Avaiojet

I started a Thread to determine which engine I should use for a particular project. My interest, at that time, was 4 stroke VS. 2 stroke.

I'm re-thinking it. I'm considering "GAS" because I was told I should.

What would be the smallest gas engine that can swing a 14" three blade prop? Yes, if I have to I'll swing a standard two blade at 14".

It's for an 80" twin project, see photo below. Please note the large nacelles.

That's my question and all advice will be appreciated.

FYI. I know absolutely nothing about Gas Engines.

Thanks,

Charles

RCKen

My Feedback: (9)

The smallest I know of is the Saito FG-20. It's a 60 sized gas 4-stroke engine. Zenoah also makes a 60 sized gas, but the layout of the engine make is a bit hard to fit in some cowls. The good thing about the Saito FG-20 is that it's looks like a standard glow 4-stroke engine, so it will fit in a lot of engine compartments and cowls. The bad thing about the Saito is the price, $529!!!! But here are the two that I know of

[link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=SAIEG20]Saito FG-20[link]

[link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=ZENE20EI]Zenoah 20cc[/link]

Hope this helps

Ken

3rd Time

Don't waste your time on A FG-20 it is a piece of junk read the posts under gas engines. Mine has been back for repairs twice now and it still isn't usable.

Avaiojet

Thanks for the replies.

OK, that's good news and bad news.

Still gotta through a 14" prop, 3 blade hopefully.

Suggestions?

Charles

RCKen

My Feedback: (9)

Depending on the size of the cowl you are going to use you might be able to fit the Zenoah 20cc in.

Ken

Edwin

My Feedback: (2)

There is also the BME .90. A ST.90 converted to gas. Dont know much else about it.
Edwin

aussiesteve

There is also the RCGF 20cc Rear Carb (also available in a side carb).

And the SV 17cc (I think TBM has them now)

42etus

My Feedback: (2)

Who said you should and what was their reasoning? Not that I'm against gassers, I'm not, but if you're set on a 14" prop, there's a boat load of glow engines that'll swing that size, but with gas you're quite limited.
Paul

Zippi

My Feedback: (10)

Avaiojet,

This may not be the smallest but it is a small 17cc gasser that swings a 14' - 15" prop.

http://www.rcshowcase.com/html/RCS/rcssv17.html

RC Extreme power

My Feedback: (24)

When you say smallest are you talking about CC, Weight or actual size, Just because they are smaller CC does not mean that they are the lightest.

These are weights taken from web sites

Zenoah With electronic ignition
20cc 41.6 ozs
26cc 53.6 ozs

SV 17 41.6 ozs

RCGF 20cc 38.1 ozs
RCGF 26cc 39.5 ozs

So going smaller cc does not mean it is the best engine for size and cc

Now a good 26 cc in the weight range of 32-34 ozs all up would be good. That would be keeping in the same range as a 140-4 stroke.

Milton

Hossfly

IMO, it's probably because someone knows that gas is many times more reliable than glow engines. Gas burners just don't deide to stop for unknown reasons like glow engines do from time to time.

In a multi-engine model this is very important. Very few RC pilots have the experience to quickly switch to rudder vice ailerons when an engine quits on one side, thus losing the airplane. After all, one uses ailerons for roll control most of the time. It is only natural to do same when a model engine quits.
In addition, not being in the cockpit when the engine-out yaw happens, it takes more time to decide which way rudder should be applied. By then it can be too late to recover, especially if trying to do so with aileron control only.
Thus the advice of experienced multi-pilots will generally be to use the most reliable engines.
As it is written somewhere, an ounce of prevention is worth a pound of cure.

Edited to add: Thanks Zippi for that link. Those look really good and the price is right.

jimmyjames213

My Feedback: (2)

found that engine for 145
http://www.troybuiltmodels.com/ns/ac...s/engines/rcs/

Avaiojet

Thank you gentleman, I am learning.

That 17cc engine weighs in at 2.6 lbs. So, that's 5.2 lbs. total for both engines. 80" in span?

As I said, I know nothing of GAS engines, but that seems to be quight a bit of weight?

Charles

mustangman177

Get 2 Ryobi 31 weedeater engines, convert for flight, they'll do fine.


http://www.rcuniverse.com/gallery/ga...6memid%3D16901


http://www.rcuniverse.com/gallery/ga...6memid%3D16901

Avaiojet

Unusual design. looks like all metal?

C

mustangman177

Noooooooooo, 2 and 4mm. Coroplast for the wings, tail feathers, and control surfaces, 4" fence post cover for the fusealage

Go to spadtothebone.com and look around there for a cheaper-alternate way to make airplanes. They're awesome

Avaiojet

WOW!

Better than cool. Incredably cool!

I'll take a Link and send you a bunch of SPAD graphics!

cfcgraphics.com

mustangman177

Thanks !!! I appreciate that.

Take a look at the "free plans section". Doesn't take much money to build a good flying airplane. I've been doing this for about 7 years now, and has totally changed my way of thinking about building and flying airplanes.

Have fun and keep me informed if you want to go the SPAD route. I'll help you in any way I can. Visit the forums at spadworld.com TOTALLY amazing !!!

Cary

Avaiojet

No "scale!"

C

draftman1

well some of us are working on that! look at my gallery on spadworld and my site

mustangman177

True.............Spads are not truly "Scale" airplanes. The whole concept of Spad airplanes is to build a airplane that is airworthy, fairly cheap that can take alot of abuse than that of its balsa counterparts. They are particulary helpful to the beginning pilot who would crash their balsa trainer and be totalled, but the SPAD being more resilient would still be able to fly with minimal damage.

Looking at the "Crashes" forum, you'll see from time to time beautiful-expensive airplanes that have crashed, often involving $1,000.'s of dollars and many man hours building and constructing. I too have done this. Crashed a beautiful detailed Pica 1/5 scale P-51 Mustang (hence my log in name), and a Great Planes Lear Jet, to name a few, both due to pilot error. Flying SPADs takes the "Pucker Factor" out of flying and allow you to enjoy your flying experiences.

When the first SPAD was built, I'm sure it looked like the old Dura Trainer put put by GP in the late 80's? A freind of mine trained on this and it worked beautifully then. With the costs of balsa models being high, and SPADs cheap.....it is a good route to go. As SPADS evolved, some modelrs (like Draftsman 1), have taken SPADs to a higher level building like scale or scale models. Do a little digging through the posts, they're are some ingenious-creative modelers out there !!!! and that's part of the fun of it, designing-creating-building and flying a model YOU have created-not someone in a office-factory mass producing models.

I know this all sounds a bit preachy, that I'm putting down the balsa models,.......Not so. I've probably owned-built 25 models since the late 80's, still have 7-8 hanging on the walls of my "Hobby Shop". But when my buddy's call me and they want to fly-I grab the my Mig-7, my Extra 300, or my USS.

Mustangman