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Complex Curves inside profile suggestions.

Joined
Oct 21, 2024
Messages
14
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9
Location
Springfield, Ohio
I'm about to make a decisions on the inside profile or the bowl I posted earlier - for fixing the bottom;

"oop someone drilled a hole"

For the fun of it and my learning I have closely measured the current outside profile and sketched it on graph paper full scale. I've also include the hole in the bottom (mistake not fixed yet) and the current dashed inside for reference leaving a lot to work with. Although not likely, it might be nice if the inside profile did not hit that hole.

My thinking for the inside profile is to somewhat follow the upper concave part at ~ same thickness or getting slightly thicker as going down. Around the transition to convex outside this would gently transition curve to across the bottom similar a normal bowl. Seems like the transition from upper "outward" inside profile to the more common bottom profile should be slow. Alternatively, since curve transitions are sometimes abrupt, it could follow the outside more closely with a more sudden transition at the inflection. Not sure on the final bottom thickness. (this will need the plug mentioned above and in the other thread.) Most of my walls are 6-10 mm. Seems like this bowl might want to be thicker however I'd rather not have it feel "too heavy". (4 1/2" ht, 7" diam. Norway maple )
(note the wood figure looks much better than the photo as my tool marks are still prevalent).
Thanks
Lary
 

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  • Crotch profile_IMG_8042.JPG
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  • Bowl Crotch B cross sec.jpeg
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I think the full size drawing on graph paper is a wise move. First decide on the wall thickness. Then I would sketch in an inside curve that mostly follows the outside curve. At the "corner" between the side wall and bottom I think you're not going to be able to follow the outer curve as exactly, hence the wood will be thicker there. Don't know whether wood movement will be a problem with the varying thickness.
 
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