the decades, not many of which improved on the original. Very shortly after the 60 inch span Ugly Stik came the 48 inch span Liddle Stik, and I still have the RC Modeler magazine from 1968 in which it was introduced. Graupner produced a kit for the 54 inch span Middle Stick which was beautifully prefabricated, and flew very well. I had one with an Enya 45, and can still remember the delight in finding that it grooved well in turns. It was my first aileron aircraft. I still fly a Stik, a version with 36 inch span, a 200 watt motor, and the exact same flying characteristics as the bigger versions. This design was right from the very start, and through Phil Krafts skill in aerobatics, nothing was overlooked. The cuteness and simplicity of the design allowed it to be taken up by many people who not have felt confident with the typical pattern model of the day. But this flew just as well, and still does.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 11:42:35 AM
My version is adapted from the plans in Spad to the Bone. I have (of course used Electric) modified only the Fuselage, leaving the Wings and Tailfeathers as per the original.

Having got some confidence in 2 mm Corro fuses after building & flying the Avispad, I used 2 mm for the fuse. Instead of ply reinforcement, I used 4 mm corro doublers, ply only being used for 2 formers under the wing, the Firewall, and the L/G platform. And yes, no yardsticks for the wing spar, 5 mm Corro doubled with a hefty Corro joiner brace. There is no Dihedral.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 11:49:36 AM
Specs:

48" span, 14" chord, 40" OAL, Turnigy 3542 1250 KV motor, 10*7 Prop, 3300 mAh Turnigy Lipo.

All-up weight is 1.8 Kg.

Wing top : 2 mm Corro
Spar : 2 X 5 mm Corro
Fuse : 2 mm Corro
Tail and Wing Bottom: 4 mm Corro
Formers and Landing Gear plate: 4 mm Ply
Firewall: 12 mm Ply
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 12:09:29 PM
The wing is straightforward, STTB gives a very clear idea on it's build.

I wanted a Trike Gear set-up, having broken a lot of props on tail draggers recently :D but am unable to get a 4 mm nose wire :(  (any help here is appreciated )

So I used something I bought from HK in my very first purchase from them, last year, when I just got into electrics. It's actually meant for a low winger, probably a jet, but I used the nose gear only.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 12:37:21 PM
The "plug" is for the plug-in wings. One side will be plugged in, the other side bolted

Made a "nut sandwich" with 2 nylon nuts and some wood, for the bolts to go into
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 12:41:15 PM
Wing bolt-down
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 03:27:27 PM
Two major challenges: the CG was designed for a 40 size glow. Despite my using a 2 mm fuse against the original 4 mm, and reducing the fuse to 2 1/4" square against the original 2 3/4, was still tail heavy.

Second was the motor....would the Turnigy 3542 1250KV be enough?
Title: Re: Spadstick - Electric (full size)
Post by: vishalrao on August 07, 2013, 04:09:22 PM
Nice build Sanjay sir! The bolt on wing is nicely done. Always wanted to try one but never got inspired enough. Will try it in my next build.

Keeping all the calculations aside, and since you already have the power setup in place, if the plane is raring to take off from your hand at full throttle, then you are fine with the power setup :)
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 07:15:28 PM
Thanks Vishal  :thanks:

Actually I maidened it this morning, and all my fears about power were groundless: it flies at half throttle!

I did do some corrective action on the CG though

Video follows later in this post
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 07:21:49 PM
The bolt-down wing does indeed make life easier - no more rubber bands  ;D

You could also put a balsa block shaped to match the aerofoil in the wing, between the spar and the LE, drill and glue in dowels. But I used a 4 mm ply plate in front because the balsa was soft, and I had doubts whether it would hold the dowels under strain.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 07:26:57 PM
Fuse glued up.

Nose wheel bolted, main undercarriage bolted.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 07:45:58 PM
Hatch uses a standard corro hinge and a canopy lock.

Calvin's views on Balsa are on all my Spads  :rofl:  >:D >:D
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 08:01:59 PM
To somewhat alleviate the CG issue, I changed the firewall and put on an extension motor mount
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 08:12:22 PM
Decor with Sign Vinyl
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 08:20:17 PM
Testing the motor: using a digital 'springless' spring balance & wattmeter
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 08:27:22 PM
The moment of truth has come! Maiden time.

I am too nervous to maiden my own builds, plus Girish Sarwal is a far better flyer than I. So he is the official Test Pilot  :giggle: ;) ;D
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 08:46:24 PM
http://www.youtube.com/watch?list=UUQhf5Pkzb8t7lzTwN0AIYEw&feature=player_detailpage&v=JNwPKMweT9A (http://www.youtube.com/watch?list=UUQhf5Pkzb8t7lzTwN0AIYEw&feature=player_detailpage&v=JNwPKMweT9A)

Many thanks to Maahin Beri fo taking the video

Need to reduce Aileron & Elevator throws. Otherwise she flies good - very sporty, as is supposed to be.

CG & Power were non-issues  ;D ;D
Title: Re: Spadstick - Electric (full size)
Post by: bmblb on August 07, 2013, 10:09:51 PM
very nice build ! Sanjayji.  :)
Title: Re: Re: Spadstick - Electric (full size)
Post by: arun.sreelakam on August 07, 2013, 10:23:05 PM
Again another great build from sanjay sir...
And this looks really awesome...
I felt a bit tail heavy in that video? Is it?
But really a superb build with perfection... hats off...:o::)

Sent from my Canvas using tapatalk 2
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 10:31:07 PM
Thank you "bmblb"
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 10:34:14 PM
Arun  :thanks:

Re. tail heavy, it was a maiden, and the trims are being set.

On take-off, we gave high throttle - not sure how much is needed.

You may well be right, but we will only know after the next flying session. Could only manage one flight because of the rain
Title: Re: Spadstick - Electric (full size)
Post by: K K Iyer on August 07, 2013, 10:35:13 PM
Sir,
Since she flew, the theory is irrelevant.
But this is what i was working on before i got sidetracked by visitors.
Minimum requirement
Wing loading about 16 oz/sqft
Stall speed sqrt of wing loading into 3.7, say 4x4 or 16 mph.
Cruise say 2.5 times stall say 40 mph or say 60 fps.
Or say 3600 fpm
Or 7200 rpm on a 6 in pitch prop.
On a 1250 kv this needs only 5 volts!

Another angle
Your motor is rated for max 45 amps, 665 watts, 1350 gms thrust.
Say 2 gms per watt.
For an 1800 gm plane you need say 900 gms thrust.
Or say 450 watts.
Or say 40 amps
Can your battery cope?

If you have checked power consumption and thrust, request you let me know,
As a test check on my estimates.
My guess was you need an 11 x 5.5
What did you use? 10 x6?

Regards to the only guy INTERESTED in really old stuff
Title: Re: Spadstick - Electric (full size)
Post by: K K Iyer on August 07, 2013, 10:41:31 PM
Still another angle
Need say 75 watts per pound of Ugly Stick.
Or say 300 watts.
Only 25 amps!

Thats why she flies!!!
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 10:58:50 PM
Iyer sir  :hatsoff:

But, your second calculation destroys the first  :rofl: :rofl:

In fact, she flies at about 200 W! And my battery is 3300 mAh. ie 3.3 X 11 = 36 W-hr, or 2160 W-min

If I indulge in extra hot flying, I will get about 7 minutes flying, normal flying about 9~10 minutes
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 07, 2013, 11:00:34 PM
As I mentioned in the beginning, I'm using a 10*7 prop
Title: Re: Spadstick - Electric (full size)
Post by: FlyingBrick on August 08, 2013, 02:30:57 AM
Great build !

Since you have already flown the model, please share your views on theoritical calculations vis a vis your practical measurements http://adamone.rchomepage.com/calc_motor.htm . How close are these ?

thanks !
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 08:00:33 AM
This software says my motor current is out of range.

See, the way I work it:

High winger sports model, so 75 W per lb = 300 W
Reserve power @ 20%, total power = 360 W

Motor with 10*7 prop gives 440 W

So I use this motor. In practice, the model in normal flight flies with ~ 200 W.I get 10 min flight time with 3300 mAh pack.

Actually measured: Flying time 3:51 minutes, battery consumption was 33% as measured.

Title: Re: Spadstick - Electric (full size)
Post by: vishalrao on August 08, 2013, 10:20:59 AM
Congratulations on the successful maiden. Very funny indeed :) Even I was expecting the motor to be underpowered. However, all's well that ends well  :thumbsup:
Title: Re: Spadstick - Electric (full size)
Post by: maahinberi on August 08, 2013, 10:32:05 AM
Wonderful build sir. I always like sticks  {:)} {:)} {:)}
When I come back, I may build this and put an O.S. 46 in it.
That would definitely be a screamer.  :P
Title: Re: Spadstick - Electric (full size)
Post by: VC on August 08, 2013, 12:19:13 PM
Sirjee, the way you are going, you will soon need another house to keep your models. Its getting to be a habit of admiring your masterpieces at such short intervals. Beautiful bird, as usual. Girish bhai.................. :thumbsup:
Title: Re: Spadstick - Electric (full size)
Post by: praveen on August 08, 2013, 12:50:23 PM
Pretty neat and nice build sir! :thumbsup:
instead of electric motor , you could have planned glow sir!
Title: Re: Spadstick - Electric (full size)
Post by: girishsarwal on August 08, 2013, 02:16:38 PM
It was amazing to maiden this. On the field, we just chanted a little and I gave full throttle. It just took off, less than 15 ft. In fact the initial climb was almost vertical so it is for sure not underpowered. And then to counter that we ended up overtrimming. Visibility was less so I lost orientation when the model was about 300m and it tumbled around a little before orientation was restored. Fun flying this model;

And nincompoops on the landing strip have their own definition of "I have a plane to catch"...:D:D
Title: Re: Spadstick - Electric (full size)
Post by: Mjet on August 08, 2013, 02:33:40 PM
Sanjay Sir, very clean and beautiful build {:)}

Title: Re: Spadstick - Electric (full size)
Post by: Rc Maker on August 08, 2013, 05:57:42 PM
Sanjay sir, i like your building skill (:|~ {:)} :hatsoff: superb finish :bow:
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:17:56 PM
Quote from: vishalrao on August 08, 2013, 10:20:59 AM
Congratulations on the successful maiden. Very funny indeed :) Even I was expecting the motor to be underpowered. However, all's well that ends well  :thumbsup:

Thanks Vishal

Actually, in my very little experience with electrics, what I have seen is a high winger, even a sports model, with a large wing area like the Spadstick needs only about 50 W per lb to fly. You do need 75 though, for take-off and mild aerobatics
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:19:38 PM
Quote from: VC on August 08, 2013, 12:19:13 PM
Beautiful bird, as usual. Girish bhai.................. :thumbsup:

VC sir, it's always a feel-good to read your compliments
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:20:53 PM
Quote from: Mjet on August 08, 2013, 02:33:40 PM
Sanjay Sir, very clean and beautiful build {:)}



Mohan...thanks so much! Time for you to start the Spadet again, only this time keep it light, light, light :D
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:26:57 PM
Quote from: praveen on August 08, 2013, 12:50:23 PM
Pretty neat and nice build sir! :thumbsup:
instead of electric motor , you could have planned glow sir!

Thank you Praveen. This model is actually meant for a 40 size glow! However, due to field problems, I prefer Electric nowadays. They are also more convenient, no starting paraphernalia, no mess to clean up :D
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:28:42 PM
Quote from: Rc Maker on August 08, 2013, 05:57:42 PM
Sanjay sir, i like your building skill (:|~ {:)} :hatsoff: superb finish :bow:

Thank you RC Maker
Title: Re: Spadstick - Electric (full size)
Post by: girishsarwal on August 08, 2013, 09:36:40 PM
VC sir, thanks for the thumbs up. I didn't do much though. The build speaks for itself. The stick flew on its own once it was trimmed.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:37:27 PM
Quote from: girishsarwal on August 08, 2013, 02:16:38 PM
It was amazing to maiden this. On the field, we just chanted a little  

And nincompoops on the landing strip have their own definition of "I have a plane to catch"...:D:D

Girish: Those were not chants, they were magical mantras of great power :D :D

To manage crowd control, we will keep a mascot: a huge dog - Great Dane seems good ;D
Title: Re: Spadstick - Electric (full size)
Post by: girishsarwal on August 08, 2013, 09:43:40 PM
You're feeling so German sir! nicht?
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 08, 2013, 09:47:20 PM
Jawohl!  :rofl:
Title: Re: Spadstick - Electric (full size)
Post by: vishalrao on August 09, 2013, 09:15:31 AM
Quote from: sanjayrai55 on August 08, 2013, 09:37:27 PM
To manage crowd control, we will keep a mascot: a huge dog - Great Dane seems good ;D

:giggle: Ha ha ha. That's an excellent idea. Sure will keep bystanders from touching and messing with the models.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 09, 2013, 09:30:29 AM
(http://www.debiwolfreeves.co.uk/wp-content/uploads/2012/10/Dog_attack21.jpg)

Flew her again today after reducing throws. A sporty model is a sporty model. Flies smooth and fast, even at less than half throttle. Very responsive to controls.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on August 09, 2013, 09:34:05 AM
Maahin   :thanks:

If you are going to build it in Nitro, use a 4 mm Corro fuse.
Title: Re: Spadstick - Electric (full size)
Post by: girishsarwal on August 09, 2013, 10:22:01 AM
Someones getting the run of his life, for his life...farhans next movie plot is ready
Title: Re: Spadstick - Electric (full size)
Post by: avinvarghese on April 26, 2014, 01:36:54 PM
I would like to get suggestion regarding the electric parts  for SpadStick (http://spadtothebone.net/SPAD/SpadStick/) that i am  building. Currently i have the following parts with me.

propeller I am going to place

Master Airscrew propeller 6x4  (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=8009) OR TGS Sport 6x4E Precision propeller (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7936)

Motor

NTM Prop Drive Series 2836 2200kv (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=21481)

Battery

Turnigy nano-tech 2200mah 3S 35~70C Lipo Pack (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=11944)

Should i go with this setup or can anyone Please suggest another.

Thank you.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on April 26, 2014, 01:48:26 PM
This model was originally designed for a 40-46 size engine, ie about 750 Watts+

When I built it, I really worked on reducing the weight, and got it to about 1.8 Kg, against the original 2.5 Kg ++

Thus it would need a motor of at least 1.5 Kg thrust, not being a trainer but in fact a sports model. Going by the usual norms of 125 Watts/lb for the sports model, you need a motor of about 500 W. Looking at the size too, a prop of minimum 10*7 is needed, with 11*7 preferred

The proposed NTM motor and it's recommended prop will give nowhere near the kind of thrust needed. In fact with the battery you propose, you will get only about 600 gms of thrust, that too at full throttle! The model will not fly.

You need a lower speed, higher torque motor. I used a 3542-1250 KV I think, and it was adequate with a 10*7 prop, and 60 A ESC, giving me about 7 minutes normal flying on a 3300 mAh 35-60 C Lipo

I am not trying to dissuade you, but remember, heavier models need higher torque motors; high speed motors are better suited for light fast models like jets typically

Title: Re: Spadstick - Electric (full size)
Post by: avinvarghese on April 26, 2014, 02:01:56 PM
The electric parts i mentioned above was actually brought for Axon FPV (http://fpvlab.com/forums/showthread.php?5230-Axon-FPV-Basic-Scratchbuilt-Design). I will go for lower speed, higher torque motor and other parts mentioned by you for SpadStick (http://spadtothebone.net/SPAD/SpadStick/). @sanjayrai55 Thank you.
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on April 26, 2014, 07:20:47 PM
Welcome. Good luck with your build  :thumbsup:
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on June 19, 2015, 08:01:17 AM
Decided to convert this to Nitro

Using an ASP 32. Changed the nose gear too, and the horizontal stabilizer which was unwell  :P. Using a 4 mm Spring Steel nose gear which I got made from a commercial spring manufacturer

(http://s25.postimg.org/p94mgidz3/20150619_074130.jpg)

(http://s25.postimg.org/e89hbhlq7/20150619_074143.jpg)
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on June 19, 2015, 08:03:15 AM
240 cc tank - should be good for about 20 minutes flying time once the engine is fully run-in  >:D

(http://s25.postimg.org/burjkh7b3/20150619_074541.jpg)

(http://s25.postimg.org/smcv387jz/20150619_074550.jpg)

(http://s25.postimg.org/5sjwtziv3/20150619_074634.jpg)
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on October 22, 2017, 05:17:30 PM
Still going strong

https://youtu.be/vG9HwhsJJX8
Title: Re: Spadstick - Electric (full size)
Post by: sanjayrai55 on October 10, 2018, 06:01:18 PM
Gallery

https://postimg.cc/gallery/1tzus9lgs/