I just got my first RC Airplane off the ground. Big Stik with a 46 AX. I'm new to RC but flew control line as a kid. We always used plastic props. My OS manual recommends Wood Props, and goes on to say that plastic props can disintegrate. I have ran 11-6, and 12-6 Wood props on this motor with no problem or vibration. Ran a 10-6 plastic the other day and noticed much more flex from idle as I throttled up and a little vibration until engine running full speed. I did balance the wood props and not the Plastic one though. In a nutshell 3 questions.

1. Wood or Plastic Props?

2. Does balancing the Prop make that much of a difference?

3. How do you know what pitch and length is right for your motor and plane?

Thanks alot guys, I appreciate the help!!

God Bless!

Nick

First of all, new pilots should use plastic.. either Master Airscrew or APC.

Wood props will pretty much shatter as soon as it hits the ground, which is what new pilots do a lot. You have an even chance of having a plastic prop last a bit longer.. buy several spares.

Balancing is always a good idea. Some won't need it, but checking it is what is necessary.

A good quality plastic prop will be just fine. It may flex a bit but it is fine to learn with. Pick the size that suits you and your flying style. Watch the full throttle RPM and don't exceed 12000 rpm. Excessive rpm do no good at all. Noise does not equate to power.

CGr.

I prefer nylon or plastic props unless I'm trying to achieve a vintage look. The 11X6 should be a great prop for your engine. Balancing makes some difference. Often it isn't needed.

How do you know wwhat prop to use ? Well, the prop on your plan is much like the transmission in your car. Do you want to go slow but go up hill ? Do you want to go fast, but loose climb performance and acceleration ? The mission dictates the prop within the recommended range of props the manufacture suggest. A good sport prop for the 46 is either 11X5 or 11X6. I use a 11X5 on my little Cap232. I want it to climb good, I don't care much about speed. Actually, I love the way it flys with a 11X5, you might want to try one.

On a side note, if you're float flying, you can't use a wood prop. Wood will disintegrate when water splashes onto it.
Paul

Out of curiousity, why did you balance the wood props and not the plastic one?

My brother and I usually do not balance our props. We use Master Airscrew and APC, 10 to 14 inch diameter.

If we do get a vibration we'll balance the prop. We've rarely had one bad enough to cause any issues.

On smaller glow engines i run the APC brand unless it's going on a trainer that my students are going to get ground strikes with, then I go to the Master Airscrews, almost bullet proof. I don't use wood until I go past 17 inches or so then I go right to the Xoar props. I keep a box full of props and test the different sizes and pitches that are in the range of what the manufacture recommends until I {the pilot} can find the one that will fly the plane the way I like the plane to fly. Same rule of thumb as control line engines, longer prop with a lower pitch= slower speed with more torque. Shorter prop with higher pitch= less torque but faster plane with longer take off runs and faster landings. Most props need to be ballanced and it shows up as vibration when you get a bad one. APC props other then a size or two need to be ballanced. In th eXoar wood props they state already ballanced and for the most part that's true but I still stick them on my maching and test them. It's up to the pilot to find that perfect prop, most .46 engines like the 11 inchers but some planes fly a lot better with a different pitch. Up to you to do the testing, I enjoy seeing how my planes react to differnet props, I just hate taking the spinners off and putting them back on again!!

Beginners should avoid APC props also. They have very thin tips that will easily break off.

Get a Master Airscrew 11x6 or 11x7 for that engine. They are cheap and durable. Worry abbout performance when you've gotten good.

BTW, 10x6 is too small for that engine - you'll risk burning the engine up with that.

Man I must be gettin old, I worry too much. Thanks guys for the help. Time to stress test the Plane, Props, and the pilot.

God Bless!

Nick

As long as the plastic props are not too far out of balance, paint the light tip with a contrasting color. That way it balances the prop, and makes it easier to see the tip arc.

For the 46ax I liked an apc 11x6. Wasnt too fast and just worked well for me.

one thing i always wondered was if the wood prop breaks when it hits the ground, and the plastic doesnt, wont the wood prop help save the engine? i use wood props all the time. It was expensive when learning, but it was easier for me to replace a $5 prop instead of a $100 engine. or does a ground strike not cause excessive damage?

Nobody has recommneded reading the engine's instructions, why? All of the engine instructions I have for the engines I've bought have a recommened range for propellers. If you go with somewhere in the middle of the range, it will be a safe size to use. Change to other sizes after you've flown and determined how to get more power or speed if that's what you need. Not bad mouthing anyone offering advice here; but, I will guarrentee the manufacturer knows more about their product that anyone else.

I balance every prop I use. APCs and Master Airscrew props are sharp as razer blades when new, I remove the molding flash and sand the edges to give a safe feel to them. I find doing so generally improves the balance. Wood props will in all likelyhood be out of balance and need balancing. I think it is so easy to balance a prop that it simply makes sense to do to everyone. By the way, remove the price tag!

i use wood props because they break easy and will save the engine a little more in a prop strike rather than a plastic prop that will not break as easy
good luck mate
happy flying

simmo

Save the engine? Are you talking about a prop strike twisting the crankshaft off? NEVER happen on our little glow engines. Never. Go nylon unless you like to keep a wooden prop graveyard.

LOL ok fair enough and i find wood props look nice aswell
so a sudden stop wont hurt a saito fa120 4 stroke ?

From a prop strike, no. The only engine I have ever seen that is prop strike sensitive is my Quadra 35cc gasser. The previous owner had a prop strike with it before he gave it to me. Busted the crankshaft. I use only wood on that engine.

ok cool thanks i learnt somthing new today
what about carbon props how do they compare to everything else ?

I see and understand the thinking behind hurting the engine upon ground strike but this is at landing or take off and as of now I have never seen an engine hurt with a strike. I'm still using a .40 OS LA engine for trainers that has been going strong for so many years I don't even remember how old it is?? Hundreds of ground strikes. MASTER AIRSCREW props: I trained three students to fly on one MAS prop. At one point I figured it was getting a little short so I pulled it and put it on my ballancer, it was still dead on?? Guess it was wearing down both sides on ground strikes??
Mode, using props within the manufactures recomended range would imply reading the instructions. How about just making a sticky of this question with one good answer??? It has worked very well on the question of covering.

When i started flying my trainer i was using a APC. Boy did i go through alot of them. You just barely hit the runway and that prop shatters everywhere. After about 5 props i switched to MasterAirscrew. I can hit the runway with these things and they just need alittle rebalancing. They take a lick'in and keep on turning. I'm better now and don't hit near as often but i have maybe 20 times more flights than the APC's and am only on my 2nd prop. Lov'in for training.

skeeter

So far out of about 4 total flights off water, I have found that to not be true. My wood prop has been splashe at full throttle and been fine. Not to say that it can't happen, but its not a definite thing that will happen every time.

I think he means they break when they hit a wake, sort of like a prop strike, not just getting a splash or two. I have seen wood props at float fly's hit the water and it looked like they hit a brick wall.

I have no doubt that if it nosed over into the water or something similar, that it would become toothpicks. I think it you nose over or get hit by a big enough wake, you got bigger problems than a broken prop.