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Author Topic: 3 blade MA 10/5 propeller  (Read 3907 times)

Offline Allen Eshleman

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3 blade MA 10/5 propeller
« on: March 25, 2021, 12:54:01 PM »
Has anyone tried the 3 blade Master Airscrew propeller on an LA46? It is actually a 10/5 Would it work well in place of an APC 11/4 or 11.5x 41/2?  It's just a thought.  I am thinking mostly of trying it on a rather heavy Vector 40 ARF that is heavy because of repairs.  Also I have a Vector 40 profile to build on which I plan to use a B-40.  It gives another half inch of clearance on grass.

Thanks in Advance

 
« Last Edit: March 28, 2021, 10:37:47 AM by Allen Eshleman »

Offline Craig Beswick

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Re: 3 blade MA 10/6 propeller
« Reply #1 on: March 25, 2021, 01:40:11 PM »
APC 12.25 x 3.75 on an LA46 in a heavy Vector 40.

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Offline Dan McEntee

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Re: 3 blade MA 10/6 propeller
« Reply #2 on: March 25, 2021, 04:41:26 PM »
  Master Airscrew three blades are nice, reasonably priced prop. I have experimented with them quite a bit. The pitch on MA props is measured differently by the factory, so they tend to measure 1" under what they say on them when measured on a Prather pitch gauge.  Go to their website and see what they have available in three blades for glow engine use. I don't have a current list in front of me, but their older packaging didn't list much in the 11" range other than a 11-7 and 11-8. They are easy to repitch, and hold the setting once you are satisfied with it. I have used their 10-5 quite a bit and it may be what you want to start with. This prop was added to their listing years ago due t the efforts of some one here on Stunthanger, who contacted the company asking for something with less pitch. His name escapes me right now, but he announced it here on the open forum and took orders.  Windsor Propeller has kept it in their line up ever since and it is available in a left hand prop now also. I think their sizing jumps up to 10-7 after that but it should measure 10-6 on a pitch gauge and can be repitched to a 10-5 if necessary. Their more recent props of all kinds seem to work better that they did years ago and have a better airfoil. Just sand off the flashing left over from molding  and check balance. I would take a 10-5 right out of the package, clean up the flashing, check balance and try it on your Vector and go from there.
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Offline Allen Eshleman

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Re: 3 blade MA 10/6 propeller
« Reply #3 on: March 25, 2021, 05:51:55 PM »
I have one of the 10/6 propellers but haven't used it yet.  As long as it won't cause any harm to the engine, I think I will give it a try.

Offline Brett Buck

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Re: 3 blade MA 10/6 propeller
« Reply #4 on: March 25, 2021, 05:58:53 PM »
I have one of the 10/6 propellers but haven't used it yet.  As long as it won't cause any harm to the engine, I think I will give it a try.

  It won't hurt the engine, so this is a safe experiment. It will have wildly different performance, that is increasing the pitch by 50%. But you never know for sure until you try it.

    Brett

Offline Dan McEntee

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Re: 3 blade MA 10/6 propeller
« Reply #5 on: March 25, 2021, 07:09:54 PM »
I have one of the 10/6 propellers but haven't used it yet.  As long as it won't cause any harm to the engine, I think I will give it a try.

    Yeah, should be OK, but remember it's a 5 inch pitch on a pitch gauge. Take off RPM will be much lower, probably in the high 8000 range, just don't over do it. If it is promising, get some of the 10-5s and spin them up a bit more.  If you can borrow a pitch gauge and repitch one to something in between you may have things covered pretty well.
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Offline Allen Eshleman

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Re: 3 blade MA 10/6 propeller
« Reply #6 on: March 25, 2021, 08:29:01 PM »
Is 5 or 6 pitch too high for these engines?  I know they like to spin fast.

Offline Dan McEntee

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Re: 3 blade MA 10/6 propeller
« Reply #7 on: March 25, 2021, 10:47:34 PM »
Is 5 or 6 pitch too high for these engines?  I know they like to spin fast.

   Again, remember that the MA 10-6 really isn't a 6" pitch and the 10-5 really isn't a 5". You are also down to 10" in diameter and that changes some things also. Just take it easy on the first few flights and experiment with different take off RPM and listen to the feedback from the engine after it gets into the air and unloads a bit. Make subtle changes in RPM as you progress. If the engine starts to sag and gets hot, you are at the limit f too much pitch and time to go down. But you really have to abuse it before you will hurt anything. that is where the castor in the fuel comes in. Like I mentioned, if the 6 is all you have, just take it easy but get some of the 10-5s. I'm betting that the 10-5 spinning in the 9000 RPM range is what you will be looking at. If you think it can stand a little more pitch, do it at 1/4" at a time. You can do that with any good pitch gauge and some practice.

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Offline Brett Buck

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Re: 3 blade MA 10/6 propeller
« Reply #8 on: March 25, 2021, 11:17:41 PM »
Is 5 or 6 pitch too high for these engines?  I know they like to spin fast.

   Maybe, but only one way to find out. The problem will be if it has to turn a lot slower, the fuel draw will go down. the '6"' will be making that more likely, but the diameter will help you by reducing the efficiency enough to let you kill some power.

    Brett

Offline Allen Eshleman

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Re: 3 blade MA 10/6 propeller
« Reply #9 on: March 27, 2021, 11:29:04 AM »
I am also curious if anyone has ever tried the MA three blade 10/6 with an LA 46.   I think I will for the fun of it.


Offline Dan McEntee

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Re: 3 blade MA 10/6 propeller
« Reply #10 on: March 27, 2021, 02:22:17 PM »
  Master Airscrew does not make a 10-6. They make a 10-5 and a 10-7. Like I have mentioned before, they are 1" under what they say on the label, so the 10-7 is REALLY a 10-6. Master Airscrew determines the pitch by some other method and this is the way it is. The good news is that they are pretty constant. Try the 10-7 carefully. If it's too much pitch, just repitch it down to a 6. Get some 10-5s also, because I still think that is where you will end up. Go to their website and check out their line of 3 blade pops and get familiar with them.
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Offline Dennis Toth

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Re: 3 blade MA 10/6 propeller
« Reply #11 on: March 28, 2021, 10:32:37 AM »
Allen,
I have use the MA 3 blade on and electric setup and what Dan said about the pitch being 1" low I can attest to. One thing you should do with these props is clean the flash off the leading and trailing edge with 400 wet sand paper then carefully balance the prop. I have done this by sanding the face of the heavy blade with the set 400 then once near finial switched to wet 600. A second way is to paint a 1" strip at the tip of the light blades with clear acrylic lacquer, go in thin coats and you kinda have to give it a day or so to gas off between coats. This takes longer then sanding but either one works. 

Best,   DennisT

Offline Allen Eshleman

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Re: 3 blade MA 10/5 propeller
« Reply #12 on: March 28, 2021, 10:39:38 AM »
I am very embarrassed.  This is a 10/5 prop!  Not a 10/6.  I don't know if that makes any difference.

Offline Allen Eshleman

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Re: 3 blade MA 10/6 propeller
« Reply #13 on: March 28, 2021, 10:43:18 AM »

  Master Airscrew does not make a 10-6. They make a 10-5 and a 10-7. Like I have mentioned before, they are 1" under what they say on the label, so the 10-7 is REALLY a 10-6. Master Airscrew determines the pitch by some other method and this is the way it is. The good news is that they are pretty constant. Try the 10-7 carefully. If it's too much pitch, just repitch it down to a 6. Get some 10-5s also, because I still think that is where you will end up. Go to their website and check out their line of 3 blade pops and get familiar with them.
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  Dan McEntee

This post made me go back and look at the propeller.  It is indeed a 10/5.  You're right.  They don't make a 10/6 3 bladed prop. I am assuming that this means that it currently truly measures out at 4 pitch.   Does this make any difference for my proposed use?

Offline Dan McEntee

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Re: 3 blade MA 10/6 propeller
« Reply #14 on: March 28, 2021, 11:31:20 AM »
  Master Airscrew does not make a 10-6. They make a 10-5 and a 10-7. Like I have mentioned before, they are 1" under what they say on the label, so the 10-7 is REALLY a 10-6. Master Airscrew determines the pitch by some other method and this is the way it is. The good news is that they are pretty constant. Try the 10-7 carefully. If it's too much pitch, just repitch it down to a 6. Get some 10-5s also, because I still think that is where you will end up. Go to their website and check out their line of 3 blade pops and get familiar with them.
  Type at you later,
  Dan McEntee

This post made me go back and look at the propeller.  It is indeed a 10/5.  You're right.  They don't make a 10/6 3 bladed prop. I am assuming that this means that it currently truly measures out at 4 pitch.   Does this make any difference for my proposed use?

     Nope, like I have been writing, try it just like it is, and this is the one I think you should try first. it might spin up to the 9500 to 9700 range as a starting point and see how it goes. If you think you need a little more pitch, repitch it to a 5 or so. If you have a 10-7 you might want to try that also just for the feed back on how it works. It will rev less, probably in the 8600 to 9000 range. You won't know until you fly one of them.
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Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #15 on: March 28, 2021, 10:01:53 PM »
 I tried the MAS 10x5  3 blade on my LA 46 powered Vector.  The prop did not pull pull the Vector well and had poor line tension. I then tried the 3 blade 11x6, this prop had great line tension but was to much load for the engine. I found when I cut it down to a 10 inch it became a great prop to use, except on real windy days ( to much wind up).
  Al

Offline Brett Buck

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Re: 3 blade MA 10/5 propeller
« Reply #16 on: March 28, 2021, 10:17:38 PM »
I tried the MAS 10x5  3 blade on my LA 46 powered Vector.  The prop did not pull pull the Vector well and had poor line tension. I then tried the 3 blade 11x6, this prop had great line tension but was to much load for the engine. I found when I cut it down to a 10 inch it became a great prop to use, except on real windy days ( to much wind up).
  Al

    Did you match the lap times?

     Brett

Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #17 on: March 29, 2021, 11:19:37 AM »
    Did you match the lap times?

     Brett
  I like to fly at 5.0 to 5.1 on 60’ eyelet to eyelet. By cutting down the 11x6 3 blade I would get a similar engine load and needle setting as a APC 12 1/4 x 3 3/4, 2 bladed prop. The blades on the MAS 11” 3 blade are wider than the blades on the 10”. I even cut it down to 9 3/4 and use it on my Brodak 40 powered Gieseke Nobler.
Al
« Last Edit: January 28, 2024, 05:57:21 AM by Al Ferraro »

Offline Brett Buck

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Re: 3 blade MA 10/5 propeller
« Reply #18 on: March 29, 2021, 01:18:08 PM »
  I like to fly at 5.0 to 5.1 on 60’ eyelet to eyelet. By cutting down the 11x6 3 blade I would get a similar engine load and needle setting as a APC 12 1/4 x 4 3/4, 2 bladed prop. The blades on the MAS 11” 3 blade are wider than the blades on the 10”. I even cut it down to 9 3/4 and use it on my Brodak 40 powered Gieseke Nobler.
Al

  My point was that if you do not match the lap times, you don't know if the difference was just because of lap times, rather than the qualities of the prop. Of course you would have to spin it a lot faster with the lower pitch, but that's part of the advantage of low-pitch props.

    Brett

Online Brent Williams

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Re: 3 blade MA 10/5 propeller
« Reply #19 on: March 29, 2021, 02:25:12 PM »
I  imagine the Master Airscrew 10x5 is closer to 4" pitch or less if it is anything like the MA 10x7.
When I measured the 10x7 on a Prather gauge, it measured mostly in the mid 5" pitch range.

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Offline Dan McEntee

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Re: 3 blade MA 10/5 propeller
« Reply #20 on: March 29, 2021, 04:39:29 PM »
I  imagine the Master Airscrew 10x5 is closer to 4" pitch or less if it is anything like the MA 10x7.
When I measured the 10x7 on a Prather gauge, it measured mostly in the mid 5" pitch range.



    That is what I have been mentioning in every post I made on this thread. MA props are measured at the factory by some other method or theory. They have always been this way. If you cut down a 11-6 to 10" you were closer t o a 10-6 or a bit less. That's why I mention having both sizes available to test. A stock 10-7 is a 10-6 on a pitch gauge. Easy to repitch also and they hold the setting in the sunshine. I don't think their weight is an issue at all, especially if you are trying to trim out a heavy model, which would probably be tail heavy. For the average joe bellcrank, I think they are great props for the money. Something you can work with to learn how to repitch and not be out much if you mess up or crash.
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Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #21 on: March 29, 2021, 05:50:24 PM »
An 11-5 three blade is what you're shooting for with an LA46. The thing about MAS is it's heavy.


Motorman 8)
MAS does not make a 11x5 3 blade. The MAS 11x6 weighs 1oz and is 1/2oz lighter than the APC 12.25 x 3.75.
« Last Edit: June 28, 2021, 08:15:33 PM by Al Ferraro »

Offline Brett Buck

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Re: 3 blade MA 10/5 propeller
« Reply #22 on: March 29, 2021, 05:56:54 PM »
    That is what I have been mentioning in every post I made on this thread. MA props are measured at the factory by some other method or theory. They have always been this way. If you cut down a 11-6 to 10" you were closer t o a 10-6 or a bit less. That's why I mention having both sizes available to test. A stock 10-7 is a 10-6 on a pitch gauge. Easy to repitch also and they hold the setting in the sunshine. I don't think their weight is an issue at all, especially if you are trying to trim out a heavy model, which would probably be tail heavy. For the average joe bellcrank, I think they are great props for the money. Something you can work with to learn how to repitch and not be out much if you mess up or crash.

      What you are seeing (or might be seeing) is what Stuart "Joe Supercool' Sherlock calls "experimental pitch" or  I would refer to as "effective pitch" and "back of blade" angle measurements. What a pitch gauge measures is the angle of the blade, according to the equations in this thread:

https://stunthanger.com/smf/engineering-board/effect-of-wind-on-maneuvers/msg569458/#msg569458

   What you really want if you want to figure out what is going on is the "effective pitch", that is the pitch at which the thrust goes to zero at a forward speed of pitch*rpm. Since the prop blade airfoil has substantial camber, there is always much more effective pitch than the "back of the blade" angle would suggest. I did it for an Eather heavy undercambered prop measuring 3.75" of "back of the blade" angle pitch  and found that the "effective pitch" using Joe Supercool's approximation ranged from 6 to nearly 9" near the tips.

   Note that the same effect also causes the airplane speed to generally go *much faster" than you would expect based on the known RPM and "measured" pitch. I happen to know that my airplane using this 3.75" pitch prop was spinning 10,500 rpm. That's 55 feet/second. It was actually flying at 80 feet/second. If I put on a Bolly prop that measures the same pitch, I might have to spin it 11,500 to get the same 80 feet/second. The difference - far less camber.

  Your MA 10-5 is probably acting much closer to 6+ inches of pitch in practice. I think you will find almost every major manufacturer (Rev-Up, etc) will be very similar - they measure "under"  using our pitch gauges, but have a designed-in correction for camber.

    Brett

Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #23 on: March 29, 2021, 06:15:36 PM »
  My point was that if you do not match the lap times, you don't know if the difference was just because of lap times, rather than the qualities of the prop. Of course you would have to spin it a lot faster with the lower pitch, but that's part of the advantage of low-pitch props.

    Brett
    My LA 46 wasn’t happy with MAS 10x5 3 blade. Over revving the engine to get 4.9 lap times, my Vector felt like it was falling out of the sky at the tops of the maneuvers.
Al

Offline Brett Buck

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Re: 3 blade MA 10/5 propeller
« Reply #24 on: March 29, 2021, 07:57:49 PM »
    My LA 46 wasn’t happy with MAS 10x5 3 blade. Over revving the engine to get 4.9 lap times, my Vector felt like it was falling out of the sky at the tops of the maneuvers.
Al

     I am not trying to catch you on anything here, I am trying to learn - is this engine stock straight from the factory (including the venturi/spraybar/muffler)? I ask because that sort of performance will definitely happen if it is too lean in level flight. That can easily happen with a smaller-than-stock choke area or a tongue muffler. Or. as may be the case here, the prop is too "draggy". It's not that the pitch is too low - since they routinely run very well with 3.75" of pitch and pretty good blade area - but that there is so much drag on the prop otherwise that it has to be run too lean. 

     Brett

Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #25 on: March 29, 2021, 09:16:43 PM »
They don't but I do.


Motorman 8)
That’s a lot more work than clipping a 1/2 inch off of each blade on a 11x6, which is easy to do with the square shape of the blades. I even tried one of those fancy carbon 11x4.5,  3 blades and my prop performed better and it only cost $10.
Al

Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #26 on: March 30, 2021, 09:52:07 AM »
     I am not trying to catch you on anything here, I am trying to learn - is this engine stock straight from the factory (including the venturi/spraybar/muffler)? I ask because that sort of performance will definitely happen if it is too lean in level flight. That can easily happen with a smaller-than-stock choke area or a tongue muffler. Or. as may be the case here, the prop is too "draggy". It's not that the pitch is too low - since they routinely run very well with 3.75" of pitch and pretty good blade area - but that there is so much drag on the prop otherwise that it has to be run too lean. 

     Brett
  I would have to try the 10x5 MAS 3 blade again to go into more detail. It was lacking on drive and pulling power, I think because the blades are to narrow. My LA .46 has the Gardner piston & liner, and head kit, stock OS .283 venturi, .156 PA spray bar, Dinger tube muffler drilled out to .360, Sig P003 plug. I use Power Master GMA 10-22 fuel 4.5 oz tank 7+ minute run time in a clean 424. The plane weights is 50 oz, 60' lines, lap time 5.0 to 5.1
Al

Offline Brett Buck

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Re: 3 blade MA 10/5 propeller
« Reply #27 on: March 30, 2021, 11:09:27 AM »
  I would have to try the 10x5 MAS 3 blade again to go into more detail. It was lacking on drive and pulling power, I think because the blades are to narrow. My LA .46 has the Gardner piston & liner, and head kit,

  Does the liner have the factory stock timing?

     Brett

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Re: 3 blade MA 10/5 propeller
« Reply #28 on: March 30, 2021, 01:15:50 PM »
  Does the liner have the factory stock timing?

     Brett

Brian Gardner mentioned in a post a few years ago that his LA46 piston/liner sets would have the "stunt timing" numbers of his ST.51 setup.  His ST.51 setup is 126/138.  Brian listed the the stock LA46 timing at 142 exhaust and 116 transfers.

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Offline Brett Buck

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Re: 3 blade MA 10/5 propeller
« Reply #29 on: March 30, 2021, 01:21:40 PM »
Brian Gardner mentioned in a post a few years ago that his LA46 piston/liner sets would have the "stunt timing" numbers of his ST.51 setup.  His ST.51 setup is 126/138.  Brian listed the the stock LA46 timing at 142 exhaust and 116 transfers.

https://stunthanger.com/smf/open-forum/la46-abc-piston-liner-sets/msg457627/#msg457627

  OK, that makes sense -  greatly reduced blowdown makes it have to run too lean at the required RPM for the prop Al was trying. 

    Brett

Offline Al Ferraro

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Re: 3 blade MA 10/5 propeller
« Reply #30 on: March 30, 2021, 07:57:20 PM »
  Does the liner have the factory stock timing?

     Brett
  I never put a LA 46 on the degree wheel. I did check the LA .25  stock vs Gardner and they are the same timing.
Al

Offline phil c

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Re: 3 blade MA 10/5 propeller
« Reply #31 on: June 24, 2021, 05:53:29 PM »
That’s a lot more work than clipping a 1/2 inch off of each blade on a 11x6, which is easy to do with the square shape of the blades. I even tried one of those fancy carbon 11x4.5,  3 blades and my prop performed better and it only cost $10.
Al

Totally agree Al.  The 3blade 11/6 is a bit to much for the LA 46.  Cutting it to 10.5 worked for me also with an ENTIRELY stock engine including the muffler.  The motor runs better with the stock muffler.

The ENTIRELY stock LA 40 will run fine with the  10/5 on a Smoothie.  It seems to prefer a 4 cycle run with some modest rpm pick up in the manuvers.  The LA 40 also runs best on the stock muffler.

On either engine(this is a one sample test)  the stock NVA works pretty well but it does need a piece of silicon tubing to seal it to the spring area.

Regarding MAS prop pitches, a long time ago their website had a little explanation of the pitch on these "new" props.   They are designed to the prop airfoil true chord for pitch.  The pitch chord line runs from the leading edge to the trailing edge.  The airfoil is a true airfoil so it projects a little bit below the design pitch line.  It's mostly a flat bottom, so it measures a lower pitch on a simple pitch gauge.
phil Cartier

Offline Air Ministry .

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Re: 3 blade MA 10/5 propeller
« Reply #32 on: June 24, 2021, 06:39:49 PM »


youcan seethis biggerhere : http://www.aerodynamics4students.com/propulsion/blade-element-propeller-theory.php + feorey .

essentially , the pale blue line is Mr Prather . Which aint ' Pitch ' . So Theyre All Wrong ! for the last 50 years .  LL~ S?P VD~

the THIN BLACK LINE , = Entry Point to Departure Point - is true Pitch . BUY the rounded L. E. allows a degree of variation in ' seperation point ' of entry flow .
So is not neccessarilly the actual working seperation point . Though usually / ordinarrilly , its within coo-eee . And for practical purposes is the ' True Pitch ' blade X section ' true datum ' for MEASUREING .

Not the flat flank aft underside , unless a totally flat underside sharp entry prop airfoil . or a totally flat section .

=========================================================================




Offline Dan McEntee

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Re: 3 blade MA 10/5 propeller
« Reply #33 on: June 24, 2021, 06:55:24 PM »
   A little history on the MA 10-5 three blade I forgot to mention is that it was through the efforts of a Stunthanger member that they exist. I can't remember the gentleman's name, and I think he has since passed away, but he had contacted Windsor Propeller about making these and they agreed to tool up for it if he could come up with enough orders. He posted about it on Stunthanger and took orders. I got a few from him at the time and I liked how they worked with .35 and .40 sized engines. I guess sales were good enough that MA has kept it in the product line and even offer a left hand version. Maybe they are useful as a quad copter prop?  I can't seem to come up with the correct key words to search out that thread but I'm 99% sure it was some one who was a member here.
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Offline Steve Helmick

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Re: 3 blade MA 10/5 propeller
« Reply #34 on: June 27, 2021, 12:19:17 AM »
MAS does not make a 11x5 3 blade. The MAS 11x6 weighs 1oz and is 1/2oz lighter than the APC 12.25 x 4.75.

While we're on the subject, please note that APC doesn't make a 12.25 x 4.75. They do make a 12.25 x 3.75!

Despite a lot of folks bragging on that one, I've seen a lot of sagging lean runs with them. I have trimmed them down to 11.5", reshaped them in various ways, and used them on .46LA and also piped AAC .46VF with decent results. If the engine is too lean, nobody's happy. I'm also a fan of boring out the stock OS muffler about as big as possible. This makes the engine pump better, acting like the venturi is bigger, burning more fuel and more oil to run cooler. Read Randy's pinned topics at the top of this forum if you don't think so.  y1 Steve
"The United States has become a place where professional athletes and entertainers are mistaken for people of importance." - Robert Heinlein

In 1944 18-20 year old's stormed beaches, and parachuted behind enemy lines to almost certain death.  In 2015 18-20 year old's need safe zones so people don't hurt their feelings.

Offline Dan McEntee

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Re: 3 blade MA 10/5 propeller
« Reply #35 on: June 27, 2021, 08:30:19 AM »
While we're on the subject, please note that APC doesn't make a 12.25 x 4.75. They do make a 12.25 x 3.75!

Despite a lot of folks bragging on that one, I've seen a lot of sagging lean runs with them. I have trimmed them down to 11.5", reshaped them in various ways, and used them on .46LA and also piped AAC .46VF with decent results. If the engine is too lean, nobody's happy. I'm also a fan of boring out the stock OS muffler about as big as possible. This makes the engine pump better, acting like the venturi is bigger, burning more fuel and more oil to run cooler. Read Randy's pinned topics at the top of this forum if you don't think so.  y1 Steve

     I think the OS .40 VF and .46 VF are what the APC 12.25X3.75 were developed for. Ted Fancher related the story a couple of times on the forums about the visit to the parent company regarding an off the shelf prop for the early piped engines. I agree with your muffler assessments also. If you can't exhaust, you can't intake! I like to cut the stinger off the mufflers and just get it out of the way! A local club member had an "Aha" moment when he changed the tongue muffler on his LA.46 out for a tube type muffler. I warned him that it would make the engine run different, but that he would like the change!! He was surprised on his first flight that the engine ran out of fuel before he finished the pattern, and that he needed about an ounce more fuel to do so. We need more light weight tube type mufflers in the world! I don't know if Scott Dinger is still making his, and I don't know if Randy is making his any more. If you need the nose weight, the stock units will do if you relieve them a bit. If you absolutely must have a tongue muffler, make a lot of big holes in it!!
   Type at you later,
    Dan McEntee
AMA 28784
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Offline Brad LaPointe

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Re: 3 blade MA 10/5 propeller
« Reply #36 on: June 27, 2021, 08:11:04 PM »
If you want a good fairly light muffler for a LA .46 scrounge up a M 251 Enya muffler from an Enya SS .30 . 45 grams with the mounting bolts . The Enya is a great engine also , swap meets are a good source of things like this.

Brad


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