The firewood rack formula allows you to set the width, height and the depth of the rack. The pieces that make up the rack automatically size accordingly. The images blow give 4 examples of different width's and depth to show some of the formulas capabilities.

4 foot long

6 foot long

8 foot long

8 foot Long x 4 foot wide

Videos

In the timed step build video it show the rack being assembled on piece of lumber at a time.

The rotating firewood rack shows a 3D rotation on the Z axis of the firewood rack.

The Technical Stuff

If you are new to MathCompiler3D on the left-hand side of the application there is a project tree. The project tree has 3D Worlds, Slates (screens of math equations), Permutations, Targets and C# classes. In this section the focus will be on the Slates and the math used in making a parametric firewood rack.

Slate - Lumber Dimensions

Lumber dimension are standard sizes of wood. Although you can use any scale desired, the projects on the web site In MathCompiler3D defined and inch as 1 / 2 which = .083333. A unit of one is a foot. If you add a box to a 3D world. A common use of these equations would be to add a box to your 3D world, right click on the answer for PlyWood34 equation which is .05989583333...goto set object dimension and set height. This makes a 3/4" of plywood thickness to your 3D without making a target connection out of the equation to the 3D object. A target is when you assign the result of an equation to a property of a 3D object (X, Y, or Z physical position) or a specific target of a 3D object like width, height, or depth. Then when F6 is pressed, the math equations across all slates are recalculated. The equations that have 3D targets then have the value applied to them and the new view is rendered in the 3D world.

Slate - Control Panel

The control panel slate holds the primary variables for controlling how the wood rack is rendered. W₁ (W subscript ₁) controls how long the rack is. 

D₁ controls the depth of the wood rack

H₁ controls the height of the wood rack

Summation

There is no end to the level of detail that you can add to a 3D formula. The greater the engineering, the more you can do with it, but the time to create it increases. Usually I find that extra engineering is beneficial. If 9 ways don't work and your presentation is coming up - have the 10th one ready. That being said, the level of engineering of a formula is a judgment call. If you need it, don't hesitate to put the time in, if you don't, then simply communicate the conceptual design.