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I’m rather new to this forum, so I may not have found all relevant messages, but although various ways to produce a fret board with compound radius are discussed, thusfar I missed a proper way to assess its various dimensions. Therefor I recently made the attached selfexplanatory spreadsheet based on the fret board surface being part of a cone. With it all f.b. dimensions can be calculated by entering the required width and radius at the nut, width at another point along the f.b. and scale length in the second column.
“Point” can be located at any distance from the nut, both along and beyond the fret board. The latter being usefull to determine the radius at both ends of a routing- or sanding jig used to create the curved f.b. surface. (To that purpose distances beyond the nut should be entered as negative values.)

I'd be curious to see that but can't find the attachment. Am I missing something? Thanks.

Also, for what it's worth, compounds don't necessarily have to be conical.

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Sorry, view the message "The extension xls is not allowed", apparently it is not possible to attach an Excel file. Does anyone know how to solve this ?

Sounds like an interesting spreadsheet calculator!
Would be cool to write a formula comparing the vertical distance between a simple radius and a cone (aka compound radius) fretboard at any given point.
Also the maximum distance between the two and at what XY point location.
I'm guessing that it would be very minimal.
The reason I say this is that I (as well as others, I'm told) radius the fretboard to a simple radius but level the installed frets by hand to a cone approximation.
Doesn't seem like much material is removed from the fret tops in this process.

Nelson

Anyone know why the software doesn't allow a *.xls file to be uploaded?
Security?
Thanks
Nelson

Interesting mathematical question for sure, but I would ask how many of you shape necks/fingureboards to exactly measured criteria versus shape it until it 'feels' right? ON my first build I just got a rought shape and then whittled away until the neck and finger board just felt right along the length and low and behold the actual shape had a very slight V profile at the headstock end and flattened out towards the body as the neck tapered out... I guess ensuring that there was probably the same volume of wood under your hand whether its positioned on the neck and it did feel very comfortable to play.... so just wondering how others go about it? I appreciate it's alot different for us amateurs mostly just building for ourselves as opposed to customers but still an interesting thought?

Another point would be- when whittling away to get it to feel right - the final dimensions where 2 -3 mm less in neck depth than say in the Kinkade OM plan (although partly due to the mahogany used being a bit thinner that anticipated - a result of getting it square ) yet somehow it turned out good.

Frank, I think that Henk in his initial post above was talking about the fretboard radius.
As far as the shape of the neck shaft, a template can sometimes be a good thing.
A template taken from a neck that you feel comfortable with can help ensure that the same profile is transferred to a neck being carved.
It's not difficult to make epoxy templates at, say, the 3rd and 9th frets to establish the contour.
Nothing wrong with your method of carving by feel either.
Nelson