John D. Williams

Wood Turnings for Connoisseurs 

Kelton entry angle calculations Page 2

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Just in case you need a concrete example. Here is a maple blank. Total thickness 5.5 inch I will make three bowl blanks and one core (I drew an extra line but ignore that as there was not enough room to make it.)
Here the ruler joins the point on the edge to the 1.5 inch deep mark.
Use the adjustable protractor to get the angle described by the tangent to the circle at the intersection of the ruler and the circle and the ruler held parallel to the face of the bowl.
Transfer the angle to the Kelton knife entry angle.
Here the core has been removed.
Checking the calculations and I am a little over my estimated depth but by less than the width of the cut. So all is still good.

And another example in some walnut. This walnut was 6.5 inches thick with a circumference of 17 inches.

Another bowl but a deeper one. The first cut will be 3 inches deep and lined up with the inner circle.
Here is the entry angle as described by the tangent at the blue smudge and a line from that to the 3 inch depth. So I hope you have found these instructions useful and thus have reduced the number of inadvertant funnels in your stodkpile of drying forms.

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