Next Level mini truck, Akihabara Tokyo.
specs & features
1/20 scale 1993 Nissan King Cab by Lindberg
Full working suspension controlled by 3 micro servo's
Micro drive motor, drive train, U-joints and working rear axle
Working 5 stage aluminum Z-rack powered by 5 micro servo's
MP3 and speaker setup
RC controlled lights including signal, parking and brake lights.
Custom made 15" wire wheels with stretched tires
Custom paintjob by Francisco Pancho Barron
I have build 1/25 scale bed dancing mini trucks before but the plan for this 1/20 scale Nissan King Cab mini truck is to take it to the next level.
Creating a full function RC mini truck bed dancer with working Z-rack, MP3 player and lights was my mission.
As usual I spend a lot of time behind the computer searching for photo's and videos figuring out the design and functionality as well as looking for usefull parts.
In 2006 my good friend the late Brian Archuletta send me this Lindberg 1993 Nissan extra cab mini truck kit.
I started out creating the Z-rack using styrene plastic and went with a configuration that enabled the bed to tilt side ways and lift it to an impressive height.
It proved that the styrene rack had too much flex so I used aluminum sheet metal instead and cut the individual stages.
I wrapped the chassis to reinforce and make it stiff enough using sturdy styrene sheet material.
polystyrene z rack on the mini truckWhen I started out building this Z rack beddancing mini truck I used a 1.5mm styrene sheet, tubing and flat bar. It proved to be to flexible and not ideal to rock the bed.
folded out polystyrene z rackCreating the polystyrene z rach wasn't a complete waste of time at least I had a good template to work from creating the aluminum version.
jig saw cutting the z rack stagesI used a jig saw to cut the four different stages out of 1.5mm aluminum sheet material. Aluminum is light weight and super stiff which makes it the ideal material to create the stages for the z rack.
aluminum z rack with cylinderDownside is that you can't solder alu part together so I had to use super gleu to mount the tube hinges.
mock up of the z rack bed setupHere's the z rack all put together with cylinders mounted and hooked up to the servos that sit behind the front seats in the cabine.
For this mini truck beddancer I created realistic looking hydraulic cylinders in combination with a strong fishing line tht runs through steel spring tubing.
I used aluminum tubing with a rivet on the end to make sure the braided fishing line runs smooth and lasts a long time.
For the cylinder's I didn't want to go with micro servos mounted to the individual stages of the rack so it took four more years before the coin dropped on how to create working cylinders after seeing one of Marcos Lopes A-arm hopper cars.
To create the ram I used a paperclip and glued the fishing line to the end that sits inside the cylinder.
The 1.5mm spring tubing is made by Japanese Wave Company called A-Spring. The fishing line runs through the spring tubing to the micro servo where the line is attached to the servo's arm.
When the servo's arm turns 180 degrees the line pulls the ram out of cylinder.
fake hydraulic cylinder and ramI used a piece of styrene for my first cylinder with a rivet inside to make sure the line runs smooth.
assambled styrene hydraulicThe Spider wire fishing line runs through the spring tubing over the edge of the rivet and inside the cylinder.
assambled hydraulic cylinderSpring tubing running on the outside of the cylinder toward the top where it meets the rivet.
Drivetrain & Suspension
Next step was to get this Nissan Hardbody mini truck on the road adding a 10:1 ratio micro gear motor, drive train and working rear axle.
I used the kits rear axle housing and installed a slot car crown and pinion gear. The U-joints I found in Japan and are used on HO model trains, the size is perfect and they work flawless.
Instead of trailing arms I went with an original one leaf spring setup made from thin steel and brackets and shackles made of brass and aluminum.
The front suspension consists of a brass bar with spindles and micro servo placed in the middle that slides up and down in the shaft that is mounted on the chassis. It's a pretty basic setup but it works flawless and never let me down so far.
Drive train and gearsI used the original rear axle that came with the kit and added brass tubing for the axle to run through.I ordered the smallest Scale trix gear and pinion I could find and they fit perfect inside the pumpkin.
Universal joint and gear housingThe universal joint I bought at a model train store in Japan. The two parts snap together and are made out of tough plastic.
Assambled rear axle with drive shaftBefore I installed the rear axle I did a test to see if the U-joints worked well enough under different angles. The mini truck is powered by a N20 gear motor with 10:1 gear ratio running at 5V.
Gear motor mounted and drive shaftI soldered a brass strip on the N20 gear motor and mounted it on the chassis with tiny screws.
U-bar front suspension with steeringI wanted to create a basic, hassle free front suspension using a U-bar slider. In the center I mounted an ultra micro servo for steering.
This mini truck has so many working features that it was a huge challenge to pack everything inside and around the cabine area.
I used an Turnigy 8 channel receiver, removed the casing and all the parts that weren't absolutley necessary. The mini truck has well over 10 functions so I added a RC switch to switch from suspension mode to bed dancing mode both setting have overlapping functions.
A tiny USB stick sized MP3 player was added and connected to a amplifier and micro bass speaker that fits under the dashboard. Four tiny button on the center consule operate all the MP3 players functions.
In the end all the parts fit together and the system is powered by a 3.7V 1000Mah Lipo Battery.
A micro voltage booster is used to squeeze 5V out of the 3.7 lipoly battery so the servos get more power and work faster.