After a long absence, JLRockets is pleased to introduce . . . . the centering rings! We have three freshly cut rings made of ½ inch Baltic birch. The top two are 18 inches in diameter, and the bottom started as 18 inches in diameter before the sides were cut to accommodate indents in the bottom of the bottle. All three have a 7.5 inch hole for the stuffer tube. Jackson and Augie cut the rings with the help of Augie’s father Frank. I forgot to bring the camera to Frank’s shop, so you’ll have to make do with photos of the finished product. After a great deal of measuring and re-measuring, the boys rough cut the rings with a jig saw. Then they trimmed to size with a shaper. When we liked the fit, they used the jig saw to rough cut the 7.5 inch center hole in one of the rings. Then, they got the inner hole perfect using an oscillating spindle sander. That became the template for the other two. They used the template and a router to cut the center holes on the remaining two rings. They also cut the hole in the bottom of the bottle with a router. The best part is, they both still have all 10 fingers! Job well done boys. Although we have the basics for the core, we can’t start the attachment until we finalize the fin design. More on that later. Photos are: the core of the rocket beside the bottle; the finished centering rings; the motor hole in the bottom of the bottle; the bottom centring ring fitted into the indents; dry fit view from the top.