Tamiya TB-02D DriftSpec chassis build

Although Tamiya's TT-01D chassis is very popular amongst r/c drifters (based on my WWW research), quite possibly due to it's general availability and the value for money it offers, I decided to go for the more expensive TB-02D as it has a number of features I wanted. Specifically, a metal prop shaft, oil-filled dampers, ball diffs and (perhaps most importantly) Tamiya's new "Super Driftech" tyres - more on those later.

As far as I can tell, the TB-02 (no 'D') is an end-of-life product. Tamiya apparently decided to modify it specifically for drifting, though, and use it as a launch platform for the abovementioned DrifTech tyres. The official product description and photos can be found at http://www.tamiya.com/english/products/49458tb_02d/index.htm

To the best of my knowledge this chassis is not sold in Australia. I purchased mine from an eBay store in Hong Kong (user ID hongkong_cowboy). As fate would have it, it arrived on Christmas eve. See the following photos, and note that the shrinkwrap is still in place on the first one - such self control :-)

Part-time assembly ran from late on Boxing Day to Saturday morning 29th, when the electrics (including LEDs) were completed. As with other Tamiya products I've worked on, the assembly instructions were clear, but a little too concise in places where more detail would have helped. For example, fitting the tyres to the rims required that I soak the tyres in hot water (as hot as I could stand with bare hands) and use of a vice - which is a lot more than the "fit into grooves, apply instant cement" offered by the manual. The instant cement, by the way, is superfluous.

I deviated from the instructions in some other ways, too:
- ceramic grease was added to the motor pinion and propshaft spur gears
- the radio receiver antenna wire was run around the chassis rather than into a whip protruding from the body
- ball joints supplied with the TRF dampers replaced the standard chassis items
- the front body mounting posts were installed so the snap-pin holes ran north-south rather than east-west.

Additionally, impact absorption was added to the sides of the tub (to support the body), and padding around the battery bay.

The assembly instructions set the suspension geometry for drifting:
- negative camber on the rear wheels, none on the front
- toe out on the front wheels, none on the rear (without aftermarket mods, the rears have no toe adjustment anyway)
- wider track on the front than the back (by use of a spacer in wheel hubs)
- firmer spring settings on the rear than the front.

At first it displayed a strong tendency to understeer. I corrected this by tightening the rear diff. See the following photo for the section of the instructions that shows how the ball differentials are assembled. The amount of slip is controlled by the tightness of bolt & nut MA14/MA15. I found that less than half a turn did the trick.

The resulting chassis is shown in the following photo. I've tried it with both the Type D (fitted for this photo) and DrifTech tyres and, trust me, it drifts! (especially with the latter) :-)))))