Shaker and Ladder Back Chairs are frequently fitted with curved or bent back slats. A reader asked how to model these compound-shaped components in SketchUp. Below I've shown my method in six steps.
Assume this is the Back Slat design we want to create in SketchUp:
Step 1: Create the flat rectangular plane for laying out the arc shape shown in the above top view. When using the Arc Tool, I prepare a flat plane for layout. I do not try to work the Arc Tool in empty space (always on a surface). My plane is on the Red/Green Axes, so the view below is from the top.
Step 2: Use Push/Pull Tool to pull up the full height of the back slat
Step 3: Now we need to cut a scroll shape in the top edge of the back slat. Create another flat plane in front of the Back Slat (as if a projection of the curved surface). My plane is on the Red/Blue axes. Then create the arc curves on the surface of the plane. I typically draw a straight sloped line to help with the layout of the connected reverse arcs, using the endpoints and midpoint of the sloped line.
Step 4: Push/Pull the arc shape through the back slat. Depress the CTRL Key when using the Push/Pull Tool in this case.
Step 5: Select all, then execute "Intersect Selected", and clean up waste
Step 6: Copy the left half, moving over to the right. Then "Flip along Red Axis", and connect the two halves of the back slat.
In general, when facing components with compound shapes, the "Intersect" feature will probably be required.
Tim
http://killenwood.com
