How to exactly align shapes in order to unite them in Illustrator?

Question

I am new to Illustrator, I have been a Photoshop user for years.

Im trying to combine a rectangle and eclipse shape. The issue I am having is that the rectangle doesn't seem to line up properly with the ellipse. It's hard to explain so I have screenshots:

This is what I'm after (it is a lowercase b) with my issues highlighted in the Red and Green circles:

The issue in the Red circle is that I cannot get the edges of the two shapes to line up:

No. 1 shows X on: 591.5

No. 2 shows X on: 592.5

The main circle is 300x300, but seems to be on .0 x/y axis (eg. X: 692.0 - Y: 742.0).

The orange rectangle is 100x300, but is on a .5 x/y axis (eg.X: 591.5 - Y: 597.5).

I 'think' everything would be find if I could get the rectangle off the .5 axis? I have tried manually changing the number but it always changes back to .5 - Does anyone have any ideas how to get around this for the best result? I think if i could get the to line up perfectly I could then use scissor tool or something to snip anything hanging over?

My issue with the Green circle is not as big as the above issue, however, I am still finding it annoying. I basically put a 1/4 200x200 circle on top of a 100 wide square... I feel like the tranistion from straight line to curve isnt very smooth when scaled down to a smaller size (see 50% zoom in 1st link, green circle in 2nd link)... - Any tips here

Thanks in advance for your patience and help!

Answer 1

First, you might want to deactivate all snapping (also to pixel grids and all, see this question).

Then:

1. activate the Smart Guides (View > Smart Guides or Ctrl / Option+U);
2. select the move tool (V);
3. grab the rectangle shape by its lower left anchor (be sure the smart guide tip says 'anchor');
4. drag it over to the circle's bending point, where one of the circle's four anchors is, holding Ctrl / Option;
5. smart guides will point out where exactly the circle's anchor is, release your mouse button there while still holding Ctrl / Option.

That should do the trick.

For the second part of your question (yoour 'other' question): don't judge appearance of your final product by the pixels of a certain zoom percentage in Illustrator. It's only a preview, after all. If things look good when zoomed in, they will look good when printed or exported any other way. Heck, Illustrator preview has some other small rendering 'bugs' that never show up in final work.

Answer 2

Check if your strokes are aligned to the same place, ie inside, centre or outside - find this in the path and stroke panel.