Multiplex ParkMaster Pro

Multiplex ParkMaster Pro

Current Power Setup

  • Motor: Leopard 2835-7T 1160Kv, 28A max, 315W, 71g
  • ESC: Castle Creations Talon 35A with 7A BEC
  • Prop: APC 11×4.7 Slow Fly
  • Batteries: Tattu 3S 1050mAh 75C 96g and Turnigy Nano-tech 3S 1.0Ah 45-90C 93g

Current Radio Gear

  • Transmitter: Spektrum DX18 G1
  • Receiver: Lemon Rx DSMX-Compatible 6ch Diversity, 4.54g
  • Servo, Ailerons (2): Hitec 65HB with 6″ extensions
  • Servo, Elevator: Hitec 65HB with 9″ extension
  • Servo, Rudder: Hitec 65MG with 9″ extension

Current Specs

  • Wingspan: 975mm (38.4in)
  • Flying Weight Minus Battery: 473g
  • AUW: 569g with Tattu 1050mAh 75C 96g
  • CG: 110-120mm
  • Flight Time: TBD
  • Thrust: ~1600g with Leopard 2835-7T

Manuals, Specs and Instructions

Powerplant
My ParkMaster 3D has a 2:1 power-to-weight ratio and flies well. It will hover toward the end of a battery but punching out of a hover and authority in knife edge loops could be better. So with the ParkMaster Pro, I wanted to find a little hotter motor than the Emax GT2218/11 in my 3D. I was able to find Cobra and Leopard motors with promising specs but the Cobra motor seemed to be discontinued so I went with a 71g 315W Leopard 2835-7T, which should net a 3:1 power-to-weight ratio on the Pro.

Motor Thrust Angles
Multiplex is one of the few RC plane manufacturers that include detailed setup and tuning procedures in its manuals. The ParkMaster Pro Manual is no exception and includes Center of Gravity, Balancing, Level Flight, Side-thrust, Down-thrust and Aileron Differential. Typical fixed-wing motor thrust angles are a few degrees down and a few degrees to the right. This particular ParkMaster Pro did not want any down-thrust and a few degrees side-thrust to reduce motor torque, mostly in a hover. I will fine tune this more as I fly it.

Electronic Speed Controller
If spending close to a $100 for just the airframe of a 3D foamy, it doesn’t make sense to skimp on electronics. Arguably one of the highest quality and most well known ESC line is produced by Castle Creations. Castle’s Talon Line includes a 25A and 35A. Due to the 28A 315W motor and higher air temperatures typical of flying RC models in Arizona, the Talon 35A with 7A BEC was selected for this build. The Talon 35A ESC also has a longer receiver cable that reaches the ParkMaster Pro receiver bay without an extension. The receiver cable on the Talon 25A is shorter and would need an extension.

Castle Creations Talon 35A with 7A BEC
Castle Creations Talon 35A with 7A BEC on the ParkMaster Pro

Talon 35A ESC Settings
I used default settings on the Talon 35A ESC except for Motor Timing and Throttle Calibration, as follows:

  • Cutoff Voltage: Auto-LiPo
  • Auto-LiPo Cutoff Volts/Cell: 3.2V
  • Cutoff Type: Soft Cutoff
  • BEC Voltage: N/A
  • Motor Timing: Low (default is Normal)
  • Motor Direction: Forward
  • Throttle Type: Fixed (default is Auto Calibrate)
  • Brake: 0%

With Motor Timing on Normal, the Leopard motor was too hot to hold for more than 3 seconds after a 5-minute flight so I changed it to Low. For some reason Throttle Type on Auto Calibrate would not work correctly with my Spektrum DX18 transmitter. The motor would run on the lowest throttle position when plugging in a battery and I had to perform an ESC calibration every battery change. Switching Throttle Type to Fixed corrected this and the ESC retained calibration.

Castle Talon 35A ESC Specs

  • Input Voltage: 2S-6S
  • Max Continuous Ouput: 35A
  • BEC Voltage: 5.5V
  • BEC Output: 5A cont., 7A max
  • Weight: 27.8g w/wires, no connectors
  • Fully programmable and firmware updatable

Receiver
I currently own 6 Lemon Rx receivers from satellites to stabilizers and have never had a problem with them. So I went with the lightweight Lemon Rx DSMX-Compatible 6ch Diversity Receiver, P/N: LM0034 in the ParkMaster Pro and installed the antennas in plastic tubing that I embedded into the foam. See installation details at the link below.

Lemon Rx Receiver Installed
Lemon Rx Receiver Installed in Receiver Cavity of ParkMaster Pro

Prebuild and Quality Issues
I ordered my Multiplex ParkMaster Pro kit from Tower Hobbies. The first kit received looked like a customer return, with pieces displaced in the packaging that could only have been if the box was opened. Some parts had chunks removed that were not in the box. Unfortunately I have had similar results with my last few models from Tower Hobbies. So the first kit went back. The second kit received was better but far from perfect. The fuselage had areas where the foam was not completely filled. I reluctantly kept this kit. The tail section of the fuselage was the worst and required attention before assembly. I used thick packing tape to reinforce and may need to add additional reinforcements later. Quality of the ParkMaster Pro kit from Tower Hobbies was a disappointment and not what I expected from a kit that cost $103.99.

Multiplex ParkMaster Pro Fuse Tail Section

The photo above shows the channel for the carbon-fiber strip that was not completely infilled in the molding process. Every channel on the fuselage was this way to varying degrees. The foam aft of the tail servos was very sparse and needed to be reinforced.

Decals and Paint Embellishment
I like the fact that Multiplex includes uninstalled decals with its ParkMaster kits. Like most folks, I did not care for the decals on the older ParkMaster 3D so I painted it. The decal set that came with the ParkMaster Pro is much nicer so I used it. Multiplex includes checkerboard style graphics for the bottom but I wanted more contrast for orientation so I embellished them slightly by adding stripes on either side of the graphics with black acrylic latex brush-on paint.

Painted Stripes on Bottom
Painted Stripes on Bottom of Wings, Stabs and Control Surfaces

Painted Stripes on Bottom

Landing Gear Modification
Multiplex upgraded the landing gear on the ParkMaster Pro to carbon-fiber flat stock. The ParkMaster 3D had wire gear, and although resilient, would allow enough flex on high alpha “plop-downs” for prop strikes. If you flew the ParkMaster 3D, you know this could result in having to glue the nose back on the fuselage. For the ParkMaster Pro, Multiplex redesigned the motormount to be one piece. So this along with stiffer carbon-fiber landing gear should reduce the chance of this happening. I took it a step further and modified the carbon-fiber pieces to be removable and replaceable, as shown below.

ParkMaster Pro Landing Gear Mod, Upper

The above photo shows the two halves of the landing gear mount before being glued together and installed in the fuselage. I clamped the two pieces together and drilled holes on either side and through the carbon-fiber slats.

ParkMaster Pro Landing Gear Mod, Upper Screw Hole
ParkMaster Pro Landing Gear Modification, Upper Screw Hole
ParkMaster Pro Landing Gear Mod, Lower
ParkMaster Pro Landing Gear Modification, Lower

Tailwheel Modification
Similar to the ParkMaster 3D, the Pro did not come with a tailwheel and is meant to just drag on the ground. I fabricated a lightweight steerable (via rudder) tailwheel assembly using a landing gear from an ultra-micro T28 Trojan and a lightweight wheel from a 3D profile foamy. I added carbon-fiber rod with CA and heatshrink tubing to the spring steel wire to make it stiffer and handle the extra weight of the ParkMaster tail section.

Multiplex ParkMaster Pro Tailwheel Mod
Multiplex ParkMaster Pro Tailwheel Modification

Build Order
You might have noticed that I installed most of the electronics before glueing the wing and tail section to the fuselage. It is much easier working on the fuselage while lying flat on a work surface. Basic build order was landing gear mods, paint and decals, electronics, glue wing and tail section, control surface hinges and control linkages.

Close-ups, Feedback and Reviews
To be more mobile friendly, photos on TazRC are limited in size. I would be happy to post any close-up photos on request. Just leave a comment below. Also, feel free to leave your feedback or personal review on the Multiplex ParkMaster Pro. Registration not required.

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