An Intermediate Google SketchUp Tutorial - Part 2.pdf - Sketchup - ania991

An Intermediate Google SketchUp Tutorial - Part 2

Note: Before reading this tutorial see Notice in the last paragraph.

In this

tutorial I am going to show you how to draw the quarter round and bull nose trim that make up

the bonnet of the Shaker Style Chain Driven Wall Clock posted on my Free Plans page. The front

view dimensions and trim detail dimensions are shown in the picture at left. Click to enlarge the

picture and study the dimensions.

The circle center highlighted with an arrow in the picture is an important reference point. It is the

same circle center used in Part 1. If you recall it was 7/64Ǝ above the bottom front edge of the

stock. In this drawing it lies on the front most plane; that is the same plane as the 1/4Ǝ flat surface

of the quarter round trim. This will be obvious soon.

Notice that the circle radii are 1/32Ǝ greater than either a whole inch or inch and a half. This is to

allow a 1/32Ǝ gap (clearance) between the top of the door¶s arch and the bonnet. The bonnet trim

is made of two pieces: a quarter round trim made from 1Ǝ by 1 1/4Ǝ stock and bull nose trim 1/4Ǝ

thick by 5/8Ǝ wide.

The picture at right shows the side view of the bonnet trim. Note it extends from the front most

face back 9 3/8Ǝ.

There is symmetry to this bonnet on either side of the vertical center line, and I am going to

make use of that symmetry to reduce the amount of work I need to do to create these

components. I am going to start by making the side quarter round. The star of this show is the

Follow Me tool. First, using the Line and Circle tools I make an outline of the quarter round and

a path to follow with the Follow Me tool. See picture at left. I used the Rectangle tool to make a

1 1/4Ǝ square in the Red/Blue plane and then used the Move/Copy tool to move the bottom line

up 1/4Ǝ. This leaves room for the bull nose trim later on. Starting at the corner of the rectangle

closest to the origin I draw a 3/4Ǝ radius circle.

One point I made in Part 1 and want to stress here is that when using the Circle tool always strive

to have the second point (the none center point) reside on an edge, preferably one that aligns with

an axis. It is especially true in the modeling of trim like this where curves constructed with

circles will end up coming together. This technique does not always produce a perfect seam, as

we will see shortly, but it does create a much better seam than a non-perfect circle otherwise

would (remember these are circles made of polygons).

After some erasing using the Eraser tool I get the picture at right which shows a partially

completed quarter round using the Follow Me tool. I complete this part by extending it to the end

of the 9 3/8Ǝ path. Then, selecting all primitives by clicking three times on the quarter round, I

create a group (no need to create a component at this point, although I could if I wished).

The side quarter round and the front quarter round will meet in a miter joint of 45 degrees. So

now I will create a slicing plane. Enlarge the picture at left and study it. Starting at Point 2, the

corner, I create a 45 degree construction line across the top. Now, starting at Point 1, the

intersection of the construction line and the edge, I draw a line to Point 2, continue the line to the

Origin, continue on to Point 3 which is located with the help of the inference engine, and end

back at Point 1. I have created a rectangular plane with one edge on the Blue axis and 45 degrees

to the Blue/Red plane. The slicing plane encompasses and slices through the quarter round.

An Intermediate Google SketchUp Tutorial - Part 2.pdf