this makes no sense to me ...

another day in paradise, or is paradise one day closer ?

The largest outside diameter of the splines on the shaft. Its really a very simple thing to understand. I have had zero luck searching for the information. The # numbers are the SAE aircraft prop shaft spline numbers. I really don't know how to ask, so you could understand it.
For large propeller installations the propellers are linked to the shaft by way of splines. And these shafts come in some of the various sizes that I have posted. Please tell me how I can ask this in a more understandable way?

Are you looking for the SAE spec?

https://www.sae.org/standards/content/as41f/previe...

No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
STF

From https://www.coursehero.com/file/p7ekk019/Notice-th...

"The sizes of splined shafts are identified by an SAE (Society of Automotive Engineers) number, SAE 20 splines are used on engines in the 200-horsepowered range; SAE 30 splines are used in the 300- and 400-horsepowered range, and SAE 40 in the 500- and 600-horsepowered range. SAE 50 in the 1,000-horsepowered range and SAW (sic) 60 and 70 are used for larger engines"

I'm curious as other references suggest #60 was used on Wright Cyclone engines. Are you building a B-17?

[QUOTE="SparWeb"] (Aerospace) 4 Oct 18 04:26
Are you looking for the SAE spec?

https://www.sae.org/standards/content/as41f/previe... [/QUOTE]

Nice print, but it has NO DIMENSIONS!
And the other link below ? All non accessible information? Did it have any dimensions? I know the applications for the splines I'm asking for.

I would guess the following couple of of Mil-specs contain the data (well at least to know what the SAE doc probably contains).
AND10529 PROPELLER HUBS-STANDARD DIMENSIONS FOR INVOLUTE TOOTH SPLINE CONTROLLABLE PITCH
AND10530 PROPELLER HUBS-STANDARD DIMENSIONS FOR STRAIGHT TOOTH SPLINE CONTROLLABLE PITCH

They can be found here
http://quicksearch.dla.mil/

Here's where to order it: https://www.sae.org/standards/content/as41f/ $78.00 USD

And huge thank you to (verymadmac)that is what I needed, very much appreciated.

Also... FYI...

AND10152 Shaft Ends - Propeller

NOTE. General involute spline dimensions: there are a few very specific 'other specs' for those.

Regards, Wil Taylor

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