The Lego Technic Bulldozer used in the recent build articles is now available for sale, fully built.

The price is £120 including P&P and a set of batteries.

http://www.technic-scotland.co.uk/Shop.html#8275-Built

The Lego Technic Bulldozer was one of the most complicated and detailed Lego models I've built.  My last build was the Lego Technic Crawler Crane (set 8288) - (more on that sometime soon) which was relatively straight forward and uncomplicated.

The first part of the build (manual 1) dealt with the basic drive train.  This was very detailed and after 4 hours of building I'd nothing much to show for it.

The second part of the build (manual 2) took the basic drive train and added a few motors and all the body work.  This is an area Lego didn't really used to include in their models. This part of the build was less complicated from the first, but did still take time and I did make mistakes.  When completed I couldn't resist adding batteries to remote control and having a wee play.

The third part of the build ad’s on the front blade and rear ripper blades.  This bit was easy and enjoyable - mainly because after a short time I'd ended up with something substantial.

The Lego Remote Control

This is the first model I've seen with any kind of remote function.  At the beginning of the build I was unsure if it was a radio or infrared remote control.  Unfortunately it turned out to be infra red control.  This means that you have to be able to see the model in order to control it.  I'd intended to attach a small camera to the driver’s seat and to see it that way.  Full radio controls don't cost much these days and it would have been a much more advanced model with this.  The radio controls would also have been excellent to build in to other models. 

The infrared does work well though.  This model comes with 1 controller and two receivers.  The controller supports up to 4 receivers, changeable by a switch on the controller.  Just don’t change channels when operating one of the leavers as the motors will continue to run

The motors are either on or off though unlike a normal radio controlled model.

The Remote controller is part 8885 ans is currently available direct from Lego at £7.35.  The Remote Control Reciever is part 8884 and is currently £11.25 direct from Lego.

Tracks

The model uses 2 XL motors to drive each track.  Only the right hand track is connected to the V6 engine however, and this appears to make the bulldozer veer off to the right.  The right motor has more resistance than the left, so runs slower.  A more efficient way would have been to use an adder subtractor gear train method of arranging the tracks.  Using two differential joints, one motor controls forward and reverse, one motor controls left and right movement.  More information is available here - http://www.br-eng.info/my-lego-roscomenu-29/my-mocs-roscomenu-43/45-other/113-adder-subtractor

Front blade

I had expected the front blade to go lower and to lift the model up at the front.  The rear ripper manages to lift the back up however.

Front Blade Fully Down	Rear Ripper fully Down

Lights

As the model has power it would have been nice to have real lights on the front.  Small lights are available as part of the Power Functions Motor Set (8293)

Manuals

There's 3 separate manuals - this is obviously to keep the overall thickness down.  The manuals are well designed and accurate.  I particularly like the 1:1 drawings to make sure the gears are placed in the correct location on an axle.  Some bits could do with red arrows pointing exactly where a pin or axle should go, and where they show the length of the studless bricks, they don't show the studded bricks.

Alternative Model

The box shows an alternative model for the set, but I still haven't been able to locate instructions for it.

Conclusion

Overall it was an enjoyable build, with useful parts and interesting engineering.  I can’t wait to get my hand on the new Lego Technic Crane Truck!

The Lego Technic Motorized Bull Dozer Build

Introduction
Build Part 1
Build Part 2
Build Part 3
Build Review
Final built model available for sale