How do you find an axis for rotating something that's round?
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E.g., suppose you have a circle in the XY plane. You pull it up along the Z axis, so now it becomes an upright cylinder (looks like a smokestack). But you want to rotate it so it's horizontal, parallel to the X axis, so it looks like a tunnel. Invoking the rotate tool, you try to stick the protractor to the X or Z axis of the cylinder, but you can't find either one on the round surface. What do you do? Thanks.
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The rotation 'protractor' changes color when its locked ontp the XYZ axes [RGB].
If you hold the shift-key down it locks the protractor onto that setting until you snap it onto something.
To get the protractor to set to a particular axis change your view so that you see the ground [blue=Z] (on 'plan view) or more 'sky' [red=X or green=Y depending on view direction] - either in 3D or one of the four 'elevation' views. Lock it to what you want if needed, and then snap and rotate as required. If you hold the protractor over a face it'll get set to the face's normal [either black if that's non-axial or an axis color if it's orthogonal]. To set the protractor to be oriented square to an edge drag along that edge and the protractor will lock square to it - centered on the edge... you can draw temporary lines to achieve this too
Note that you can also draw circles snapped onto any face, or in your case axial 'in space' by using the same 'trick' of seeing more 'ground' (e.g. plan) or 'sky' (e.g. elevation) and getting the circle's color set to say red or green and shift-locking it to that - then you don't need to rotate the cylinder at all, as you will have made it in the correct orientation to suit, and just move it to suit.
Also remember that group stuff as you go separates geometry and allows you to move/rotate things around without messing up adjoining things -
Sometimes I make a temporary cube to set the rotate axis I want so I don't have to change my view.
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@davidboulder said:
Sometimes I make a temporary cube to set the rotate axis I want so I don't have to change my view.
Good tip.
But if you set scene-tabs swapping views is pretty painless............
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Hi folks.
Don't forget that the rotation protractor can be set parallel to a plane by using any of the standard plane of SU, depending on the orbiting of the view or using any convenient surface. Once oriented, you can lock it by pressing and holding down the SHIFT key. Then you click to establish the "Center of rotation". The axis of rotation will, of course be perpendicular to the plane of rotation and the center of rotation will be on the point where you click.
BUT, there is also another less known way of using it, that is described in the help with the title "Folding along an axis of rotation"
It can be read on this page:
http://sketchup.google.com/support/bin/answer.py?hl=en&answer=116434
Basically, it can be resumed as this:
1 - Press AND hold down the Left Mouse Button (LMB).
2 - While still holding the LMB down, slide the cursor along any axis, line, edge, whatever you want to establish the "Axis of rotation" instead of the Center of rotation". If you want to use any of the standard axes, simply try to slide the cursor in a path that is about parallel with the axes. When you get the color of that axis, release the LMB to set the center and the axis of rotation.
When done with this positioning of the axis of rotation, proceed as usual with the rotation.
With this variation on the Rotate Tool, you can rotate any shape around any axis.
You can also use this method to rotate a Guide (or construction line) with the Protractor Tool , not to be confused with the Rotate Tool..
Just ideas.
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[flash=628,360:1k0badql]http://www.youtube.com/v/sf0LprZpe1A[/flash:1k0badql]
Consider taking a great advantage of those two excellent (and highly recommended) tools:
CenterPoint v.1.200 by Todd Burch
&
Construction Line Tool v1.0 by Jim*s
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