Sketchup Modeling for 3d Printing

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Revision as of 12:13, 22 March 2012 by Buback (talk | contribs) (work in progress)
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Google Sketchup is a great program for someone just getting started with 3d modeling, but there are some common mistakes that you'll need to avoid in order to design properly for 3d printing. Here are some tips and tools in order to get you started right.

Extensions

You will certainly need a way to export your file in a useful format, which for us is the .stl format. Sketchup doesn't support .stl out of the box, so we need a plugin, which you can get here.

another plugin that is essential is the Cleanup plugin. get that here.


Good tips for better modeling

click once selects face or edge, double click selects all adjacent edges/faces, triple click selects all conected faces/edges (i.e. the whole moddle under your mouse)

you can do a lot with just the mouse in sketchup, but it's always good to have one hand on the keyboard. Shift-clicking is what you'll be doing half of the time anyway, since it often modifies the tool or intent of your action. Ctrl-clicking and Alt-clicking also do a lot of useful things, so always read the tooltips at the bottom of the screen until you know these by heart. -Shift select is a +/- select, you you can select multiple objects/faces/edges. -Middle click orbits, shift+middle click pans -middle double click will move your view to where your mouse is. -'k' shows back faces -'spacebar' takes you out of a tool and back to the select tool -'m' picks the move tool -etc. most of the tool quick keys are under the left hand.


Bad form, and how to fix it

Reversed Faces

The most common mistake I see on thingivers models is reversed faces. If you are modeling with paints/textures, you can see the reversed faces by clicking on view>Face Style>Monochrome. the reversed faces are blue-grey. This becomes an issue with .stls creation because the surface normal points inward instead of outward, and will make the model non-manifold.

If you spot a reversed face, click on it to select it, then right click and select 'Reverse Faces'.

If there are a bunch, select a good face, right click and select 'Orient Faces'. This will align all faces to the same state as the selected face, usually. sometimes there are faces that don't want to work, so you'll have to select those faces and revers them manually with 'Reverse Faces'.

Groups and components

Groups and components are excellent ways of organizing your components. You can quickly create a group, copy it, an flip it in order to make a symmetrical part. When you do this, however, be aware that the components themselves have their own axes, which can mess up the stl bed position. you should always explode all your groups and components and place them by the origin before generating an stl.

Also be aware that there is usually an internal face you'll need to remove so that the stl will be clean.


There's a lot of info to cover, and then i'll need to format it all in a clean way, so stay tuned. --Buback 16:13, 22 March 2012 (UTC)