anyone good at math? cut Benders wall stone into pie slices - how to calculate the angle?

[tuut]

hello
I am going to lay an edge with Benders mursten antik in a quarter circle!
Radius 2.17 m and I am now wondering how I should calculate the angles I need to cut on each end of the mursten 35 cm long, 21 cm deep, 14 cm high

any math expert

 

[thomasx]

Five degrees.

 

[tuut]

dare one ask how you came to that conclusion?

 

[thomasx]

Eyeball it a bit

Just kidding. A radius of 2.17 gives barely 3.5m "circumference" on your quarter circle 2PiR/4. So you'll need 10 stones. 90 degrees is the angle in a quarter circle, which means 9 degrees in each section, but there are two stones meeting, so half the angle on each end of each stone. That is, 4.5 degrees to be exact. Say five degrees to give you some wiggle room as well

 

[tuut]

I might be a bit slow... What is the angle at A / B / C / D ?? See image ...

 

[thomasx]

Angle A, you need to decide whether you want it to be right or not, depending on whether the first stone should lie "straight" or at a slight angle. Then it's about 5 degrees, or about 85 degrees, depending on which of the two opposite angles you're measuring. Now you have marked a stone with white and only pointed to the tip B, so I assume you mean the angle that then becomes 85 degrees. On, for example, a saw, you would set it to 5 degrees since it is 5 degrees off from the right angle.