Jay Pique wrote:
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So I've got one big plank of walnut out of which I'd like to make a
round table. I've determined that since the plank is 12x96 I have
1152 square inches of area, which equates to just over a 38"
diameter
table, (ignoring the realities of loss due to saw kerfs and the
aesthetics of infinitely narrow strips.) Now assume that I rip the
plank into 3 strips of 4" - what's the biggest diameter I can get?
Is
there any sort of formula I can use to see what my options are?
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It's paper doll time, AKA: Graphical solution.

You are going to want to cut this 12"x96" piece into three (3) pieces
that are 12" wide but of varying lengths.

The lengths will be determined by graphical layout using some graph
paper and 1/4"=1" scale.

Assume you want to get a 36" finished dia. top,cut the first blank
37"-38" long.

If you joint and rip this board, you should yield three (3) pieces
that are 3-1/2" wide which yields a 10-1/2" glue up.

You might get lucky and get 3-3/4" pieces, thus an 11-1/4" glue up.

The 2nd piece will be about 32"-34" determined by graphical solution.
(Allow 1/2" min on each end for enough waste when trimming final blank
to size.)

Rip and joint two (2) pieces say 5-1/2" to 5-3/4" each.

Place one board left, the other right of center board and glue-up.

The 3rd piece will be about 18"-20" determined by graphical solution.
(Allow for enough waste when trimming final blank to size.

(The 18-20 is strictly a guess, but it is in the ball park)

Rip and joint two (2) pieces say 5-1/2" to 5-3/4" each.

Place one board left, the other right of center board.

Finally, there will be a 4th piece which will be short.

Plan this closely since you will be near the edge with a short piece
and you are running out of material.

May want to rip into 2-1/2" strips and then add to glue up.

The above will allow the glue up in stages, not the hole thing at
once.

When glued up an cured, head to the commercial drum sander and sand to
size, then trim with a router and a circle template..

Have fun.

Lew