Geodreieck (Set Square)
Instruction
Week 5 – Educational design or whatever you want to do
A “Geodreieck” is a piece of plastic that most students have to use in school to create different geometries in the math classes. It can be used to construct angles as well as parallel lines.
And it gets lost. Permanently. We always have one or two spare here at home, in case one gets lost.
So I thought about the idea that you could make a Geodreieck by yourself. And yes it works well.
Create a square. Now use a big rectangle which is rotated by 45° and the Combine->Subtract function to construct a triangle with one 90° and two 45° angles. Turn this by 45° so that the hypotenuse is at the bottom.
This is a great time to get used to the Array function of XCS. The grid array is great for the ruler and the parallel lines. Unfortunately XCS only supports a small number of repetitions. So create only one centimetre of the ruler, then select this and ask XCS to repeat this centimetre.
The circular scale that shows the angle can bei constructed by the Array -> Circular Array function. Just ensure that you move the rotation center (the x and y setting) a little bit away - exactly in the middle of the hypotenuse of the triangle.
I also used the array functions to ensure that the numbers are always at the correct place.
Next we have to construct the circular window. Create two circles around the 0 point (the middle) of the ruler. Choose combine, subtract at overlap to build a ring. Now we need a rectangle to cut away the lower part of the ring. (combine->subtract) and this gives us the circular window.
I grouped the circular window and the outer triangle into one layer that contains everything that needs to be cut and all the other geometries in a second layer that needs to be scored.
It was much faster than expected. Only 4 minutes. The F1 could be even faster because of the huge number of things that need to be engraved.