I'm new to gassers and just got my new Brillelli 36GT, but not installed yet. My question is I've always flown glow engines, when I started I generally used Top Flight props or Master Airscrew, then along came APC and I've used them every sense. Now I get into gassers and I've been reading all the posts and I can't find anyone that uses APC on a gasser. Most are using Xoar or another similar wooden prop. My local hobby shop stocks the large APC's why are they not used? Is it a 3D thing because I'm going to be sport flying?

Brands are as individual as the airplanes we fly and the style we are accustomed to. Your gasser will turn lower RPM's than your glows, so your props will deflect less, however your gasser will probably turn a larger prop. Te beautiful thing about the Xoar's (Yeah I use em and love em) is that they are beautifully balanced and they are just a fantastic prop. Fly what you want, it won't make a huge difference, until you try a high end prop. Then you won't go back!

Truth be told, most of the TF, Zinger, MA, and APC props just aren't all that good for large plane flying. Yea, they will get the plane in the air but usually will come up lacking. With the APC's, you really don't want to be drilling the things for a mulit bolt hub. If you do don't be standing close when they are turning on an engine.

The best performance with any airframe/engine combination will come with experimentation. When you ask someone for the "best prop" for an engine you are receiving subjective information based upon the one person's results. It either suited him or did not. You truly don't have a clue how it performed in any area other than rpm unless a thrust determination was also made. Spread sheet thrust calculators can come close, but are not very accurate in measuring real "in flight" performance in all the areas that a propeller effects, which is many.

Essentially be prepared to spend some money in trying props in different sizes from different manufacturers. It will be expensive, but worth it. If you are unwilling to step up to the plate and do this the only performance you will ever experience will be that belonging to someone else, with a high likelyhood of never having the best performance that you could. Look to the better prop manufacturers such as Menz, Bolly, Mejzlik, Fuchs, Biela, 3W, **Xoar/NX/BME/WildHare (all the same prop)**, TBM, MSC, and PT. Forget you ever knew Zinger, MA, and TF ever existed. Now that you've stepped up, they no longer do for you. Remember that rpm does not always (or often) correlate with thrust. Frequently lower rpm provides better performance for many things. Other times higher rpm provides what is desired.

Those that make the step to gassers usually do so because they are going to fly larger planes and require increased performance levels across the board. That performance will not come on the cheap, and those unwilling or unable to spend the money will never see the performance they desire. You hear them crying all the time looking for a cheaper engine or other product.

SS, that was really a mouthful, but all truths and stated exactly as I now see it. When I stepped up from glow to gas, and it was a big step for me, I too was unaware that there were so many props other than MA, APC,TF and Zingers.

But more importantly, these new found props were of such quality and provided a level of performance that was just never obtainable with the brand props that I was accustomed to using.

For me back then an APC was the Holy Grail, and now I realise that if you just want to putter around that's fine, but if you like most others want more then there is an additional cost attached to achieving really good performance, and more than likely once you have tasted it there is just no turning back.

Now I just can't think of putting anything but a Xoar prop or it's equivalent on my engine. Just my 02 cents.

Karol

Ed Skorepa has some new props made from extremely hard wood (hard as a Czech's head) -I have not tried em but I do find that "flexible flyer" props are a no -no on high loads . even on my itty bitty electrics
ZDZ also has some new blades which are beech (Ithink ) but ar shaped for high load stability - the 20x12 we ran on a ZDZ40F3A piped -was very quiet and pulled like a freight train.

One of the guys at the local hobby store said the guys in Wichita will stay far away if you try and run an APC on a gasser because they're affraid they'll come apart on a gas engine. I was skeptical because why would they be made in the large sizes if they were dangerous. I think from what little I've read, they just can't be drilled for multiple bolt hubs....True?

I was told early in my gas life that using anthing larger than an 18" dia APC on a gasser was a definite no no. Having heard several stories of APC props coming apart for whatever the reason, it made a believer out of me.

Karol

Big problem-- people using the APC props incorrectly.
These props can be bent hard without showing physical signs of stress -
Stressed plastics are invitations to failure .
I have never had a seconds problem with the APC props -up to inc 20"dia.
But some guys can screw up a wet dream--
I gave some small electric props to a guy for his tiny 370 Eflight motor .
he called me to tell me the last of the props had broken on "hard landing" but that super glue I gave him also worked to glue the hub and blades back together and it worked !
True story --
in late 1980s the slick new prop was a light green plastic prop -for pattern flying -- I loaned one of my friends, a plane to practice for the TOC and he came back to the house with the plane in one hand and the motor and nose section in the other -
the prop had simply exploded in the air and he landed it sans entire nose section (tricky).

How plastic props are formulated and cast means a lot - these particular ones showed stress lines fairly easily but the hub section was hidden by the spinner ---

The moral of that story appears to be "if you know what you are doing and fully understand the products and risks you can do fine, but be careful anyway" Is that close? I know what you mean about people trying to re-use a prop after a ground strike. Just because there is no externally visible damage they figure it's still good to go...

Where are you obtaining those ZM (ZN?) carbon props you posted in another thread? Whe I get back I'd like to look into a couple of those. Thanks.

RCShowcase has the ZM line -and the ZDZ props
I really like the higher pitched props - performance wise - they do the job and are more quiet.
Going by the numbers on a prop -it is hard to seperate the wheat from the chaf.

pumbadog You can use the APC props, heck go to a unlimited race thats about all they use. probably safe to say that unlimited racers are turning more revs than you will. What keeps people from APC is the weight, they are very heavy, and at low rpms it puts a lot of shock load on the airframe to swing them. People use the thick wood props to cut down on prop noise. What I do is get an oversize TF prop and trim it to a size that my engine likes to run. TF makes very good props from a very good wood, however they are very thin too and will flex if you rev them too much. You might possibly get more performance from a thin prop than a thick prop concidering that you are talking about a 36cc engine, thats a little diferent from a 3W106 or DA100 etc. If you want to try a thick wood prop try the NX props they slow your engine down but give you back a lot in thrust with very little noise.

Thanks for all the info. I was just concerned that an APC could be dangerous on a gasser. I can easily go to the local hobby shop and by a 20 X 8 APC or Zinger if I have to, but the better props are harder to get. I did buy a Xoar but they only had the one in stock. I wont be doing any major aerobatics, just basic stuff and having fun punching holes in the air. Thanks again for all the information.

I am buying a G 26 for a 120 ultra Stik and APC 16 x 8 is the only recemend prop by Genoah.

RvMan56

Traveling and Flying
Farmington, NM for now.

if you want a pulling prop try a 3W, and the 5 I have bought were close to balanced right out of the bag..

Jim

Thanks, is the 3w apc, haven't heard of it. Being not the best pilot in the world I think the power prop is better than speed, I ultra stick handles good slow, big flaps, I have been out of rc ing a while. Thanks for the input.

RvMan56

3W is a wood prop,,


edited

Brillelli 36GT ,
my MVVS 35 gasser pulls a 3W 20x8 at 7000, so if your Brillelli 36GT is as powerful as my MVVS then I would say try (if it's not to close to the ground) a 20x6, 20x8, 21x6, 18x10, 19x10

see 3W props here, once in click on products ,,
http://aircraftinternational.com/

Jim

A 16x8 prop is a bit small for the G26. A 17x8 or 18x6 has been proven to be a much better choice.

Karol

As a matter of fact, the Zenoah manual as viewed on the Horizon Hobbies web site recommends 16x8-10 and 18x6 props for the G26. For what it's worth I use a 16x8 on my G20.

Karol

Thanks, I haven't seen the 18 mentioned anywhere but on your advise I have included 18 x 4 and 18 x 6 in my wish list for my future order, my satellite has been done else a sooner reply, thanks.

RvMan56

Balance, balance, balance. Whatever prop you choose, baslance it with a good quality balancer. I use one with magnetic suspension. Virtually no friction. Your engine will run better, your airframe and electronics including even switches will be protected better, and your prop will be safer.

Just a quick comment here:

I've become a HUGE fan of Xoar props...running them or have run them (in various sizes) on a US Engines 41cc, a pair of G-62's, and a BCMA 40. In every case, they've wound up being my favorite prop on those engines.

Yes I have on order the magnet balancer and about 1000.00 worth of stuff, 7ch spectrum's, g26, 120 ultra stik, between horizon and tower my rv my never move again. I read where folks use Coleman fuel, bought can at wal mart the other day, can always fill it with gas, ordered fill-in station and the works. Does the G26 need any special mounting to the 120 ultra stik.?

Thanks RvMan56

Dear Friends,

On Aug 31st, 2007, long waited Xoar new prop series - "The Sword" will be availabe for the market.

It featured metallic pigment coating, corrosion resistant. Comes in 3 colors, Black, Silver and White.

Pre-ballance of Beauty and Performance comes as standard.

Thank you for your support.

Xoar