Triangle Math For Complex Shields


Ok, so my shield is a curvy mess. It is not a shape that has an easily found area, so that kind of puts me at odds with a lot of rules marshals. Due to the whole, "Rules" thing and having to follow them or whatever.

HOWEVER, I have found a solution. Here it is:

Step 1: Measure the perimeter of your shield, measuring curves wide (so that you err on the side of thinking it's too large and NOT breaking the rules as opposed to measuring too small and BREAKING the rules). Mark the points that you measured on so that you can come back to those same points later. You will need them!

Step 2: Draw a shape that roughly represents the shield. The lines don't really have to be to scale, it's just so that you can visualize what you're doing.


See? It's totally not to scale at all.

Step 3: Make all of the areas within your shield into TRIANGLES and label the areas inside.


Step 4: Use you marks from before to measure the lines that have unknown values in your triangles.

Step 5: Now, go to and add in all the values for your triangles. It will calculate that for you. Because we guestimated some of our curves, be sure to ROUND UP on any of the calculations!!

a: 130
b: 170
c: 45
d: 90

Step 6: Total up your areas and know that you're pretty darn close. If you find your numbers getting super close to the area cut off or that you've gone over by a small amount, make sure your measurements are right, and then go back and measure your curves with more angles. All that fibbing towards being legal probably shorted you a few inches.

Total area: 435 square inches

Step 7: Write that stuff on the back of your board and go drink a beer (or a nice soft beverage), because you have earned it.


I'm just curious as to how you were doing it before that.


Mainly I was trusting the math of others, and not actually owning a shield.