Creating a custom grid for a logo in Illustrator

Question

I always wondered how to create a those custom grids like you can see on David Pache's works (http://dribbble.com/helveticbrands) and Igor Duibanov.

I found out how to create a tangent to a circle from a certain point but I can't find how to draw a tangent that will cross through 2 circles like here:

I'm really in love with this topic but I can't understand how to work like this, I tried but I failed and didn't come even close.

Answer 1

What you're referring to aren't really grids; they're construction guides. The grid is just what's formed by the horizontal and vertical components.

And while some of these construction guides look really fancy and complex, they probably weren't as hard to create as you imagine. Usually, the designer starts with a general idea of what they want to build and then gradually lays down guides over a long design process. So they might end up with a very complex set of guides at the end, but they probably started with just a few horizontal and vertical lines or maybe just a single circle.

But on to the part that you probably don't want to hear...

So, remember those days way back in high school, sitting in your geometry class, listening to your math teacher drone on and on about axioms and postulates and theorems, and you muttered to yourself "when am I ever gonna use any of this stuff?" Well... this is one of those times.

That's actually why a lot of the construction guides you see are so complex—the designer needed to use geometry to find the precise positioning of one element based on another element, and they required a lot of intermediary guides to get there.

That isn't to say all of these designers aced their geometry classes. Many of them probably don't even understand the geometric theorems they're applying, and they're simply applying tricks they've picked up through trial & error aided by perhaps a little logical intuition. And this is something that most anyone can do. It just takes a little practice.

Answer 2

Here's a quick and dirty method for drawing outer tangents for 2 circles:

1. Start with your 2 circles. Orientation and size don't matter, as long as 1 circle is not wholly surrounded by the other.
   

2. Draw a rectangle with width (or length) equal to the diameter of the smaller circle. It's length (or width) should be at least as long as the distance between the 2 centers. The end of the rectangle should be centered on the smaller circle's center.
   

3. Use your Rotate tool and set the rotational reference point at the center of the smaller circle, then drag an edge of the rectangle until it forms a tangent on the larger circle.
   

4. Clean up your rectangle length, and duplicate your efforts on the other side.
   

The result may not be mathematically perfect, but it can be as good as you desire.

Answer 3

I haven't used AI in a long while, so not sure if these are features that now exist, but back in the day, there weren't tools for doing geometric connections such as tangent lines and the like. CAD software, on the other hand, is designed specifically for that, so is often where you'd go. To do it in AI, it's a lot of zooming and eyeballing.

Keep in mind that a lot of these design grids you see on places like Dribble are added AFTER the fact. They're kind of neat as a presentation tool, but odds are they aren't used as often for the actual creation of the design as much as you think.

Answer 4

A simpler and more precise way is to use Hiroyuki Sato's 'Common Tangent' script for illustrator

1. Create and select the circles you wish to combine
2. command+f12 to open illustrator script, open 'Common Tangents.js'
3. The common tangents will be drawn for you, you can close the lines off with the pen tool to create solid shapes from the lines
4. use path finder to merge all the shapes into one object

It is included in his excellent suite of scripts: http://park12.wakwak.com/~shp/lc/et/en_aics_script.html