prop bending 101

[Duke]

sorry to resurect a old tread, but what does yamaha mean when they say the pitch on the prop is 19.9 degrees ?????? wanting to tweak a stock prop and need to know where to start......

Absolutely nothing.

[big john]

thanks Duke, and i just saw a typo the stock prop is 15.6 degrees so it looks like i will be calling you to get some hints ??????

[westy]

Hi Guys im realy lost trying to accurately measure a prop with my Watcon Prop Gauge im unsure where to start the trailing edge of the prop on the gauge..
i have supply'd 3 Pictures to explain , First picture show's what looks like the prop measuring 22 degrees for around 2 1/2 inches of the blade
but when you move the gauge around still measuring the same blade to where Duke is measureing his prop in his picture from the start of this thread my prop measures 24 degrees for about 1 1/2 inches

regards Robert

[skoepp]

Hi Guys im realy lost trying to accurately measure a prop with my Watcon Prop Gauge im unsure where to start the trailing edge of the prop on the gauge..
i have supply'd 3 Pictures to explain , First picture show's what looks like the prop measuring 22 degrees for around 2 1/2 inches of the blade
but when you move the gauge around still measuring the same blade to where Duke is measureing his prop in his picture from the start of this thread my prop measures 24 degrees for about 1 1/2 inches

regards Robert

The props are progressively pitched.
THere not usually the same pitch all the way down each blade.
Therefore you have a different pitch angle depending on where you are measuring the prop.

[westy]

The props are progressively pitched.
THere not usually the same pitch all the way down each blade.
Therefore you have a different pitch angle depending on where you are measuring the prop.

so looking at my pictures what is my prop pitched at ???? p.s thanks for the quick reply

[skoepp]

so looking at my pictures what is my prop pitched at ???? p.s thanks for the quick reply

Looking at the gauge the pitch on trailing edge is 22 degrees with maybe 22.5 to 23 on very tip of blade.
Its definetely not 24 anywhere on blade by looking at your pics.
But as you go up the blade you do not have 24 degrees it goes the other way.
More like 20 degrees. And as you move further up the blade the pitch will continue to decrease.


If you look at Dukes pic, which is hard for me to see real good, I see the pitch being 24 degrees with maybe a tade more pitch on very end of blade.
I do not know this thread so i have not read anything before this page so may be way off.

[beerdart]

Where you measure is not important as long as you measure the same spot every time and then use the number as a reference for pitching. Most measure aprox 1"-1/12" from the tip of the trailing edge.

[Duke]

Hi Guys im realy lost trying to accurately measure a prop with my Watcon Prop Gauge im unsure where to start the trailing edge of the prop on the gauge..
i have supply'd 3 Pictures to explain , First picture show's what looks like the prop measuring 22 degrees for around 2 1/2 inches of the blade
but when you move the gauge around still measuring the same blade to where Duke is measureing his prop in his picture from the start of this thread my prop measures 24 degrees for about 1 1/2 inches

regards Robert

Just measure the bottom of the blade up to about 1 1/2". The blue mark is 2". Yours is much less then 24 degrees. just turn the gauge till you get the closest for the longest on the bottom side starting at the tip. Hope that makes sense.

I'll take some better pictures next week.

[pwcdaddy]

my wave venture has crappy holeshot-top end is great, will tweaking the leading edge of impeller really help the holeshot? i haven't looked at it other then to inspect condition and clearance. Brushed through this thread and thinking I will look at doing this in march when the weather is warmer. i'm not even sure what is in there but i assume it is the stock unit, does anyone know what was installed in these from yamaha? It's a 1996 wave venture 1100. Thanks so much, pwcdaddy.

[Duke]

my wave venture has crappy holeshot-top end is great, will tweaking the leading edge of impeller really help the holeshot? i haven't looked at it other then to inspect condition and clearance. Brushed through this thread and thinking I will look at doing this in march when the weather is warmer. i'm not even sure what is in there but i assume it is the stock unit, does anyone know what was installed in these from yamaha? It's a 1996 wave venture 1100. Thanks so much, pwcdaddy.

Its possible but most likely your liner and or OD of the prop is worn and needs replacing. Check the clearance between the prop and liner first.

[pwcdaddy]

Duke, thanks for the answer. Might you know what that clearance should be. The manual that I downloaded (was supposed to be a genuine wave venture) doesn't have it, doesn't have much info actually. It turns out I bought a collection of diagrams and torques specs, and thats about it. Thanks again pwcdaddy.

[Duke]

Duke, thanks for the answer. Might you know what that clearance should be. The manual that I downloaded (was supposed to be a genuine wave venture) doesn't have it, doesn't have much info actually. It turns out I bought a collection of diagrams and torques specs, and thats about it. Thanks again pwcdaddy.

Should be around 10thou.

[pwcdaddy]

Ok thanks

[wpage]

Cool ideas...

Is there a service to do this professionally?

[Weber Guy]

Hi Guys im realy lost trying to accurately measure a prop with my Watcon Prop Gauge im unsure where to start the trailing edge of the prop on the gauge..
i have supply'd 3 Pictures to explain , First picture show's what looks like the prop measuring 22 degrees for around 2 1/2 inches of the blade
but when you move the gauge around still measuring the same blade to where Duke is measureing his prop in his picture from the start of this thread my prop measures 24 degrees for about 1 1/2 inches

regards Robert

Robert,
Looking at your photos shows the trailing edge at almost 24??, so these images show your finish pitch is approx 23.9 ??. You will have to measure the leading edge to get a rough idea of your overall pitch. Contact John at [email protected] for more detailed technical support.

Regards,
Randy