The control panel hosts the player controls and the controller interface board. It detaches from the main carcass to allow the cabinet to pass through doorways.
The entire panel is covered with a 1/8 sheet of Plexiglas, which provides the actual playing surface the players hands rest on. The control panel's art is sandwiched between the MDF top and the Plexiglas playing surface. This keeps the art save and clean.
The controller design used in this build is not easy to build. The corners require precise compound angles and relief cuts. The design can be drastically simplify the design by foregoing the 45 degree corners. Simple square corners are much easier to build. This change makes the controller a box with a slanted top.
The sides of the box are connected to the top. This is necessary to create a sturdy unit. During play user tend to be very rough. All the stress the unit is subjected to comes from the player's movements at the top of the panel.
The top is crewed into a bottom plate, which in turn is attached to the cabinet. The bottom plate must be removable to allow access to the panel's wiring. The whole control panel must also be removable to allow the cabinet to fit through doors.
Bolts with nuts connect the bottom plate. Bolts driven into threaded inserts installed in the top hold the control panel together.
Cut the bottom plate first and place it in your assembly area. Next cut the vertical pieces one at a time. Place each one in it's place on the bottom plate. Carefully measure, and move on to the next piece. Cut the top plate last. Attach the vertical pieces to each other with glue and brads. Clamp the assembly to the bottom plate, which acts as a form and keeps everything aligned. Make sure not to accidentally glue the pieces to the bottom.
Before attaching the top, prepare the Plexiglas. Rough cut it to the approximate dimensions of the top. Flush cut it using a router with a flush cutting bit.
Slagcoin.com has one of the best description of how to do the button layout. It's a great read. The Capcom 8 button layout is the most versatile layout for general gaming. If you do not have a design in mind, the Capcom layout is a good default choice.
The holes for the controls need to be driller with two different bits. A hole saw for the Plexiglas, and a Forstner bit for the MDF.
Clamp the Plexiglas to the MDF. This will keep the two pieces from moving. Locate and drill your holes through the Plexiglas using the hole saw. Go deep enough to score the outline of the holes into the MDF. Once all holes are drilled, remove the Plexiglas, change to the forstner bit, and finish drilling the holes the MDF.
Each joystick rests in a recess/cutout. The shape and depth of this recess differs from joystick to joystick. Consult the mounting instructions of your joystick for the correct shape.
Cut the recess with a template and a router. If your top is made from MDF, reinforcing the bottom with a strip of wood or metal will increase longevity of the top. MDF can be too soft for extremely lively play.
Join the Top to the Sides
Connect the top to the vertical pieces with glue and nails. After the glue dries, reinforce the corners. Temporarily clamp the bottom to the top.
Drill holes through the bottom into the thick areas of the top. These holes will accept the screws that attach the bottom to the top. Install threaded inserts in the holes in the top. Test fit the assembly.
The control panel is easily as much, if not more work that the entire carcass. Take your time. The user will interact with the control panel when he is playing. It's worth getting just right.