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Here is a pdf file that Ralf sent.
Explanations to Pictures 1 and 2:
A = Bed
B = Cutter (60°)
C = Cam
D = Power Feed
E = Bamboo strip
F = Micro switch
G = Drive belt
The strip is inserted into the power feed (D), which consists of a number of rotating rubber pulleys. The Pulleys should be made with an adjustable spring mechanism, so they will fit different strips with various widths. The power feed is driven by drive belts with a motor with an adjustable speed.
When the strip passes the first micro switch (F) in front of the Cutter (B) the cam (C) which is located underneath the bed (A) will start turning. The motor which turns the cam has to have an adjustable speed as well. The cam will lift the bed/strip into the cutter as the strip is pushed forward by the power feed. The amount of height gained by the bed is dictated by the cam's shape. As soon as the end of the strip has passed the micro switch which is located behind the cutter the cam will stop turning - this means that both micro switches have to be connected to the motor of the cam to either turn it on or off. As you can see the cam has a very special shape, which has to be calculated according to the taper of the butt- or tip section. This means you have to have a cam machined in a shop for each butt- and tip section taper. You have to correlate the speed of the cam and the speed of the power feed. Exactly at the point when the front of your strip enters the cutter the cam has to start turning and exactly when the strip leaves the cutter the cam has to stop turning and should have made one full turn (actually not really one full turn - it has to turn from the lowest point of the cam to the highest point, I'm my picture this would be about 270°). Walter Brunner has solved this problem by installing a little green light which comes on, when the strip passes the first micro switch and which turns off when it passes the second micro switch. Just below this green light he has a little disc with a red dot painted on it. This little disc is connected to the cam and turns at the same speed. Another yellow dot is painted on the outside of the little disc. When he starts milling he aligns the two colored dots. Now the little green light comes on (when the strip enters the cutter) and the red dot starts turning. When the green light turns off (the strip has passed the cutter) the two colored dots should be aligned again (see picture 2). This is a matter of trial and error and it requires two motors with variable and adjustable speeds (one for the power feed and one for the cam). I didn't draw the hold downs for the strip (spring mechanism), so you have to add them as well.
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