Step 9: Tilt Axis
Cut a wooden disc to fit the arm of the Hitec HS805BB servo. Secure it with the provided screws and screw it to the servo. Cut all the pieces from the 9 mm plywood that are shown in the second step. Be sure to round the top edges of one side, as shown in the last picture. If you don’t, your ammo belt might get stuck. Place the two ball bearings into the two identical side pieces and paint them after filling and priming. Cut a hole into the third piece to fit the servo. It’s very important that the axis is perfectly centered. You should really spend some time on this step, since it will greatly affect how well your gun will work.
Place the wooden pole holding the Nerf Vulcan between the two pieces with the bearings. Now use the 128 mm rectangular block of wood as a spacer (the lower end of the plates has to face the back of the gun). At first I tried to secure the spacer with glue, but the connection was just not strong enough. So I used M4 x 40mm wood screws, to secure it in place. It also makes it easier to take the gun apart later should it be necessary.
Glue the 45 mm rectangular block of wood to the bottom of one of the panels and cut the wooden pole to the correct length in order for it to perfectly fit into the wooden disc which you've build before. Attach the servo and screw the wooden disc to the pole, as well as the servo plate to the spacer.
Then use the brackets, screws and wing nuts to attach the base, as shown in the pictures. Using the wing nuts allows an easy disassembly of the gun and therefore assures easy transportation.
Use the lead pearls or something similar as a counter weight, until the gun is perfectly in balance. Hot glue works great to hold the pearls in place.