Design of a new object/product - Modified "Constrained Ball"

Design of a straight line drawing tool, new concep

Hi. I have modified the design, evaluating the angle of inclination, I have carried out a consultation and construction with the technical diagram of the ball point of a pen. In this way I can determine that the 40 ° angle is the maximum optimal angle for the pen to work. The design has been modified to meet this parameter. It is also possible that this designed device can be used with a mechanical pencil or pencil, in this case the angle can be increased, but the pen does not work optimally. For this reason I believe that the concept can work with all three types of writing products. I await your comments.