How to Select and Move a Rectangle by its centre


#1

Hi… I suspect this is a really stupid and obvious question, but I have been playing and reading for the last hour and can’t work it out.

I need put a rectangle of specific size EXACTLY in the centre of another larger rectangle.

I have created the first larger rectangle and setup guidelines so the centre is marked and have then drawn the 2nd smaller rectangle which I need to move right on the centre point of the first larger rectangle.

If I ‘move’ the smaller rectangle, the cursor “locks” to the center of the bigger one as I get close… But this is the point where I selected the rectangle, and not the center.

So it seems I just need to select the smaller rectangle at its center when I move…

I read that I can find the centre by hovering at the outside edge of the smaller rectangle until it shows “midpoiint” and then doing the same on the adjacent side and this shows me the center. BUT when I click this “centre” point I get an error saying “Nothing Selected. Use select tool for multiple items, or pick one item to move”

It seems that I can move the smaller rectangle by clicking at ANY part of it… But as soon as the midpoint is shown and my cursor snaps to this line, I get the error.

I even tried to draw to lines on the smaller rectangle with an intersection at the centre… But when I try to select it now to move, the lines move and not the rectangle.

What am I missing here?

All I want to do is pick up the smaller rectangle and put it directly in the middle of bigger one… I know I could do this by trial and error using the measure tool to get it central… But I want to do it perfectly every single time.

Thanks in advance for any help you can give.

Jon


#2

I think I just worked it out… I need to select the whole object first… So a triple click turns the whole thing blue and then I can now move it at the center point.

Sorry for wasting your time.


#3

Helle
I think you must try offset tool. You type the distance from thé edges of thé big rectangle you want to place thé small one.


#4

Thank you for reporting back.


#5

Did you make groups for each rectangle ?


#6

Tried the offset too and it would be ideal… But as far as i know you cant specify the size of the smaller rectangle, so you have to work out how far you need to come in from the edge.

So say for example th first rectangle was 100x100 and i needed a 80x70 rectangle ontop, i could use the offset tool and come in 20mm on one edge and 30mm on the other.

But when you get into very specific measurments, its not so easy…

Is there a way to use the offset tool, but specify a size for the new rectangle (rather than a distance from the edge)?


#7

Ok I think I understand make your small rectangle far from the big one typing 80;70 make a group then use the type measure tool, click to create the diagonals construction lines of both rectangles, then with move tool pick the center of small one and place it at the center of the big one…


#8

Often it is faster to use two movements with the centers of two edges and fixed inferences …


#9

Thanks Cotty… Thats a great tip… Will try that for sure…

As for the “group” suggestion, i am not sure i understand what you are saying as i havmt touched groups yet… But will have a play and see what i can work out.

Thanks all…

Jon


#10

Groups are one of the keys of Sketchup it consists in enclosing edges and faces to make an object that doesn’t stick the rest of the model.
Select with 3 clicks the connected elements (edges and faces) you want to group then right click “make a group”.
Save time and check those videos :
http://www.sketchup.com/fr/learn/videos/58
For groups see part 4
And remember as said the Sage: Group Early, Group Often !


#11

I often use a Ruby, Add Centerpoint. It comes handy in situations like this.

Rubys are a bit advanced for a beginner, it’s best to get the basics down before you extend the program. When you are ready to move on, check out a Ruby tutorial. Meantime, Cotty’s technique is great.