The lighter color bamboo strip is from the same culm, note the change of color caused by tempering.  

 

Time to start final planing to interim dimensions on the butt section strips.

 

Two strips done.  

 

We now have tapered strips.

 

For every strip completed I note the measurements at every station. At this station I get an under read on both strips.  If the last four strips give me the same average under read of 0.001 I will set the station at 0.118 instead of 0.117 when going for final numbers.  

 

 

This diagram illustrates what is known as chasing the apex, something you do throughout the rough and final planing, although not necessarily to the same accuracy for the former. The left triangle is an equilateral triangle, enamel on bottom, apex on top.  The height of the triangle (vertical line) is the measurement set for every station on the form.  Having a 60 degree apex, which I was looking for when rough planing does not guarantee the other two angles are also at 60 degrees, and you may end up with strips that look like triangles 2 and 3.  Picture six strips like 2 and/or 3 at glue up time and you’ll end up with a wonky hexagone.  You can have shape 2 at one station and shape 3 two stations down on the same strip.  The word is measure often and correct early.  How do we get these wonky triangles?  Mostly caused by the person holding the plane.  A slight tilt of the plane here and there and bingo!  Could also be a node that is not totally flat on one side of a strip.  The foolproof method to see if we’re on track is to take two measurements as per the dark lines in triangle 1.  If they’re not equal, you have a triangle 2 or 3 to deal with.  I don’t worry about a 0.001 difference, above that, correction required. 

Isn’t this fun?????