Box maker to make boxes without right angles

I want to make a tabbed box but the sides won’t be all 90 degrees maybe like a triangle box or something. I noticed that if i put .75 tab length in the solid version of the shape isn’t .75. What do I need to know to draw tabs around a shape in cad so I can have it fit together?

I don’t know if it will work for you, but there is a box maker in Easel that worked really well for me. I tried it at first with a 1/8" bit and that didn’t work as the joints were too loose. Then I switched to a 1.2mm bit and that worked great. Really tight joints.

I don’t think there is a app to do what i want. Im fine with regular tabs Imagine a box with a octagon top and bottom or a star or something beside a square or rectangle. If i draw the shapes what is the math for making tabs. do you start in one corner and rotate clockwise or something?