Peppi

1370mm Crash Resistant Power Trainer / Sports Aerobatic .20 - .38 cu in. Power Model

Designed by Stan Yeo

Produced by PHOENIX MODEL PRODUCTS

Introduction

Peppi is a crash resistant basic power trainer that will take the budding radio control model flyer from the first tentative steps up to and including BMFA 'B' certificate standard. EPP (expanded polypropylene) has revolutionised learning fly radio control gliders, now it is the time for power flyers to enjoy the benefits of its quick build time and less stressful flying. Few EPP models are pleasing to look at or build but they do allow modellers to enter the hobby in a less painful way. The accessories supplied in the kit are as used in the prototypes and more than up to the job they have to do. Likely damage in the event of a serious mishap are a broken propeller, engine mount and wing dowels so it is worth having spares. Wing dowel breakage can be avoided if a thicker dowel is used but we prefer the dowels to break, which are easily replaceable if not glued, rather than some other part of the structure which would be more difficult to repair. Items not supplied in the kit include adhesives, radio control equipment, engine, spray adhesive (used as a pre-treatment before covering) and coloured vinyl tape (used to protect covering from ultra violet light and decorate the model). We can supply all of these items at competitive prices so please ask if you need them.

Tools / Materials Required

A limited range of tools / equipment is required to build Peppi. These include a Scalpel with a supply of spare blades, 180 grade glasspaper and a soldering iron. Glues used are Impact Adhesive such as Evo-Stik or Bostik, 12 minute Epoxy and thin Cynoacrylate (superglue). Impact adhesive is used for all joints unless otherwise stated. Also recommended is Spray Adhesive for priming the EPP before covering with the CW tape and coloured vinyl to decorate the model and protect the CW tape from UV light degradation.

R/C Equipment

A 4 channel radio control set with 3/4 servos and rechargeable batteries on 35mHz is needed to fly Peppi. These start at around £90. Modern electronics is very reliable so reliability is no longer an issue. We stock and recommend one of the following as ideal starter sets, Hitec Laser 4, Futaba 6EXA.

Building the Fuselage

1. Lightly sand the fuselage and doublers with 180 grade wet and dry. Remove dust with a small brush or vacuum cleaner.
2. Join fuselage side nose and tail sections using impact adhesive. Use ply nose doubler to aid alignment.
3. Attach ply nose and tail doublers to fuselage side ensuring there is a left and right side.
4. Shorten nose of RIGHT side by 1.5mm to allow for engine right thrust.
5. Drill 4.5mm wing dowel and undercarriage dowel holes.
6. Mark position of F2 and Superglue 10mm triangular strip to doublers to reinforce doubler to undercarriage joints and doubler to engine bulkhead joints.
7. Mark and drill 4.5mm dia. holes in engine mount bulkhead for engine mount.
8. Fit engine mount to bulkhead using 4BA screws and 'T' nuts. Tighten screws to embed 'T' nuts into ply. Cut off excess screw thread to avoid puncturing fuel tank. Drill hole for throttle control cable (see plan). Remove engine mount from bulkhead.
9. Drill 3mm dia. hole for throttle control rod in former F2. See plan for position.
10. Position fuselage over plan view of fuselage and fit former F2 (use epoxy) and block B2 (superglue). Position block B1 but do not Superglue. Ensure fuselage is square.
11. Epoxy engine bulkhead and undercarriage mount in position.
12. Superglue 6mm sq. strips to either side of SINGLE thickness tailskid at front.
13. Join fuselage at tail, sandwiching tailskid between doublers as per plan and Superglue.
14. Fit EPP fuselage bottom and trim to size using sharp knife. Cut foam using a slicing action.
15. Fit EPP fill-in forward of undercarriage mount.
16. Cut hinge in Fin and tailplane by removing one side of Correx flute along hinge line. Mark centre-line of tail on top surface. Draw a line either side of the centreline, parallel to it 2mm away from it.
17. Using Superglue glue a length of 10mm triangular strip, starting at the hinge line, to one of the 2mm lines. Cut to length. Lining up the control surface hinge lines glue the Fin to the triangular strip just fitted. Fit triangular strip to other side of Fin base.
18. Glue tailplane assembly to fuselage ensuring it is square.
19. Fit Rudder, Elevator and Throttle servos using Blocks B3,4,&5 as servo bearers.
20. Determine which side of the servo the rudder and elevator control cables are going to be attached. (Note: changing sides changes direction of control movement). Draw proposed route on plan in pencil. Mark position of control cables on block B1 and drill 3mm dia. Holes. Superglue in position.
21. Fit control horns to rudder and elevator as determined above.
22. Fit metal control links to cable adapters and fit to control horns.
23. Relieve foam fuselage top to accommodate triangular strip at bas eof fin and masking tape fuselage top in position.
24. Determine exit positions of control cables from foam. Make an allowance for control cable movement (10-12mm between end of conduit and cable adapter).
25. Fit control cables conduits. This is done from the rear by heating the last 10mm of the straight end of the throttle control rod and burning a hole through the foam taking care to keep the hole to the size of the control cable conduit. Practice on waste foam.
26. CW tape control cables to inside of fuselage.
27. Solder cable adapters to end of control cables. Superglue conduit to block B1 and cut to length i.e. 10mm beyond B1.
28. Centralise servo and attach 'Z' bend rods to servo arm.
29. Fit control cables and attach to control horns. Set control surfaces to neutral and cut control cable to length by marking with felt tip pen and removing cable for cutting. Allow 25mm between end of conduit and end of cable. It is easier to cut the cable if the cable in tinned (soldered) in the area of the cut.
30. Refit control cable, reset controls to neutral and cut 'Z' bend rods to length. Leave 1-2mm gap between end of rod and end of cable for adjustment.
31. Clean ends of cable joiner tubes and solder 'Z' rod and control cable together.
32. Un-solder and remove cable adapter from control surface end of control cable. Whilst solder is still molten wipe cable with a rag or tissue to remove surplus solder so end of cable can slide into conduit. Remove servo arm from servo and slide control cable back into cable conduit.
33. Fit throttle control conduit.
34. Fit fuel tank. Ensure that 'clunk' is just clear of the end of the tank and free to move.
35. Fit top EPP fill-in between engine bulkhead and F2
36. Block control cable conduit exits with rolled up paper and spray fuselage with spray-on adhesive. Leave to dry for 5-10minutes.
37. In high stress areas such as the end of the ply nose doubler and in front of the tailplane apply an extra layer of CW tape before final covering.
38. Cover fuselage with CW tape, overlapping each strip by 10mm and extending tape to cover engine bulkhead (acts as fuel proofer).
39. Cut dowel holes in CW tape.
40. Cover fuselage with coloured vinyl tape again covering engine bulkhead. Cut dowel holes and fit wing / undercarriage dowels.
41. Mark position of engine mounting screws on engine mount and drill 5/64in (2mm) dia. pilot holes.
42. Fit engine mount and fit engine with 12mm x No. 2 self tapping screws.
43. Fit throttle control push rod. It may well be necessary to bend pushrod at motor end to achieve free movement.
44. Remove paper plug in ends of control conduits and refit servo arms after neutralising servos. Re-solder cable adapters to control cables ensuring control surfaces are in neutral.
45. Assemble undercarriage as per plan and fit undercarriage using elastic bands.

Building the Wings.

Rudder Elevator ONLY Wing

1. Lightly sand wing surfaces and remove dust as before. Remove waste from wing spar slots.
2. Laminate the 2 x 1.5mm dihedral braces using Superglue. Mark centreline.
3. Superglue dihedral brace to mainspars ensuring first spar is lined up with centreline and at correct dihedral angle (see plan).
4. Fit plastic trailing edge stiffening. Check centre joint is aligned when wings set at correct dihedral angle. Adjust as necessary.
5. Epoxy mainspar to one wing panel. Align top edge with top surface of wing. Use masking tape to hold wing together whilst epoxy sets.
6. Join second wing panel to first, again using epoxy and aligning mainspar with top surface of wing. Check wing has correct dihedral angle.
7. Spray wing with adhesive and allow to dry for 5-10 minutes.
8. Cover wing using CW tape and starting at trailing edge as shown on the plan. Overlap each layer of tape by 10mm. Overlap tape at wing joint 100mm either side of joint.
9. To protect the CW tape from ultra violet light and decorate the wing cover top surface with coloured vinyl adhesive tape or any other opaque, thin, sticky back plastic of your choice.

Aileron Wing

1. Lightly sand wing surfaces and remove dust.
2. Fit hardwood rear spar and cut to length. Hold in position using masking tape whilst adhesive dried.
3. Remove foam from mainspar slot. Mark centre of spar brace and attach to mainspars. Carry out dummy assembly of wing.
4. Epoxy mainspar to one wing panel aligning top of spar with top surface of wing. Use masking tape to hold wing together whilst epoxy sets.
5. Fit second wing panel to spar and join with first wing panel as before.
6. Masking tape 12mm balsa sheet centre section TE in position and mark location of aileron torque rods. Note when assembled there is a gap of 20-22mm between the torque rods.
7. Cut out recesses in trailing edge to accommodate torque rods and epoxy in position taking care not to let epoxy 'freeze' torque rods in their tubes.
8. Shape trailing edge to follow wing section but keep TE at least 1.5mm thick at edge.
9. Cut out a cardboard rectangle slightly smaller than the base of the aileron servo. Use this template to cut a rectangular hole behind the mainspar for the aileron servo. The aileron servo should be a tight fit in the hole. Check servo fit and then remove.
10. Spray wing with adhesive and allow to dry.
11. Cover wing with CW tape starting at TE as per instructions shown on plan. Overlap covering by 100mm either side of wing joint and each strip by 10mm.
12. Using 180grade sanding block bevel nose of ailerons. Lightly sand top and bottom surfaces and remove loose dust using a vacuum cleaner.
13. Hinge ailerons using CW tape. CW tape aileron to torque rod (see plan). Cover top surface of hinge and CW tape around torque rod with vinyl tape etc. to prevent UV degradation mentioned previously.
14. Cover aileron using self adhesive vinyl tape or the sticky back plastic covering used earlier.
15. Assemble aileron push rods as per plan ensuring control surfaces are neutral with aileron servo centralised.

Flying

The following notes are in no way comprehensive but form the basis of an elementary check-list. It is strongly recommended that you join a local club and seek their help and guidance. Do not attempt to fly without third party insurance. The British Model Flyers Association (BMFA) Tel. No. 0116 244028 will be able to provide you with details of your local club and can provide third party insurance at nominal cost.

Flight Preparation

1. Check all controls operate in the correct sense:
   • The Elevator goes down when the control stick is pushed towards the top of the case.
   • The Rudder moves to the right when the control stick is moved to the right
   • The right Aileron goes UP when the control stick is moved to the right.
   • The Throttle is fully open when the throttle stick is pushed forward towards the top of the case.
2. Assemble the model. Check the balance point is 65mm +/- 5mm back from leading edge (fuel tank empty). Adjust as necessary by adding weight to the tail or placing weights underneath fuel tank.
3. Check flying surfaces for warps (twisting). Warps can be removed in the wings by twisting the wing in the opposite direction and re-smoothing the covering using a warm iron.

Flying - Some common problems

Again these notes are deliberately brief. It is not possible to cover all aspects of model flying in the building instructions so if you are inexperienced please seek help.

1. . Model noses over on take-off. Hold in full up elevator until model starts to lift-off then return elevator to neutral. Bend undercarriage in to increase propeller ground clearance.
2. Model does not track straight on the ground or is difficult to keep tracking in a straight line. Possible causes misaligned undercarriage, rudder control surface out of trim, incorrect sidethrust or model not being directly into wind for takeoff. Check U/C alignment, neutralise rudder ensure model is taking off into wind. If problem still persists put toe-in on undercarriage and or use rates to reduce the sensitivity of the rudder on take-off but restore full rudder control when airborne.
3. Model wants to climb continuously but when the throttle is closed or the engine cuts model dives. Not enough downthrust on engine or balance point too far back. Check balance point and move forward if necessary. Pack up back of engine with washers and try again. If still insufficient pack engine mount.
4. Model requires an excessive amount of down trim or up trim. Likely cause fuselage has been 'bent' during covering resulting in incorrect wing tailplane incidence angles. Check wing tailplane incidences with plan and adjust as necessary by recovering the fuselage (remove tape carefully with hair dryer) taking care not to pre-tension the CW tape.
5. Model 'tip' stalls i.e. drops a wing when slowed down. Possible cause a warped wing, (see above) or trying to fly too slowly.
6. When looping into wind, wings level, the model 'corkscrews' out of the loop. Most likely cause, other than a warped wing, rudder not trimmed to neutral. Note direction of screw and adjust rudder trim. Try again ensuring model is pointing into wind and the wings are level throughout the loop. Repeat until satisfied.
7. Engine sidethrust needs adjusting if, in a steep climb into wind, the model drifts to the left (more right thrust) or right (less right thrust) as the speed drops off.
8. Model dives during a roll. Insufficient down elevator during the 'inverted' phase of the roll or lack of speed. Ensure model has sufficient speed to carry out the roll and start the roll with a slightly nose up attitude.
9. Model dives in a turn. Most likely cause not enough up elevator applied in the turn. Watch the fuselage during the turn, keep it level.

Finally should you require further assistance or advice please contact us either by letter, telephone, email or visit our website (http://www.phoenixmp.com) where you can find lots useful information and our full catalogue.

Happy flying

Stan Yeo

Peppi 040502