Hobby King Fokker Dr.I Triplane EPO Assembly instructions

HK Fokker Dr.I Triplane EPO (PNF) Assembly Hints
A simple model assembly outline and tips on making the bottom wing removable for easier radio
maintenance:
Note the adhesive used to join the fuselage halves on the copy I received was poor and allowed them to
separate. I re-glued the fuselage halves with 5 minute epoxy.
Tools Required: #1 Phillips screw driver, small crescent wrench, flat nose pliers, 5 minute epoxy (may
be provided in the kit), hobby knife, clear tape.
Lower wing mount modification tools/parts: 2 #4-40 x 3/8”pan head Phillips screws (or 3mm x 10mm),
2 #4-40 hex nuts (or 3mm), 5 minute epoxy, 1/8”drill, and a very short #1 Phillips screw driver (or a bit
from a modular one and small wrench to provide leverage.
Assembly:
1) Horizontal Stabilizer. Parts: Horizontal Stabilizer, 2 Control Horns, 2 control horn retainers.
Glue the horizontal stabilizer to the tail section of the fuselage. Hook the control horns onto the
elevator push rods (I left them on the outer hole) and pass through each section of the stabilizer.
Fasten the control horns in place with the retainers.
2) Center wing. Parts: Center wing, 2 wing tip struts, center struts. Glue the center wing in place
on the top of the fuselage. Glue the Center wind struts in place, seating them firmly on the
center wing and fuselage nose (alignment is important!). Glue the outer wind struts in place. Let
the glue fully cure.
3) Top wing. Parts: Top Wing, servo “Y”harness. Apply adhesive to the 4 strut cavities in the top
wing and glue it in place above the center wing. Keep an eye on wing alignment. After the
adhesive cures, run the aileron servo wires in the wing grooves and cover with clear tape. Run
the servo wires down the rear center struts and attaché with tape. Connect the aileron servos to
the “Y”harness and pass it through the fuselage forward of the elevator and rudder servos. Route

the servo wires along the trailing edge of the center wing before routing down through the
fuselage to allow space for mounting the machine guns.
4) Machine guns. Parts: 2 machine guns. Glue the machine guns into the sliots in the center wing
and 2 stud holes in the cockpit.
5) Bottom Wing Sub Assembly. Parts: Bottom Wing, 2 wing struts, 2 nut plates. Glue the 2 wing
struts into the bottom wing. Glue the 2 nut plates to the underside rear center of the wing.
6) Optional: Bottom wing modification to allow for fuselage access: Drill a 1/8”hole in the long
trailing flange at the top of each wing strut approximately ¼” (6mm) from the strut body. Pass
the screw through the bottom of the flange and lightly tighten the nut on the top side (facing the
center wing). The screw should protrude a few mm. Turn the DR1 upside down and test fit the
bottom wing. Carefully align each strut with its respective center wing receptacle and press the
strut in to create a witness mark from the screw and nut. Use the hobby knife to carve out a hole
slightly deeper than the nut in the center wing. Loosen the screws such that they are recessed
into the nut by 1-2 threads then apply epoxy to the outer edge of each nut cavity in the center
wing. Reinstall the wing, pressing the nuts into the holes via the screws. Carefully remove the
screws (do not disturb the alignment!) and let cure.
1: Bottom Wing Mount Screw and CG Location
7) Receiver Installation. Parts: SMALL 4 Channel Receiver. Pull all 4 servo leads out the bottom
of the fuselage at the bottom wing mount. Connect all the servo leads to the receiver. It is ok to
test all 4 channels are operating properly at this point. I was able to pass the receiver back
through the bottom wing mount hole and mount it against the cockpit side of the battery box. If
your receiver does not fit, the servo wires will need to be passed through to the battery
compartment and connected in that area. The receiver will need to pass through the battery box
opening.
8) Bottom wing mounting. Parts: Bottom wing assembly, 2 strut screws (if modified), 2 long wing
screws. If not modified, glue the outer struts to the center wing bottom. If modified, use the
#4/M3 screws to fasten the outer struts to the center wing, then 2 of the long screws to the center
rear (through the nut plates).
Bottom Wing
Mounting Screw
Modification
Approximate
CG Location

9) Landing Gear Sub Assembly. (Note: I re-bent the landing gear for a better fit using pliers and
crescent wrench). Parts: Landing gear wing, front metal strut, rear metal strut, axle, 4 washers, 2
nuts, 4 long thin Phillips screws. Pass the axle through the large hole in the wing. Pass the rear
strut (the one with 3 holes in each side) onto the wing and fasten with the 4 long thin screws.
Note the edge of the strut is parallel to the bottom of the wing and the top of the strut should be
approximately parallel to a flat surface that the wing is placed on. Install the front strut ensuring
its fuselage mounting surface is also roughly parallel to the rear strut. Install a washer, wheel,
washer and nut on each end of the axle.
10)Landing Gear Mounting. Parts: Landing gear sub assembly, 2 large diameter long screws, 2
large diameter short screws. Mount the landing gear with the long screws through the center
wing mount and short screws at the front of the battery box.
11)Balance Point. The forums state the CG of this model is 40-50mm from the leading edge which
corresponds to approximately the center of the outer wing strut as it meets the top wing.
12)Engine Mount and Balancing. Parts: Radial Engine, Engine Cowl, 2 short sharp screws,
modeling clay. Install a battery you intend to fly with (my 3 cell, 1300mah pack just fits) into
the battery box and install the lid. I modified the radial engine motor clearance hole such that it
clears the motor with at least 1mm to spare when I mount it on the firewall. Pack clay into the
radial engine cylinder cavities to achieve model balance (I added 40g in my example). I also
mounted the radial engine to the firewall using screws that I can access through the holes in the
cowl so I can adjust the CG by adding/removing clay to the cylinder cavities. Remove the
double sided tape backing from the front of the fuselage and install the engine cowl. Secure the
lower corners of the cowl to the fuselage sing the small sharp screws.
13)Propeller Installation. Parts: Hex nut, washer, propeller, nylock hex nut. Install the propeller
using a nut, washer, propeller, nut (in propeller hub) until secure with plenty of clearance to the
cowl.
Happy flying!