Why dont I need a grid..?


#1

Hi all, old dog in ancient 3D calling - new to SketchUp. Starting to use SU for redesign of our house.

I’d want to use exact measures for the project. I’ve learned how to input distances in the measurement field, but how do I put in an exact starting point?

Say I want to make a hole for a window in a wall. I want the window-hole to be exactly 1.2m from the ground, and be 0.6m wide and 1.2m tall. Using the rectangle-tool, I can enter the dimension of the rectangle - but I can’t figure out to exactly enter the starting point (the first corner).

I’ve downloaded a grid extension that helps me do this, but I have a feeling I’m missing a basic skill to achieve this without extensions.

Greetings from Denmark - Kim Bjoern


#2

For your example, use the Tape Measure tool to establish a corner for the window. Click and release on the bottom edge of the wall and move the cursor up. Type 1.2m to set a guideline at the right height. You also need to set a distance from a corner so repeat by clicking and releasing on the edge at the corner then dragging over. At the intersection of the two guidelines you’ll have a starting point to draw the rectangle. When you’ve finished with the guidelines, you can delete them with Edit>Delete guides.

Of course there are other ways to do it, too. None of which require a grid.

Work with the inferencing and the other tools available in SketchUp and I think you’ll see that grids aren’t needed. Besides, grids would be limiting in that they would drive the precision you can work to. And having grids in 3 different planes would make a very cluttered work space.


#3

Personally I draw a rectangle on the wall face; using the bottom corner of the wall (say it’s 0,0) for the first point and typing in 1500,1200 (assuming it’s 1500 in from the edge of the house). This gives me the bottom corner of the actual aperture I want to cut: I then click on this point as the start of another rectangle and type 600,1200. Then it’s a simple push/pull operation to make the opening and delete the extra two lines.
(Note I could use the line tool to place the initial corner guide rather than a rectangle, but I know I want to use the rectangle next so it saves me changing tools… I should probably use the [l] and [r] shortcut keys and would only have one line to delete rather than two.)

For the next window I select the opening I’ve just made and copy it across - doesn’t matter what size the next window is, as long as I get the distance between openings correct. I then use the push/pull to re-size the opening for this window.

Alternatively I use the push/pull with [ctrl] and push the edge of the window across to form the outside of the next window and will have to delete the top/bottom faces generated.

In both these cases I use “proper” lines as guides rather than the guidelines generated from the measurement tool: I find that “guidelines” are rarely of use because of the great inference system that is already built in - only if the inference is off-screen or I need to snap multiple times do I ever use it. (Even then, a true line works just as well.)


#4

Many thanks for the replies. Haven’t tried yet; but I understand both suggested approaches. Great!

Best - Kim Bjoern