Grumman F9F-2 Panther (oz12009)

About this Plan

Grumman Panther. Radio control scale model jet fighter, for IC ducted fan.

Scan from dfritzke, cleanup by Circlip.

Direct submission to Outerzone.

Update 14/03/2020: Added article, thanks to RFJ.

Quote: "Grumman F9F-2 Panther, by Marcus Norman. Ducted fan model for .40 size motpors and four function radio systems.

Fan unit: Although the fan unit, ie fan, stators, engine mounting-cum-wing tongue assembly, fan ring and rear wing are to be available commercially from Micro Mold, it may be that some modellers may wish to construct this part themselves. Consequently, I will describe this in some detail.

Engine mount and wing tongue: Commence the assembly of this unit by cutting out the engine mount-cum-wing tongue pattern from 1/4 in resin bonded ply-wood as per plan. (This particular mount is to take the K&B rear exhaust rear induction 6.5 engine with tuned pipe). It will be found that this mount will also take the HP rear induction and MAX 40 rear induction motors, but naturally the mount can be changed to suit any engine of the 40 class and all bolt holes drilled accordingly.

Carve and sand the streamlined section to shape as illustrated. Below the engine mounting holes glue 1/8in. strips of nylon or suitable hardwood totake self tapping mount-ing screws of size required ensuring that these are fixed firmly as they are not accessible when ducting is complete.

Fan ring: Cut a 5 in dia x 1/2 in plywood disc. It is upon this that the fan ring is made. Drill the centre to suit crankshaft of engine to be used (the importance of this will be seen later). Take a strip of 1/32 plywood x 2 in wide, bind this upon the disc and mark, to make a butt joint. Take a second strip of 32 ply x 2 in and bind this over the first piece of ply and again cut and mark for a butt joint. Now using either a whitewood PVA glue, epoxy or even a cyanoacrylate glue, form a laminated ring upon the 5 in disc taking care to get no glue between the disc and the ring. Allow to dry (see sketches).

Stator blade assembly: Cut a 2 in dia x 1/2 in ply disc. Cut out centre to allow propeller boss of the engine being used to pass through. Notch this front mount ring as per plan and round off front edges. Cut four 1/8 thick ply stator blades as per pattern on plan and sand and file to aerofoil section. (Note that the camber is opposite hand to that of the fan blades). Notch the back of the stator ring to locate onto the mount. Fit engine in mount and affix the stator ring.

Use white wood glue or epoxy of good quality (the fitting of the engine first ensures that the prop. boss passes through the stator ring centrally).

With the engine still in position fit the 5 in dia disc with the newly made fan ring still around it onto the crankshaft of the engine. Mark carefully the points on either side of the mark at which fan ring touches. Remove the ring and disc. Now cut slots into the engine mount at these marked points, to a depth as shown on the plan (side elevation of fuselage and accompanying sketches). Replace the disc and fan ring on the engine crank-shaft and glue ring in position in the slots. Allow to dry. (It is most important to keep the fan ring around the 5 in dia disc whilst this operation takes place as this ensures that the crankshaft of the engine is central in the fan ring, and thus the fan when fitted should run true within the ring). Remove 5 in disc from crankshaft of engine and remove engine. Replace the disc in the ring to hold it true whilst gluing stator blades in position. These are set equidistant around the fan ring with no angle on them. Glue with Araldite epoxy as this gives a very strong bond. When dry, remove the disc from the ring.

Rear tank mount ring: Cut from 1/2 in ply as per plan. Cut out top half to provide fuel line, pressure feed and filler pipe access to engine when tank cone is mounted later. Fix rear tank mount ring to engine mount as per plan. Take previously made 5 in dia. rear ring, cut a small slot either side of the engine mount at the trailing edge and glue ring centrally in position as per sketches. Form 1/4 x 1/16 in supports in hard balsa and fit between front fan ring and rear ring either side of engine mount top and bottom (see sketch). These provide support for the duct shells later in assembly. Make underfairing between front stator ring and rear tank mounting ring in 1/64 ply and glue in position. Sand complete 'unit' lightly to smooth finish; dope thoroughly and paint if desired. Do not paint exterior of fan and rear rings or balsa support pieces as ducting affixes to these items.

The fan: The most important item in the entire model, but not too difficult to make if the instructions are followed carefully. This particular fan design has been tried and tested in many of my most successful models. It is this design which will be available from Micro Mold.

The hub or centre boss: It is preferable to use a wood turning lathe or employ the services of a friendly joinery firm to turn up a number of 5/8 resin bonded ply hub laminations 2 inch in diameter. (I go to the local technical college). At the same time the 5 x 45° angled shots can be cut in the hub to depth shown, and here it is again pre-ferable to get the work done on a machine. Accuracy is important as it reduces vibration levels and consequently allows the fan to turn at higher speeds without tearing the engine apart..."

Supplementary file notes

Article.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction