Yasbush

What's the difference other than looks is this type of prop to a regular master airscrew gf series?

JohnBuckner

My Feedback: (1)

I am one that generally will avoid the Master props and tend to use more APC (landing products) than anything else along with some wood props on vintage stuff. This primarily because I believe in many cases, even the majority that the APC performs just a tad better for me.

The APC is much stiffer than the Masters and that flexibility of the Master product does rob power, of couse if you have lots of prop strikes the Masters often will survive where the APC will break. If one wears safety glasses and stands back in line with the propeller tip path plain and have someone open the throttle from idle, The amount of forward bending Is almost shocking and guess what, it takes power to do all this bending.

Its just what works for me

John

Some complain of the APC's sharp edges, well over the years I have seen about the same amont of blood and gore with both brands.

Rafael23cc

My Feedback: (6)

Since this is the Beginners forum, I'll take a gander and suggest you stay away from them for now. Once you get used to the speed of the "normal" props, then "upgrade" to the APC props.

Reading the post above will make you believe that you will have no power with the Master Airscrew props. Although you _will_ have diminished power, there will be plenty of power to learn to fly and basic aerobatics. It is only when you move into advanced aerobatics that you will need the power of the APC prop. (And possibly a different airframe)

I used to have a normal 40-sized trainer with a "normal" prop and the recommended flying surface throw. After it got boring, I "upgraded" to an APC prop and modified the flying surface throw a little. That airplane became a completely different flying machine.

Rafael

Yasbush

Thanks for the quick answer. I've been out of the hobby over 20 years and recently purchased Great planes ultra sport 60 with an APC Prop on an OS 61, having a 40 size ultra previously with a tuned pipe. Never used an APC prop. Thanks.

JohnBuckner

My Feedback: (1)

Thank you Yasbush and I think you will enjoy the combination the Ultra Sports were great airplanes as well as the OS .61, What model FX? and what size is your APC prop?

And to the gentleman above I most certainly did not state that "will make you beleve you will have no power" That sir is absurd and I implied no such thing. What I did state is my opinion of the two and why. Last time I checked I as well as you are allowed an opinion.

John

jester_s1

It's not as simple as some have made it sound. In very simple terms, APC props load the engine more. Put the equivalent size of both on any engine and the APC will have a lower RPM. The wide blades move more air, which if why they take more power. So sometimes the best prop for a given plane is a bigger MAS.

Rafael23cc

My Feedback: (6)

Of course you are allowed your opinion. And I do not doubt that you have plenty of experience. You just have to mold your opinion to your audience. It just so happens that this gentleman does have _some_ experience. But this is the beginners forum after all. it is all about perspective.

Rafael

Yasbush

It has an OS max SF with a 12x6 APC prop. Haven't flown it yet. Waiting on a new receiver ordered for my radio.

jetmech05

I believe that APC is a better prop. MAS props flex a lot more and one blade always seems to flex more than the other.
the down side to APC is they are sharp. Always run an exactly knief along the edges to dull them down a bit.
Personally I'll always take an APC over a MAS

rgburrill

APC is a good way to slice your fingers when you flip start a nitro engine.

JohnBuckner

My Feedback: (1)

The 12x6 should work well with the SF another possibility with that airframe would be an 11x7 APC. It may be fun to experiment sometime.

I keep a well stocked "prop wall" just for that purpose and yes the are mostly APC. Another brand that I did like a lot was the Bolly from down under. They too performed very well in every application I ever used them. What was nice was the selection since they came in half inch pitch sizes, The down side of the Bolly was just they were just more difficult to find.

John

jrf

My Feedback: (551)

I'm sure it is just a typing error, but Jester stated it exactly backward. The Master Airscrew is the one with the wide blades and it is the one that loads the engine more. The same size APC will usually give more rpm and therefore a higher top speed.

Most of the hobby shops in my area have stopped carrying the Master Airscrew 2 blade props.

oliveDrab

Fly electric planes with electric props.

jester_s1

jrf- I said it like I meant to. I probably should have clarified though. MAS has several styles of prop- I've used the Scimitar, the classic, and the K series at different times. The K series props are wide bladed and require more torque to swing. They were designed for 4 stroke and torquey 2 stroke engines to run well at lower RPMs. But the other two are thinner, and in my experience will unwind a bit more in the air. I don't have a tach attached to my plane in flight, but it's simple enough to hear the engine noise and notice the change in pitch between one prop and another. Whether it's actually an advantage is another issue entirely as prop performance depends on a lot of variables.

Yasbush

Thanks everyone. I learned a lot.

jetmech05

Real airplanes aren't electric.

CESSNA 421

My Feedback: (17)

If you can find them the old REV-UP props were superior to most other prop at the time. I managed to buy a dozen of every size before they went out of business and that is all I use on my glow engines. The one issue they had was being out of balance, most of the time they were way off. This was not an issue for me since I balance my props with a light film of urethane clear paint.

ratshooter

Yep. What he said. I miss the Taipan props I used to buy from Lone Star Balsa. Those bat winged dudes moved some air.

HighPlains

My Feedback: (1)

I think the MAS props are far better for mixing paint, but the APC are better for flying. I knew Fred Burgdorf quite well when he was getting Landing Products off the ground, and incidentally worked for Chris Machin of Rev-Up back in the 70's while in college. Both were making the best product in their respective era, and sadly both have passed on. Machin made his first prop in 1949, and last one in 90's after he lost his wife. Burgdorf started in the 80's with a lot of help from his brother Otto. Something like 30,000 lines of code to mill the molds. The difficult part was the transition between the blades and the hubs.

J330

My Feedback: (3)

I have always liked APC over MAS after a flight comparison. I never said "Oh I got to get this APC off and get a MAS on this."
But, the talk about sharp edges starting being a safety problem, don't forget the event of ever hitting this prop with anything when it's spinning 2,500-11,500 rpm (OS 61 typical range with a 12X6), how that reinforced prop will do severe and permanent damage as well was the MAS. I keep a 1st aid kit in the truck at every flying meet just in case. Wood has no sharp edges, wood wins when starting safe, not sure if it would do less damage to flesh spun up high, but they do break. That's safety there too.
The pitch goes flatter the easiest on APC, so you might want to try a 11X7 on that Ultra 60.


Wood is lighter. They spool up faster than heavy props, they don't auger in the ground bending crankshafts, wood snaps at the prop nut, not APC. You might get lucky and just break the firewall with APC. Wood wins taking the hit in a crash.

Pitch on wood props maintains it's integrity better than polymers, less deflection. If you're a beginner, you'll be making contact with the ground more and wood is not forgiving. Props are relatively cheap, go buy the three or four choices and test for yourselves. That's what makes it a hobby. To each his own.

acdii

i've used both APC and MAS K series, and the APC wins hands down for getting the most out of an engine. I have a MAS Scimitar on my P-51 and it pulls nicely. I stopped using MAS after witnessing too much flex and wobble on my engines, and APC is recommended to use on Saito's which is what I use.

Any prop can cause great harm. Always be careful around them and make damn sure your plane is properly secured when running a motor. One of the guys at my field was running up his plane, which had a DLE 30 and wooden XOAR prop onit. The wings were at the very top of the hold back on the run up bench, and when he throttled up the left wing lifted up and the plane spun around and chopped his arm up big time. Luckily there were other guys at the field who saw it and was able to get the bleeding stopped and get 911. They had to fly him out on a Flight for Life. He lost some use of his right hand and has grooves in his arm from where the prop chopped through.

Does not matter what prop it is, or what it is made of, any prop can slice you up. APC do have a sharp edge, but when balancing, sanding the leading and trailing edges helps reduce the sharpness, but it is never a good idea to finger flip a prop without some sort of protection be it a glove or a chicken stick. I found mechanics gloves with the knuckle pads work great for this.

jester_s1

A razor sharp trailing edge is a good thing. It lets that high speed air meet back up with a minimum of turbulence and cavitation. Blunting the trailing edge of a prop can have a substantial effect on its performance.

HighPlains

My Feedback: (1)

Air does not have cavitation, only happens in liquids.

jester_s1

I may have used the wrong word, but when you drag a rounded shape through air at high speed you get a vacuum bubble behind it that significantly increases drag.

J330

My Feedback: (3)

Anything spinning is going to cut, but flipping a prop over to start it, it's best to use an electric starter. Wood is not sharp on the edge as APC, was my point.
Every prop works like a wing, the backside is flat, the front of the prop has it's own airfoil shape, so altering that airfoil just doesn't make any sense if you've been after performance from the start in selecting APC. I never alter my props for dulling anything.

Another point, most of my wood props have spot on balance. If you shoot for balance ( and know it's not the hub ), sand from the backside only.