How can I control the dots (and gaps) on a stroke in Illustrator?

Question

I'm trying to recreate the attached image, and I'm hitting a wall that seems like a no brainer, but I just can't figure it out!

I need to have a dotted line with a set number of dots (29 to be exact) that vary in size (largest to smallest) and that spaces out evenly. I know how to control the number, I know that I can use the width tool, or a width profile to control the sizes, but every time I do all the correct steps, I can't get them to space out, the dots just kind of stack up on each other.

Help? Thoughts?

Answer 1

Oh man I got this.

1. enable auto-guides (CTRL U) to make your life easy
2. draw the smallest size circle you want
3. duplicate it straight off to one side (eg click and hold the circle, then hold ALT SHIFT and drag off to the right).
4. increase the size of the new circle to be the largest one
5. select the blend tool (W) and click on a point on the first circle, then the corresponding point on the larger circle. Now you have a smear of circles.
6. press ENTER to open the blend menu and select "Specified Steps", setting it to 13.
7. duplicate this (ALT while dragging) to save your work!
8. select your new copy and go to Object → expand to destructively remove the blend effect.
9. ungroup your circles (CTRL SHIFT G) and select the whole row. now under the alignment panel, select the equal distance option. adjust the distance of one side as you need to and re-space them until they look nice.

10. note that at this time, if you want to adjust the scaling you just go back to your earlier copy! Moving on...
11. select all but the largest circle and press R for rotate, hold ALT and drag the rotation center to the center of the big circle, and release. enter 180 degrees and hit the copy box, then click OK
12. draw a line starting at the center of the big circle to just beyond the margins of the distant circles (about a quarter of the distance between them). make sure this line has no fill or stroke. Don't forget to duplicate the steps along the way so you can go back!
13. select the circles and invisible line and go to the brush pallet and click the "new page" icon.
14. set your art brush to scale proportionately and then click OK.
15. draw a circle, remove the fill, apply the stroke! go back and adjust a step if your circles look bad.
16. Once you have your rings of circles arranged, you can expand their appearance (under Object) and apply colors. Voila!

NB this will warp the circles so they are no longer perfect. If you look really close, you can see that they're a bit smushed. If you want perfect circles, you can Average each blob into its center point (or draw radii out from the ring center bisecting each circle) then move a fresh circle to the intersection by hand. Tedious, but it'll do. For even more perfection, do the math to figure out how to space the arcseconds evenly...

I found a slightly more complicated way to do this without squishing the circles:

1. make 3 horizontal lines with a thin stroke, evenly spaced apart. The width should be the diameter of the smallest circles.
2. scale the middle line to be the diameter of the largest circle
3. select all three lines and create a new blend (Object → blend → make). As above, set the steps to 13. NB: sometimes there's a "twist" in the ribbon we're making. If that happens, just rotate the middle line 180 degrees to untwist the blending ribbon.
4. space them evenly just as above
5. bonus step: make 2 strokeless lines 1/2 the length of the gap between the other lines. add one to each of the smallest lines.
6. drag this whole thing into a new artbrush.
7. draw your circle and apply the artbrush. Expand it to make a bunch of evenly spaced arcs forming a circle.
8. NEW STEP Object → path → simplify. Set the angle to 180 degrees and check "straight lines"
9. now that you have a lot of straight lines, draw a circle of any size anywhere. Color it as you want.
10. drag this new circle into a new artbrush, this time setting it to scale to fit the whole stroke
11. apply this circle brush to your lines. delete the spacing nubbins at the end (they are the tiny circles touching at one side of the circle) Done!