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ISO Frank Orlic's Prop. Pitch Gage

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TomGracey

Well-Known Member
Joined
Dec 5, 2018
Messages
466
Like to find a Frank Orlic's Prop Pitch Gage anyone have one they could part with or could supply me with some of the dimensions for the pin center locations so I can machine my own. And if anyone can e-mail a copy of his instructions an pitch charts it would be much appreciated mail to [email protected]
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No need for the pitch tables.

Take 360 divided by the degrees you rotate the prop x dial reading. So 360 / degrees of rotation x dial reading.

If you think about it you're just measuring the distance the prop would advance (pitch) over a fraction of a complete revolution. So divide that by 360 and you get the pitch over a full rev.

I measure everything at 75% from the C/L. You can sweep the whole blade and take an average but I like to do the 1st 15* of the LE and the last 15* of the TE. The LE number will tell you ultimately how fast the prop will go. MPH = (RPM x LE pitch) / 1057. The TE number or "progression" tells how well a prop will stay "hooked up" and not want to come out and make the boat hop.

ie: the dial moves 0.180" over 15*.

360 / 15 = 24 x 0.180 = 4.320" pitch
 
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