Constrain by surface area in Fusion 360 I'm trying to create a sketch that is constrained by surface area. In my model I have a relatively irregular, flat area that I would like to constrain by area so that it never exceeds a certain number. There are a lot of other constraints for angles, lengths, points, lines and the area of a surface is also always available in the properties. As a rather new person to Fusion 360, it feels logical a constraint by surface area should be possible. Am I missing something or is there a good reason why this constraint doesn't exist?

After some testing, Fusion does have a category to put in an Area parameter [edit -> Parameters ->] for Area that takes measurements in acres and _circular mil_ but no useful measurements such as square centimeters or square inch. One _circular mil_ is defined as a circle with a radius of 1/1000 inch, or 0.0254 mm, for an area of $5.067×10^{−4}\text{ mm}^2$.

However, defining the area of an item isn't (currently) straightforwardly possible: areas are not defineable, and with the obvious lack of possible parameters (square metrics and anything but super tiny or super huge) it doesn't seem to be planned. The best you can do is for bodies that you know the formula for the area in the following fashion:

![enter image description here](

Here, the left measurement (d2) is 1 mm. The parameter area is 10000 circular mil. Since we know A=d1*d2, we can go A/d2=d1 for a rectangle.