When you load your file on Tinkercad, there are no objects selected.
If you need to move or modify the object (or one of its parts), then you select it by clicking on it.
The selection identifies the category of the object: for example, if your file is made up of a group of objects, then you will select the group.
If you load single objects, then you’ll have a singular selection.
Clicking on the single object, you’ll open a tab in the upper corner.
This tab shows you some information about the selected object, for example:
-if it is locked;
-if it is correct;
-if the normals are right;
-if it is inside out;
The blue button means your model is normal.
The striped button means it is void, like a hole.
Let’s see better how it works:
I create a cylinder, and I put it on my solid object.
I select the cylinder, then I click on the striped button.
You’ll see how it changes from its normal color to a semitransparent one.
We created a hole in the 3D solid model. Now, if we export it, we’ll have a new file with the cylinder hole in it. (blue ring + cylinder hole)
Now let’s see the other two useful icons:
The locker icon blocks the object position.
The light bulb icon shows/hides the object.