Propeller pitch measurement tool.

[waraton]

This in use at my local club on a Warp Drive prop yesterday. The bubble wheel device is over 20 years of age and with digital variants now available I was curious to know what tool is most popular today and where they are available.

[RossM]

Hi,
I am no prop adjusting expert.
There are plenty of those wheels in use today
Bolly make one, retails $60.00 I think.
http://bollyaviation.com.au/wp-conte...uge-instr1.pdf

I see your local club has a "N" registration number on a gyro

[RossM]

Also on Bolly's web site, in the manuals for Propeller's [ http://bollyaviation.com.au/wp-conte...structions.pdf ]


The cheapest method of all is a straight stick and remembering that 1 degree is One in Sixty.

This basic navigation rule that all pilots should know also works for propellers.



A nice flat (ground) surface helps but quite often a simple comparison from blade to blade is all that counts.

This method uses such big lengths any small discrepancies are less important. To explain ...

If your propeller is sitting square to the ground (ie you have lifted the tail or nose so that the prop flange is at 90 degrees to the world, then the blade will be sitting at an angle to the ground. Call it an angle of attack if you want! See diagram

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Set the first blade horizontal. Make a mark on the stick so the next blade can be set the same.



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15 = 300. Make a mark on the ground 300mm away from the Origin point. We call it the Focal Point. Make sure it is the in the correct direction.

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If we wanted 15 degrees of prop pitch, then using the 1 in 60 rule, then we have 20 units x it gives fewer problems with the twist of the prop.

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Nip up the bolts and turn the prop to the next blade and repeat the last step.

This method is so simple, no one thinks it is good enough. In the field one is normally simply trying to slightly increase or decrease the pitch and to make all blades the same. In this case use the stick placed against the angled blade to find the focal point on the ground and use this as your comparison or move it (focal point) slightly for any new setting of less or more pitch. In our above example, if I wanted 1 degree more pitch then I would move the focal point 20mm away from the origin, and so forth.

[RickE]

This is what I use and works well

[tonydenton]

struth ROSS, that is a " mills and boon" . you obviously had another FRIDAY off ya bludger.

[RossM]

Yes Tony, and good to see that you are at work on the weekend as well.