Tamiya Rally Beetle Project

Page 1: Assembly

This build was a quick one: I finished it in a single long evening (not counting painting). The model is quite simple and comes in a box barely larger than the body shell. The box art is a photograph rather than the more traditional art. Inside the box is a pile of sprues, some hardware bags, the usual tools, instructions, masks, and stickers. There is also a Torque Tuned 25T motor and a TBLE-02s speed controller. The kit uses plastic bushings but I immediately built the model with full ball bearings.

The build begins with the front and rear gearboxes. Because the model can be built with multiple wheelbases, the gearboxes are modular and just need to be bolted to the chassis center sections. Each gearbox houses a plastic bevel gear differential with the rear also containing the motor mount. The front encloses the steering assembly. The servo is almost totally encapsulated. I used a metal gear waterproof Savox servo which is complete overkill for this model but I happened to have it lying in my parts box from another model. There are no bellcranks, the links attach directly to the servo saver on the spline. The short wheelbase version uses a single long chassis plug, the medium uses both a long and a short chassis plug, and the long uses two long plugs. I've got the long version. It is really important to make sure the screws are quite tight because all structural loads are carried between these body plugs and they are only supported with 4 screws each. Different length prop shafts are needed to connect the front and rear gearboxes depending on what length you are using. The kit only comes with the long shaft.

The stock steering is really bad. There is huge amount of wobble in the servo saver. I was able to remove most of the play by selectively sanding the servo saver parts until they clamp together more tightly. Not sure why Tamiya designed it so loose. The right hand image shows the completed suspension with the body posts attached.

Here is the front and rear suspension. They like to call these things "friction dampers", but really neither word applies. There is no friction here except whatever is inherent in the shafts. There are no rubber sleeves or any other internal features to add friction. There is therefore no damping either. These are really just spring guides. On pavement that's actually good enough but on even moderate gravel you'll see a lot of bouncing. The front suspension arms are very short: less than an inch. This means hardly any suspension travel. The model can be built with two ride heights depending on which hole you use to attach the C-hub to the lower arm. The difference is probably 5mm.

I used a white painted TEU-105BK extracted from my Dark Impact because I wanted to save the brushless capable controller for something else. The paint on it is ugly but can't be seen with the body shell in place. The battery mounts crosswise and the length is adequate for a LiPo. The tires are directional with a different inner and outer side tread so you need to make sure you install them right. There are no tire foams. The manual says to glue the tires, but there is no reason whatever to do so. There is no way they are coming off with the power of this model.

Up to Index | Go to Page 2