Kind of Wood Grain

How to achieve wood grain as expected?
Tree grows so there is annual rings inside.
When there was low humid then the tree will grow slower higher density so the color will be darker.
And when there was high humid then the tree will grow rapidly, lower density, so the color will be lighter.
Contrast color of each growing year to year we call it annual ring.

Wood plank's grain will be appear according to how we rip the log.

Plank no 1 will generate less grain. Since tree grow in cone shape then the grain will be curve at it's end. We call it tangential grain.

tangential grain

 Plank no 2 will generate more grain. We call it radial grain.

radial grain

Wood percentage conversion from log to clean nett component

The conversion refers to a percentage comparison yield netto volume of wood against the volume of logs

 Case:
 Log diameter of 40cm, 2 meters long, we will convert it into clean planks 25mm thickness.
 There should be additional +/- 5mm as spelling planner / thicknesser. So that the output of sawmills ripping  must be set to 30mm.
 It should be noted the thickness of the saw blade also create a space that reduces yield, typically about 5 to 10mm.
 another factor is the log bark. usually at the beginning of the cutting should be disposed of +/- 2cm

The calculations are as follows:
 Left image shows rough volume of log = 40cm diameter x length 2m = 0.2512m3
 middle image shows how to rip at sawmill
right image shows results rough cut (of sawmills) = 0.1761m3

 Then output percentage from sawmill will be = 0.1761: 0.2512 x 100% = 70%

 Furthermore, after do planner and thicknesser, 30mm of board thickness should be 25mm, so the planks volume will be 0.1467 m3, the yield is 58%.

 please note this 58% figure is the most that can be achieved because it uses the illustration of a full round log, while in reality the log must be irregular shape.
 They can be reduced again by defects of wood, knots, sapwood, etc.

 Furthermore, again cutting into smaller components, we will not discuss here because so many variations. Just to keep in mind that the smaller the size of the components, the smaller output percentage anyway.

 Our experience shows the yield of teak are at 20-25%