Free Flight "Indoor" Planes Great Performance - Fun Flying Model Airplanes
Sharkies Machine - Build
The Sharkies Machine is the first airplane that I made by putting into practice all that I had learned in model airplane design. It became a successful design and warranted publishing. Here are some of the pictures that make up building a Sharkies Machine. Now is a good time to Download a PDF of the Sharkies Machine plan.
This is a framed up Sharkies and is what you will have after completing the stages of construction. It's not a first time build for the beginner, primarily because of the elliptical wing, stab and rudder. Each of these parts is made up from a laminating technique.
A good picture of the completed sections, Fuselage, Stab, Fin and Wing are the major components in this airplane. I will start with the fuselage, then the wing and tail section and other mechanical parts that go into this plane.
The fuselage is built in sides in the usual fashion over the plan and perhaps on top of some wax paper to keep things from sticking to the plans. It's pinned in place and built from the outside in laying the longerons down first and then building in vertical structure from there. Sections that are a bit tricky are the nose and canopy section and perhaps the tail cone section but things should progress normally.
Here is a picture of a method to bring the nose section together with a jig in order to make things square and solid with the right alignment.
The same trick is employed at the tail section using a number of V jigs pinned to the plan so that the tail section shall come together properly. In this picture is another Square Jig you can see inserted over the fuselage to make for square alignment.
The wings are made around an elliptical form made from cardboard. This form is pinned to the plan and the laminations of 1/32 strip are are soaked in water and then wrapped, wet, around the form using white glue as a bonding agent. This may look tricky but you will get the hang of it. Let this piece dry completely before finishing the rest of the Wing. I let this dry over night.
After the wing is formed the ribs are cut individually and installed in the traditional fashion. The spar is added and then the centre section sheeting is added on the top only.
In the sections where dihedral breaks occur, you can include some triangle gussets to give the joints some strength.
The Stabilizer is made the same as the wing and so is the rudder, add the internal structure in the normal fashion. (See the inset picture)
Wheels are made by turning a piece of balsa on a mandrel on the Dremel Tool and then sliced off in the right size. I make all sorts of balsa wheels this way and they come out great.
Here is a picture of the assembly of wheel pants and you can see the balsa wheels that were made in the last step.
In this picture, the stab and fin are added to the tail section of the airplane. I glue the trailing edge of the stab in and adjust the front portion of the stab when I trim the airplane out. Here you can make out the balsa shim in the stab section. This picture is inverted with the fin downward. You can also see the aluminium rubber motor peg in through the fuselage.
On top of the fuselage is a wing mounting wire, cabin section and landing gear exit location.
The front end on this airplane is involved but make up a good light spinner to add some style to your airplane. The pictures that follow are a method for making a Sharkies spinner and prop section.
Here is the first version for the prop hub, nose block and spinner mounted on the propeller. This spinner is permanent.
Another picture of the spinner from another angle.
Like the wheels we start with a piece of plywood mounted on a mandrel that we are going to spin in the Dremel Tool.
Mounted on the mandrel is a block of balsa with the grain going length wise.
Attached to the Dremel chuck and ready for forming. Go slow speeds at first.
Partially shaped spinner.
Shaped spinner ready for the next step.
Now insert a brass tube in the hole of the prop hub. To do this you may have to drill out the prop hub to accept the 1/16th brass tube. The brass tube that you insert has to be long and able to support the spinner.
The spinner is removed from the mandrel and split apart through it's middle and then carved inside to accept the plastic prop and brass tube. Since this is a small spinner, there is no need for a large amount of hollowing.
Re-assemble the halves of the spinner over the prop and brass tube and glue them together.
Here is another picture of the spinner.
Added to the spinner are the prop drive wire and a balsa back plate on the hub to improve the shapes.
Notch the front of the spinner to accept the drive wire and its bend.
Completed spinner and balsa front end of the airplane. The Propeller drive wire becomes the drive point in the front of the spinner.
I have found this method to be successful in getting good solid spinners that stay on even if your model hits something. They are light and robust and last the lifetime of the airplane. At first they take a bit of work to build but in the end are worth the effort in looks.
Here is a final picture of the first Sharkies Machine.