SketchUp Components and Groups

An Eccentric Anomaly: Ed Davies's Blog

Just over a year ago I posted Components and Layers in Google SketchUp. This is something of an update to that.

Components vs Groups

However, his description of his default choice of groups over components towards the end of the video is contrary to my experience. Presumably because of the problem he describes with changing one instance of a component and unknowingly changing others elsewhere in the drawing SketchUp shows how many instances of the selected component there are in the model:

Therefore, it's really not difficult to keep track of where components share their structure.

Usually, if you edit one instance of a component you want all of the other similar components to change as well. When you don't it's very easy to select the one (or more) instance(s) you want to change, right click and choose Make Unique to make it (or them) into a separate distinct component. SketchUp adds '#1' or whatever to the end of the component name to avoid confusion but usually you want to rename it (and maybe the original as well) to something a bit more descriptive.

Fundamentally, if you leave things as components you can easily split them off from their original later whereas if they're distinct groups there is, as far as I know, no quick and easy way to merge them back together again. If you just use components, not groups, then:

  • When you want to make unlinked copies you need to remember to use Make Unique and
  • Once you've done that you need to give the new component a more sensible name than the temporary one generated by SketchUp.

Make Unique is quick and easy. You'd probably want to give your groups sensible names anyway.

Components for Easier Editing

While we're on the subject, it might be worth mentioning a component trick which it took me a while to make into a habit.

If you want to edit a component which is mixed into the drawing in rather intricate ways it can sometimes be awkward to see what you're doing. An easy trick is to move the parts you want to work on a fixed distance (say 10 metres) along a suitable axis, work on them there then move them back the same distance.

An extension to this is to simply copy a component out in the same way; edit the copy and the original will “magically” update to match with no need to copy back. Sometimes adding a few construction lines from relevant points on nearby components and copying them as well makes this easier. Once the copy has been edited, it and any associated construction lines can just be deleted.