I made this little string toy as my latest venture in 3D.  The principle is simple as you suspend the rocket from the planet you can pull on the rocket nozzle and make the rocket travel to the planet. I used a braided fishing line for my string.

Print spools and axle. I printed the axle by itself as it’s small. Once printed check the size of your holes and make sure your string fits. Assemble the axle and three spools. Cut two, 3 foot of lengths of string. Put one string on each spool. Make sure your knots are on the outside of the spool. One spool is large than the other. The larger spool should have the string wrapped around it with only about 6 inches left free. Make sure the flash on the HOUSING’s are clean where the axle will rotate freely. The housing has guides to fit the respective spools. Take a close look to put the loose string thru the hole in the end of the housing respective to the string guides. Once your Housing is assembled it should have a long string coming out one end and 6 inches coming out the other.  Insert long string thru Noscone. Orient Housing in to nosecone and glue. Put 6 inch string thru Rocket Body. Pull a little more string th make it 8 inches. Put the string thru the Nozzle. Tie a knot less than the 6 inches so it pulls tigh to the body when pulling on the long string. Attach Planet to end of other string. Enjoy.