Whenever I do export a cylinder type part into a stl, the side length of the triangles are really long. The triangles are from the top to the buttom of the cylinder. If I set the refinement smaller (angle and deviation), the height of the triangles get smaller but one side length stays over the whole cylinder length. How can I make my stl net more evenly?

While waiting for your *.sldprt file I experimented a bit more to get all triangles closer to same size.