3D Stars #3: Making 3-D Stars

After creating a program to calculate dimensions and cutting angles and designing and building a jig to make the cuts with, I was ready to put things into practice.

My first trial was with some old (30+years) cedar fence pickets. I wanted an old “barnwood” 3-D star. I quickly decided that even though the wood was cheap (free), it varied greatly in thickness, even within one piece, and it was extremely brittle and splintered easily when cut. Needless to say, I wasn’t pleased with the finished pieces.

My next attempt was with new 1×4 rough cedar that I already had on hand (slightly thinner cedar fence pickets would work equally well). This material worked much better. I made several different cuts and kept changing my cutting jig around trying to get the pieces like I wanted. After a lot of trial and error I finally came up with a set of simple and easy cuts to simplify the process that I’ll cover in a moment.

First, however, I made the pieces for a 3-D star that had a “Long Arm” = 9 inches, a “Short Arm” = 3.44 inches, and a center “Height” = 1.5 inches. I cut the bevels for all 3 sides just like my program calls for and the resulting star layed flat on the table.

While the star is very pretty, it’s also very thin on the outside edges and at the star points which makes it very fragile. Additionally, trying to cut the very steep undercut bevel on the outside edge (61.7 degrees in this case) removes a lot of material and must be done in at least 2 passes to keep the edge smooth and on angle.

I decided to try a little different approach to see how I liked it and was quite pleased with the outcome. I decided to NOT bevel the outside edge, but to leave it uncut. Since it is at a 90 degree angle with the top surface, when the piece is elevated to its 3-D position, this edge naturally angles back under the star. Now the star is much thicker, sturdier, and much easier to make.

This picture is of both stars, with the thicker star on the left.

This is the same setup but at an angle to highlight the difference in the stars.

Here’s a closeup of the outside edges.

The following picture shows the progression of cuts needed to make the second star.

On a Radial Arm Saw (RAS) make the star as follows:

1. Cut a length of stock that is wide enough to make one piece and 1/2” to 1” longer than the “Long Arm” length. Cut a set (5 point star = 5 pieces, but cut at least 1 or 2 extra for spares).

2. With the GOOD SIDE UP, cut the “Long Arm” bevel on the outside edge of the work piece. Rotate it 180 degrees and cut the same bevel on the other outside edge. Repeat for all pieces.

3. Set the jig in the 5 o’clock position with the angle between the saw blade and the jig hold down at the “Point Angle”. Put the saw blade straight up and down.

3a. – Put a piece in the jig with the GOOD SIDE UP. Slide it up and down the jig hold down until the saw blade will contact the outside edge about 1/4” down from the upper edge of the work piece. Clamp it and cut. When the piece is cut, it will yield 2 RIGHT HALF star point blanks. Do this for half of the work piece blanks that you have.

3b. Put a piece in the jig with the GOOD SIDE DOWN. Slide it up and down the jig hold down until the saw blade will contact the BOTTOM outside edge about 1/4” down from the upper edge of the work piece. Clamp it and cut. When the piece is cut, it will yield 2 LEFT HALF star point blanks. Do this for the other half of the work piece blanks that you have.

4a. Adjust the jig to the 7 o’clock position with the angle between the saw blade and the jig hold down at the “Interior Angle”. Adjust the saw blade to the “Short Arm Bevel Angle”. Using a RIGHT HALF star point blank, place it GOOD SIDE DOWN with the “Long Arm” edge against the guide. Slide it up and down the jig hold down until the blade will cut the “Long Arm” the correct “Long Arm” length. Clamp it and cut. Repeat this for all of the RIGHT HALF blanks.

4. Adjust the jig to the 5 o’clock position with the angle between the saw blade and the jig hold down at the “Interior Angle”. Adjust the saw blade to the “Short Arm Bevel Angle”. Using a LEFT HALF star point blank, place it GOOD SIDE DOWN with the “Long Arm” edge against the guide. Slide it up and down the jig hold down until the blade will cut the “Long Arm” the correct “Long Arm” length. Clamp it and cut. Repeat this for all of the LEFT HALF blanks.

5. Double check all of the pieces for consistency from piece to piece and make any corrections needed before proceeding.

6. Glue up enough right and left half sets for a finished star. Allow them to dry before proceeding.

7. Dry fit the pieces together and make sure that all of the gaps between the segments will close up properly. They probably won’t, so now is the time to hand/power sand some of the edges so everything will fit together. Glue up and enjoy!!!