Ranger Clone Build Part 11 Fin Line Prep

After looking online, I found a Rocksim file for the Ranger. This file only had a single 18mm engine so it was closer to a Big Bertha with an added payload section.
I added the two other engines to get the center of gravity position. With three C6-7 engines loaded, the C/G was about 5" from the rear of the main airframe tube.

The original Ranger kit had a 5" long X 1/8" diameter launch lug. Flying a three engine cluster with a 1/8" launch lug? Back in the 1960s all that was available were 1/8" diameter lugs. With the three engine cluster Estes went with the 5" longer lug.

I knew I wanted to go with a 3/16" rod and launch lug. A 2" long lug positioned at the center of gravity should be fine, and 3" shorter.

To mark the tube for a light roughing up of the surface, the center of the lug was marked and set on the 5" C/G mark.
Two tick marks were made just inside of the lug ends. I'll roughen the line up to the "short" marks.

After lightly roughing up the tubes, the pencil lines are sanded off.
Redraw the lines using your aluminum angle, extending from the upper ticks down to the end of the body tube.

You can double check your re-drawn lines again with the marking wrap.




Here's the launch lug position after lightly roughing up the surface. The positioning pencil line will have to be re-drawn.