Ok...so the Ryobi will put out what? 12lbs thrust or so?
With CH ignition it's around 3lbs motor weight.Maybe a bigger throat carb?..add radio, batteries, airframe.....can it be done under that weight?

Good question to ask would be....what kind of airframe could a person build Scratch. To get a Ryobi to hover without the airframe rattling itself apart?

What would be the ideal weight of an airframe with servos/battery installed to meet the 1:1 thrust ratio?

Recommended servos? Battery sizes? Max airframe weight?

Has it been done? I'm thinking the new two-ring version might actually be able to??

Just something to think about..... to make a giant scale 3D machine for less than 200 buxs (with engine).

Now THERE you'd have a VERY popular plane.....

Any ideas?

High Flights
CrazyHerb

You will need to measure what actual thrust you can get from your Ryobi. Use fish scales.

You will need a plane + engine that is somewhat less in weight than the thrust produced. Use fish scales

Something like a sturdy 60 size plane with the firwall back 2 or 3 inches.

Jim

Jim,
Excellent points!
I would also add that you'd need a decent amount of wing area, say 1000sq in to start.

Maybe use the new Stinger 120 ARF as a starting point to scratch...I've heard of an RCS 1.40 on a U-Can-3D...

You'd have to do some serious mods to get it light though..

I don't want to get too far off on the Design aspects of the airframe....as interesting as I find Design...(I can start a "design" thread in that forum) MORE OF the simple idea of getting a Ryobi to hover and IF it's actually been done.

CrazyHerb

If you want to hover, put the Ryobi in a heli. Zenoah has a heli version for the G23, so a Ryobi would give comparable power.

World Models's Fun World 3D might be a good candidate for 3Ding a Ryobi, but I still don't see the point of the exercise. By the time you add an electronics ignition, which would be mandatory if you gonna try to hover, the engine alone would burst your $200 ceiling.

Good Call Volfy,

$200 bux gets you hardly anywhere in Giant Scale.
Lucky to get a Ryobi on electronic ignition for that amount.

Trimmer - $70
CH Ign w. Hub - $120
Battery - $15
Kill Switch - $10

Sitting at $215 For motor....no prop..I'm not saying $200 is the ceiling...so with that understood....where are we?

Anyone got good weights on radio equip?

I'm thinking needs to be like 4-5lbs (covered aiframe alone).

CrazyHerb

After you make the conversion, you might want to consider a prop for openers.

The "rule" is about 1.5x thrust to weight ratio. So you are going to need a 4lb plane +3 lb engine + 1lb radio.
Build in lots of lightness

If the Earth had the same mass as the moon, you could hover a 40% AW Edge with the Ryobi.

What other problems can I solve for you today?

my balsa nova 120 is only 10.5 lbs with a us 35 so I think a ryobi is up to the task of actualy pulling out of a hover wityh this airframe.

Darin

Your best chance is probably an open truss framed fuselage and a built-up wing with no sheeting - kinda like a Sig Kadet Senior with a symmetrical wing. Use Econocote to save weight.

Come to think of it, my WM Super Stunt 60 could probably have been built to be less than 4lbs airframe.

You can save weight with Lithium Ion battery packs, but you're stuck with standard sized high-torque servos if you want to 3D.

I think the standard answer project engineers have for their manager applies to this:

I can make it high performance,
I can have it done fast,
I can do it cheap.

Pick any two of the above.

Man....that's good.....I've had it stuck in my head for days....
And it's HARD to get around THAT statement!!!

Great Quote Volfy!!

Now how hard can I push these.....

Ryobi (cheap, fast coversion, not much performance)
Now asking if it can hover ANYTHING....

So realistically, you CAN'T HOVER A RYOBI easily???

Simple foam wing/tail construction, aerobatic dimensions....not going to last long...but would be cheap airframe....
I was thinking of sheeting foam with 2 mil Coroplast...easy one step sheeting, color, and fuel proofing all in one application...shrug...but....heavy. Guess I'm getting a little off topic here (better to be in the Scratch Building Forum).

Any other ideas?
High Flights
CrazyHerb

Check out the Jag Engines site for their Ultra Stick 120 with a Ryobi 31 on it. Rather interesting when applied to this thread.

Herb, I'm glad you liked that quote. I have to deal with it EVERY SINGLE DAY.

No matter. When s**t happens, most people still blame the engineer.

With a larger DA, 3W or ZDZ.

Kind of like: "To make a small fortune in RC'ing, one starts out with a large fortune"

DKjens

Good One!!
You got a good chuckle out of me there... DKJens!!

A VERY valid point....and interesting picture of that in my head.

LOL...

It all comes down to "You get what you pay for".

Anyone tried like a Ryobi on a 90 sized UltraStick with the firewall moved back like 2 inches???

First photo posted here of a Ryobi hovering wins!
(bragging rights)

CrazyHerb

If I did not have so many other projects going on now I would put my ryobi in my balsa nova because it would even be able to pull out slowly I will loan by ship and motor if someone wants to set it up in the portland oregon area.



Darin

Here is a hovering ryobi for ya. <G> I am wondering how others went about removing that darn clutch. Hope you liked the picture -Dan

Youll need more than 1:1 to hover.... One to One will only hold the plane in one spot meaning you cant pull out.

I was thing about a small 21cc or 23cc in my Goldberg Ultimate???? What do ya think? Sounds like a bit of fun to me! I had a Saito 150 in it.
:devious:

I had a Ryan's Rebel with a Ryobi on it once. It had unlimited vertical and would hover at about 95% throttle. It would hover but not in the manner that you are asking. With a little work I think you could get a Rya'ns Rebel at 10 lbs w/ a Ryobi.

Ryan

Helicool: When I get on my other putor...I will post a nice photo of a C. G. Ultimate with a 1.4 RCS engine. Capt,n

Yeah, right under $200.00 the only way is to get everything FREE,
then have some one build the plane or whatever to put the engine in then convert the carb to run alcohol for the extra power and maybe , just maybe it might have enough power to swing a decent size prop.

under 200.00 thats rich!

Id love to see it! :greedy:

Im sure I wouldnt have any power issues then!
Which out of all of the conversions do you think weighs the least with the least mods needed? And which has the most power?

21cc 23cc or 25cc

Anyone? Anyone? Bueller? Bueller?

How about the electric Radical R/c edge 540, airframe is 10 oz with electronics!!

Just kidding, try this plane, kinda like a 1.20 size Sig Something extra. wieght is normally around 9 lbs with a 30 oz engine, so you should be in the 10 1/2 lb range if you can push it back and not need wieght for balance.

http://akmodels.bizland.com/3dfreedom.htm

I hear it builds easy and flies great.

You also may want to call CH ign and ask about the "roadrunners" he flies with conversions, kinda like a H9 stick but builds cheaper.....maybe you could add more surface deflection for 3d.


good luck

I'm leaning towards Homelite 45 for that one... helicool.
Drop the saw out of the motor, bolt on a prop hub...
and optional 25 dollar muffler and go...

About 22-25lbs thrust from a 22x8 prop..
Think the motor is right around 4 lbs stock mag/flywheel, but makes up for it in the THRUST department.

HighFlights!
CrazyHerb

Isnt that a bit too big for it? Its meant to fly on a 60-90 2c or a 90-120 4c. I had the Saito 1.50 and it was a screamer. Here is a pic of my 46cc poulan Im almost finished with.