Three Touching Circles

[Rik]

Thank you Rik for both comments.

I am hopeful there is an fantastical solution that someone knows of that I can smack my head when we find out.

Acorn

Actually, I've had situations where I've had 2 objects side by side, and the 3rd just doesn't want to snap below them in the centre.
This exercise has obviously shown why that doesn't happen?!

[Acorn]

Acorn, your solution and mine are very similar. You basically used snap where I used nudge ... I generally don't trust the magnetic snaps - although to be fair, they are better than they were.

Keith, I have never had problems with Snap to Objects. I may sometimes lock other items or go Solo. If Snap to Grid is on, I can see where the snap point can jump around.

Nudging is fine but if I change the diameter to 201px, you have to change the Nudge so it is more fussy.

Acorn

[Acorn]

Actually, I've had situations where I've had 2 objects side by side, and the 3rd just doesn't want to snap below them in the centre.
This exercise has obviously shown why that doesn't happen?!

Rik, that is the precise nub of the Challenge.

If you select "Show object edit handles", you will see a circle only has one selection point and you would have to rotate this around to the required angle to make a Snap work properly.

It is also an exercise in lateral thinking where you change the problem to a solution you know works already.

Thank you all for your contributions and interest.

Acorn

[Acorn]

Last part of the Challenge.

How can you use Xara to prove your solution is exactly touching and not have a small gap or overlap somewhere?

Acorn

[Acorn]

Last part of the Challenge.
How can you use Xara to prove your solution is exactly touching and not have a small gap or overlap somewhere?
Acorn

Well, if you have a circle diameter of 200px then two horizontal and adjacent touching ones must be 400px across. This is using Xara as a straight ruler.
If you rotate all three circles 120° and measure again you get a width of 400px. Do the same once more and if the third measure is 400px, the circle all touch with no gap or overlap.

Xara has a little noticed pair of measurements you get for free: Perimeter (P) and Area (A).
If you select all three circles of 200px diameter, Xara reports a combined perimeter of 1884.8px and an area of 94,200sqpx (px²). [Xara thinks pi is 3.14 - @Dear Xara, use 355/113 instead - I know, you are probably counting whole sqpx]
Here is the trick. Select and clone all three circles then Add Shapes. Then check the P & A. If there is no overlap then both values are identical.
Try it with moving one circle in 1px H & 1 px V so if overlaps.
The combined P is now 1747.1px and the A is 94,100sqpx.

My best trick is to switch to Outline view. Even a small overlap shows a break in the outline.

Acorn