Prop for your 1/2 vw engine

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Rockiedog2

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props are a black art...Propman's half Vdub props are near toothpicks and pull like crazy. Nowhere near the chord of either the Culver or Tenn and much lighter than the ones I've weighed.
 

N8053H

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props are a black art...Propman's half Vdub props are near toothpicks and pull like crazy. Nowhere near the chord of either the Culver or Tenn and much lighter than the ones I've weighed.
What is the length and pitch of said props? But statements like "pulls like crazy" are meaningless.

Using the culver over the Tennessee. With the culver I lost 10 mph in cruise. It also took 3000 rpm's before the airplane would even start to roll. With the Tennessee prop at 2000 rpms I am moving. I should also note this prop is being used on a 600 lbs airplane. This weight is wet with pilot.
 

TFF

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Unluckily numbers only compare between same brand. Each prop builder pitches different and calls them different. 5 for one is not the same 5 for the other. The funny thing to is put the same two props on a different airframe and the better prop can switch.
 

Pops

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Unluckily numbers only compare between same brand. Each prop builder pitches different and calls them different. 5 for one is not the same 5 for the other. The funny thing to is put the same two props on a different airframe and the better prop can switch.
Very true.
 

Rockiedog2

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What is the length and pitch of said props? But statements like "pulls like crazy" are meaningless.

Using the culver over the Tennessee. With the culver I lost 10 mph in cruise. It also took 3000 rpm's before the airplane would even start to roll. With the Tennessee prop at 2000 rpms I am moving. I should also note this prop is being used on a 600 lbs airplane. This weight is wet with pilot.
well, "pulls like crazy" isn't meaningless...it means "pulls like crazy". Come on, man. LOL
If you want specifics I can give you that too. I was just being brief. I tested a number of different props on my Legal Eagle. Tennessee and Performance primarily but there were others. The Performance by far outperformed the others. Best was a 5420 thin camber blade that climbed 865 ft min and would blow the max Part 103 speed away. Takeoff averages about 100 feet and 2-3 seconds. That on a 45 horse Casler on a 243# airplane. It has to have a restrictor plate to be legal. I got lotsa test data around here somewhere...in my experience(objective) nothing could touch the Performance Props. And they got that skinny little racer looking blade. Go figure...
 

N8053H

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I have a buddy who wants to make me a 52x28 prop. He uses winglets type of tips on his props. I hope he does this. I would like to try such a prop and report what I find or the performance I get from such a prop.
 

Rockiedog2

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Scott Casler recommends a Tennesse prop over all others. I had already purchased or ordered the culver when he told me this. He said stick with a 54x24 Tennessee prop. Just what I did.
Yeah I know that's what he recommends that's why I got a Tennessee first.
He's good but he doesn't know everything...none of us do...I'm speaking from extensive careful test results. I doubt Scott has ever done a side by side formal comparison test Tenn vs PP.
But shoot Tony run whatever you want man I'm not trying to sell anything here I'm just passing along what I learned FWIW
 

N8053H

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This is what this thread is all about. Finding what works and not what someone wants to sell you. As to Scott knowing everything. He knows way more then I about these vw engines. So far everything he has told me has been right on the money. But I would like to experiment with a few prop designs so others can learn as I do without going through the expense to see what works and what does not. I would say if the prop pulls a 600lb. airplane through the air it should perform just as good or better on a lighter weighed airframe.

If I get another prop say of the 52x28 design, I will post the info as I get it, along with pics.
 

N8053H

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Unluckily numbers only compare between same brand. Each prop builder pitches different and calls them different. 5 for one is not the same 5 for the other. The funny thing to is put the same two props on a different airframe and the better prop can switch.
The Tennessee prop was stated to be a 54x24. The culver was stated to be a 54x24. So these two props are being called the same. Meaning 54x24. As a experimental airplane owner what else could one ask to get this right or the correct prop. Why I posted or started this thread. To show two props called the same are not really the same.
 

Turd Ferguson

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The Tennessee prop was stated to be a 54x24. The culver was stated to be a 54x24. So these two props are being called the same. Meaning 54x24.
That doesn't mean they are the same. Every prop carver measures pitch a little differently. There is no standard way of doing it.

I think you do better telling them what kind of plane you have, how fast it goes and what kind of engine. They should have a pretty good idea of what you need. Order by length and pitch and you might not be happy.
 

Rockiedog2

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That doesn't mean they are the same. Every prop carver measures pitch a little differently. There is no standard way of doing it.

I think you do better telling them what kind of plane you have, how fast it goes and what kind of engine. They should have a pretty good idea of what you need. Order by length and pitch and you might not be happy.
I'm with Turd.
tell Propman what you got and what you want it to do and he'll pretty well know what to build. And he'll recut it once to get it just so if necessary...or that's what he used to do I haven't bought one in a while.
Otherwise it's trial and error
 

TFF

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A prop party is always a good thing to try and have. Friends bring a prop and you try it. Then even if not what you want you can get static rpm numbers with size and see if a modified version of what was tried will be the one. Without previously building a prop for an exact airframe, it probably takes 3 props to get it dialed in perfect. Where you cut that is up to the wallet.
 

StarJar

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A prop party is always a good thing to try and have. Friends bring a prop and you try it. Then even if not what you want you can get static rpm numbers with size and see if a modified version of what was tried will be the one. Without previously building a prop for an exact airframe, it probably takes 3 props to get it dialed in perfect. Where you cut that is up to the wallet.
Heck that's a great idea. Maybe we can make Airventure one big prop party!
 

N8053H

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While all good idea's. It's hard to find people that have a 3 1/8th bolt pattern on their prop. This is what all Hummel engines use be it full or 1/2. All other vw engines manufacturers use a 4 inch bolt spacing.
 
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