chevy43

I have read a lot of people saying they don't like Master Air Screw props also that APC are more efficient.

I like MAS props because I think the square tips look good, it can take a hit on the ground without much damage and it is alot safer.

APC loose alot of tip it they touch the ground and the tips are super sharp and dangerous.

I haven't used wood props but they are so light it seems like you would have to have an engine with a really good idle since they don't have much flywheel effect. It seems like they wouldn't take a ground hit very well either.

What do you like?

Missileman

Wooden props do not handle ground strikes well.
APC props do loose the tips fairly easy even just chewing through a bit of tall grass.
MAS are less efficient than APC but are efficient enough for most sport flying and can handle ground strikes fairly well.
MAS props can have really sharp edges and can cut you just as easily as APC.

chevy43

It is the sharp tips of the APC's that worry me - in fact I have been cut badly already by an APC tip while I was trying to get in and adjust the compression on one of my diesels.
A MAS tip can bump you without cutting if it is just a light hit.
I always sand the front and rear edge of any prop.

Geistware

My Feedback: (16)

I would recommend you do two things.
Get a MAS and APC and look at the tips at WOT and idle.
The MAS will flex a lot. The APC will not.
This flex will make the propeller less efficient because it changes shape with applied power.

air mail rcu

I like APCs much better the MAS. Just my $0.02 Seems the balance is much better from the get go.

chevy43

Well I will agree that sometimes the MAS need alot to get them balanced.

But boy are APC's UGLY! Who ever would pick dish water grey for a prop color?

PipeMajor

My Feedback: (1)

I agree with the consensus here that the APC is more efficient than the MAS but is more brittle. After some minor prop strikes on my APC 11x5 would result in 1 prop per every 2-3 flights the folks at the field told me to change over to the MAS. I am still flying a trainer so won't really miss the edge in efficiency but the MAS is a little more durable.

The black MAS props are harder to see when spinning so I've been painting my tips yellow. Looks pretty cool.

If you don't care for the grey color of the APC props they can be dyed to virtually any color. I've had to sand or scrape the molding flash off both brands and find both require balancing.

APC had a problem with some earlier runs where the hole in the hub was not centered.

agexpert

My Feedback: (1)

You guys probably already know this, but APC props are the most efficient small props available. They are heavy, ugly, sharp and brittle, but they are the best small props you can get, especially for the money.

APC props are good props too. They are less efficient, but lighter, more forgiving, look sorta scale, not so sharp, and can take a prop strike better than APC.

Once I stopped letting my prop hit the ground, I never bought a MAS prop again, but if you are learning and bouncing a few landings...get the MAS. It will save you time and money.

When you get over 20 inches, all bets are off. I just buy quality wood props. Some of my CF props cost more than a .40 size trainer. (Not worth it to me anymore).

A propeller is, as you know, much more than a fan. It's a wing. It's the airfoil that makes APC better, more than the rigidity.

Sorry for running on and on like some know-it-all, I am stuck in a motel room and I ate all my take-out already.

Missileman

OTOH,
MAS does have a line of props, I have one of their scimitar style props but haven't tried it out yet.
Of course there are other props out there as well, I have heard Graupner (sp?) are good?

Dr1Driver

You don't build to crash, you build to fly. You don't pick a prop to strike the ground, either, you pick it to fly the airplane.

IMO, MA composite props are only good for one use - trainer planes where ground strikes upon landings may be frequent and the pilot doesn't want to keep buying props. MA props flex front to rear a LOT, the blades flatten out at speed, and they are not very efficient. They absorb a lot of your engine's power. I don't recommend doing this without a full face shield and heavy long sleeve shirt, but stand in line with the prop tips one day and rev the engine. You'll see that I mean. If you're having trouble taking off with your trainer, Brand X engine, and a MA composite prop, don't change or fiddle with the engine, change the prop first. You may be pleasantly surprised.

Over the course of about 25 years of R/C flying, I've used 4 types of props: MA composite, MA wood, Rev-up, and APC.

Rev-Up props were excellent for glow engine use, and I wish they were still manufactured. They were light and had wide blades that provided a lot of thrust with almost no flex. They were EXTREMELY efficient.

MA composite props were good for training. They are mostly well in balance as purchased, but the blades flex a LOT. They eat a LOT of power (see above paragraph). As previously mentioned, they can absorb a ground strike that would send another prop to the trash can. Having said that...ANY prop that has touched anything but air should be removed and thoroughly inspected before being flown again.

For my gas engine use, I like MA wood props. They're not the most efficient prop in the 23cc - 62cc size, but they are a good compromise between cost and performance. They balance easily and don't flex much.

For smaller glow use, I REALLY like the APC. They're VERY stiff, and the blade shape is VERY efficient. They're almost always in balance as purchased.

WARNING: Check the balance on EVERY prop before you run it on an engine. If it's OOB, here's my balancing method.

1. First, if the heavy blade swings violently downwards, or smacks the table top hard with a teeter balancer, TAKE IT BACK. DO NOT try to balance a severely OOB prop.
2. Buy a spray can of clear gloss/satin/flat Poly-U paint.
3. Spray a LIGHT coat on the front of the light blade, then rebalance. Go easy. Don't overdo it or the light blade may become the heavy blade. Continue doing this until it's balanced properly.
4. Let it completely dry and go fly.
5. This works well with wood or composite props.

I am not in favor of sanding a wood prop to balance it, and I would NEVER sand the face or back of a composite prop. What I would do with composite props is scrape the edges to eliminate the scalpel effect. Oh, and that's one very good reason you never finger-start an engine.

Dr.1

da Rock

If you pick the prop that you think hits the ground better, than pick a wooden one.

What's a prop cost?

What's an engine cost? The motor mounts? The front of the airplane?

Any prop that is strong enough that it'll survive hitting the ground is going to transfer all the energy of the hit right back into the engine. If the conrod is strong enough, the energy goes back into the motor mount. They're almost always strong enough to send the engergy right back into the balsa and liteply and plywood.

A couple of airplanes in the shop are 30 years old. I can't count how many wooden props that've been busted on them. They've lasted too long for me to remember. They never had a structural failure or had a switch "suddenly" go bad, or had an "unexplained" RX glitch.

I'd pay more for wood than plastic. If that was the way the prices were, but the price for wood is less not more. win win

da Rock

The idea that one brand is "more efficient" than another and that "everybody already knows" that isn't exactly true.

The proof offered is usually that one brand usually turns higher rpm than the other brands. Wish it was that simple. It's not. Matter of fact, higher rpm on the ground means nothing. And higher rpm anywhere usually means that the higher rpm prop simply has less pitch.

If any prop mfg wanted a sure fire scam to sell more props in this market, all they'd have to do is print a higher pitch number on all their props. This astute buying public would see the higher rpm than normal for that "pitch" and proclaim, "by gooly, it's more efficient" and the scam would start raking in the sales.

As for watching the tips flex....... Props unload in the air for one simple reason. They're loaded abnormally on the ground. They're designed to work in the air with the airplane moving. And does anyone know for sure if the flexing is bad? We don't know for sure if flexing on the ground means anything in the air. And we don't know if it'd be bad or good in the air anyway. So does the abnormal loading on the ground cause the flex? And is that good? or bad?

The original Buster had a fixed pitch prop and was a terror as a plyon racer back in the what? the 30s? 40s? How was it so good? The prop flexed under different loads. While the airplane was still accelerating, the flexing prop accelerated the airplane better. When it was at speed, the flexing prop pulled it faster. Personally, I'd want a flexing prop. At least to test. But first thing I'd want is a couple of different pitch ones. Then I'd test 'em all.

Truth is, we're lucky to be working with model airplanes. We can buy more than one prop. And we can fly all of 'em in consecutive flights and find out what really matters, theory or practice. In practice, we can easily find what prop works better. Easily and cheaply.

da Rock

BTW, did you know that heavy props turn faster on the ground than light ones?

What's the heaviest prop nowadays? Those gray plastic ones?

On the ground the prop is loaded. It's loaded because it's airfoil is stalling or closer to stall. It's loaded because it's AngleOfAttack is greater on the ground. Larger AOA means the wing's operating at a higher lift. Higher lift is higher drag. The slower prop on the ground is making more lift/drag than the faster prop. But both are loaded more than they'd be in the air.

Against a higher load, any engine will usually turn slower. But you can help the engine. You can give it a flywheel. If you don't give it a flywheel, you can give an airplane engine a heavier prop. Then the engine can build up momentum and wind up with higher rpm. (.... wind up.... with higher rpm...... is that a joke?).

Jim Thomerson

Once you get to the point you are concerned about best performance from your airplane, try some different props. You will see differences in performance. I usually start out with APC's, but I have been surprised to find that they were not the best for some particular airplane/engine combinations.

TexasAirBoss

My Feedback: (22)

I used MAS props for a long time before I tried an APC. Now, I run almost all APC props. Occasionally, I find the odd situation where a Graupner will out perform the APC.



When An airframe is tuned to my liking, and all the variables seem to be nailed down, I will take a fist full of props to the field and compare them on the plane. I will vary the pitch and diameter and brand slightly. Sometimes, you just never know which prop will perform the best in an application. If the plane is sleek and fast it might perform better with more pitch. If the plane is blunt and fat, and climb performance is more important, then less pitch is generally more effective. That seems simple enough. But finding the prop that works just right? That takes a little trail and error.

People have started taking prop selection a little more seriously. Its seems that the extra performance gained with the optimum propeller selection is worth pursuing. Prop testing can get expensive. Some sport props sell for 7 or 8 bucks. Taking a fist full of props to the field for testing can easily represent an investment of 60 or 70 bucks. And off course the cost of giant props is off the chart. Fortunately many folks right here on RCU have tested and have data to share. Just ask about any combination that you are considering and someone will have experience and opinions to share.

britbrat

Generalities are -- generalities.

You just can't pick a specific manufacturer's props & say with certainty--"they are the best", or "they are the most efficient". It just isn't true, and cannot ever be true because the engine/airframe/prop combo operates in a highly interactive manner. Change one element & the performance of the remaining two elements changes individually in response -- as does the performance of the combined system -- & often in unexpected ways.

Additionally, the particular end-use of the aircraft will be another determinant in selecting the best available compromise -- and the word "compromise" is just about the only absolute in the whole business. Change the intended end-use, and another "best" compromise solution will arrise.

I find that MAS & APC both make props that work "best" on particular airframes and with particular engines, for a particular end-use. There are also other "best" manufactures out there.

Intelligent, open-minded experimentation with different prop types from the same manufacturer, as well as from different manufacturers, will show you what you need to know -- don't trap yourself into limiting your options through rigid personal preferences.

NorfolkSouthern

The APC props may work, but they are UGLY. I would never buy one, no matter how good an efficient it is, unless I was strictly into competition and looks didn't matter. They disappear when at full RPM. They're sharp, stiff, and in my opinion dangerous. Since everybody buys them, they'll likely be the only game left in town, like Microsoft and operating systems.

NorfolkSouthern

RVM

Performance > aesthetics.

Frankly I don't see how an APC is any more dangerous than a MAS. A prop strike to the finger (or anywhere else), regardless of the prop, is going to cause some serious damage. The better solution here, rather than using a generally less efficient prop (MAS), is to be more careful. With the proper precautions, you don't have to worry about the relative damage caused by one prop or the other, all you have to concern yourself with is which prop is best for your particular application.

Dr1Driver

Dull knives cause more accidents than sharp ones because the user gets careless and complacent. Same with props. RVM said it good, ANY prop will hurt ya BADLY!

Dr.1

NCIS

I only build large scale planes from kits and use the Master Airscrew K series for the authentic look. APC is a good prop but looks funky on a scale bird. For 3D I guess APC is the way to go. My vote is for Master Airscrew.

Gibbs