combatpigg

My Feedback: (3)

Me and a co-conspirator were talking about interesting projects and the subject of Competition Fun Fly planes came up.
I built one years ago that was so much fun.... a guy bought it off me at the club field before I could get it trimmed out.
There is an AMA rulebook category for these planes and they were / are capable of some stupendous things.
Any guess what the record is for touch and goes in a minute...?

It looks like I "missed the mark" with this plane to be powered with a ASP .12.
It's going to end up too big / too heavy, but I'll try it like this before swapping a .15 onto it.
Gotta shift gears mentally and get into the frame of mind that the plane will be powered with a .061...then a .12 will be just right for it.

longdan

Looks very cool, but the real test of a 3D plane is its hover and vertical ability. It will be interesting to see if the ASP .12 is up to the task.

combatpigg

My Feedback: (3)

I think it will end up too heavy for the .12

If the .12 can turn a 7x3 15,000 rpm, then it will put out 26 ozs.

A good hovering plane for a 7 inch prop needs what sort of thrust to weight ratio..and what sort of throttle response...?

longdan

After some complicated differential calculus I have worked out that it will just hover with a thrust/weight ratio of 1:1

combatpigg

My Feedback: (3)

At 1:1 I don't think you can sustain a hover in the real world outdoors with a 7 inch prop. My open frame PBF for Norvel .074 power has almost 20 ozs of thrust and weighs about 11 ozs.
With a 7 inch prop it isn't a very easy plane to maintain a hover with at that weight.

hogflyer

CP,

I like the sewn hinges for the elevator. Looks like it'll be a lot of fun to fly.

Hogflyer

airraptor

My Feedback: (66)

where did he say he wanted a 3D plane. Its a fun fly plane lol most people think there only three types of planes, 3D, speed and slow scale lol.

CP I also built a plane like that for "fun fly" it was 225sq with a thin 12% airfoil. The fuselage was made to fully enclose servos and r/c stuff. I got the plane to 18 OZ with a queen bee (lol). It flew just lke my larger yardstick (very fun fly like). I kept the airfoil thin to help with the thrust issue.

Believe it or not the MA 6x3 and 7x3 were best for hovering type thrust over the APC since the MA were about an inch less in pitch.

CP if you would like some idea's on how to loose an ounce or so on that engine and upwards of 2-3 ounces on the plane let me know with a PM

combatpigg

My Feedback: (3)

I'd like to know your ideas for losing weight but you should be able to share them here...?

I'll probably try it on bladder with the bladder mounted outside the plane. That saves the weight of the 2 oz tank, no muffler, no throttle servo, etc.

The spars collectively could be shaved, but a big pile of shavings might only add up to.....
Smallest possible battery
Remove the RX case
Smallest servos possible
Convert engine from ball bearing to sleeved
Carve as much steel from the crank and aluminum from the case as possible
Use pull / pull linkages...or hair thin music wire with lightweight guides.............

All this stuff is great, but some is high maintenance, prone to failure, or just not worth the effort to me.


This is 20 ozs of thrust on a 11 oz plane. http://youtu.be/Wq9vd5ja-gw

flyingagin

you always got something interesting cooking

airraptor

My Feedback: (66)

no motor mount, shave off the engine aluminium mounts, grind down the carb as much as you can (outside of it), machine down the prop hub to fit the smaller apc props. drill thru the crank from the front with a drill bit mounted in a drill press. some cranks can be drilled farther down the the middle in the inside and then add JB weld or equal type epoxy, use aluminum nut and washer for holding prop on. to mount the engine mount them like the Q-500 planes are. just take the back cover off and use it as a drill guide. get longer bolts/screws to go thru the firewall, thru back cover and screw into the engine.

Use aluminum screws where you have steel and use nylon where you have aluminum now.

dont use servo mounts in the fuselage just use servo tape. if you dont want to use a bladder tank use a regular tank but use aluminum fuel line. if not going to fly upside down then extend the aluminum fuel tubing at a down ward angle to the back of the tank with no clunk. if you need to kill the engine just fly upside down for a sec.

if trying to save even more weight use pull pull on the elevator with 5-10 kevlar fishing line, 1/16th ply horns glued to the elevator.


bunch more Ican add later.

combatpigg

My Feedback: (3)

Those are some pretty great ideas..!
The idea to use aluminum screws is scary...I would think that they are pretty easy to strip or break...?
Shaving off the mounting lugs is a "Leap of Faith". I would test my firewall mount before commiting to hacking off those lugs.
Hacking off the crank's snout and drilling it for aluminum prop mount hardware....seems like you need to detemper the crank before doing the machine work...?

alcarafa

Try this one is only 1.4 oz
http://www.hobbyking.com/hobbyking/s...ever_Pack.html

airraptor

My Feedback: (66)

This one is only .50 ounces and can get down to .40 if you solder ona thinner wire. just use a regular 3" or 6" extension, old broken servo or what ever and cut wires off and solder new ones on. to easy.

http://www3.towerhobbies.com/cgi-bin...?&I=LXYXA6&P=0

Crosscheck

Hi CP,

Some box I have, has old nylon (yellow/Tornado, white/TopFlight), 7-4 props. When you boil them in water to 'relieve' the molding stresses, they get soft, and 'de-pitch' at RPMs...

A cut down 8-3 might be your best bet.

Somewhere, I have seen a 2-Pitch prop.?

Great Projects CP...

Speed Records on the Salt Flats..

Then, climbing Mount Everest ! ! !

Makes me realize,, I am not the only one,

Who likes running/flying small engines in model airplanes.



Thanks, CP

Take care,
Have fun,
Dave'crosscheck'Falllowfield
Maac 6437
Unabashed Combat Team

combatpigg

My Feedback: (3)

Dave, those were great props for the Jr. Satan / Fox .15. I don't know if I have any left.

Rafa, thanks for the link to that battery. It looks like a good one.

skaliwag

My Feedback: (1)

How about this for $5. and 11.5gms

http://www.hobbyking.com/hobbyking/s...mpatible_.html

combatpigg

My Feedback: (3)

The 200 mah LIFEs look good.
The charger looks like it just has a 3 position switch...?

Prop_Washer2

My Feedback: (26)

Where can I get some of those "Blue Hinges"..??? 

alcarafa

Wowwww you can buy seven batteries at HK for the price of one @ TH [X(] .
I've used HK LiFe Batt's for long time without problems

Sessholvlaru

You should extend the ailerons inboard so that they are in the prop blast. That would greatly help low speed handling during aerobatics.

eddieC

My Feedback: (2)

I love fun-flys, but not so small. I have a Coal Hauler with Webra .32GT to put together soon.

The bird is the word...

combatpigg

My Feedback: (3)

You have the classic combo from what I hear. I think a 8x6 prop will give it tight looping ability.
When you finish it, name it Surfin' Birdo.......[8D]

combatpigg

My Feedback: (3)

Funny how I figured just the opposite would hold true.
Remember that the object to fun fly planes is slightly different than freestyle 3D. With fun fly you try to see how many loops you can do in a minute and touch and goes...which are inside loops that you bounce off a nose wheel.
I'll cover these ailerons seperate from the rest of the plane and pin the hinges [no glue] so I can try full length ailerons later.

phatboy

Your a mad man CP. Just whippin planes out like that. lol

combatpigg

My Feedback: (3)

I'm just trying to build my resume so I can possibly get a job at a Chinese ARF sweatshop.