Pneumatic Backhoe

Almost 15 years have passed since the release of the last pneumatic backhoe, the legendary 8455.

This model is bigger than the 8455 but not as big as the biggest official sets (it has about 1600 parts). As the 8455, it is a push-and-play toy with all major functions implemented with pneumatics. However, the pumps are motorized in this model.

Pneumatic features:

• backhoe bucket curl
• backhoe boom elevation
• backhoe dipper/stick in-out
• backhoe boom swing
• stabilizers
• loader boom elevation
• loader bucket curl
   

Other features:

• four-wheel steering with Hand of God and working cockpit steering-wheel
• pendular front axle
• rotating seat
• opening bonnet

The model is not based on a particular machine and it's made in the style that's more common in the USA than is Europe: the backhoe boom is centered and fixed, but the stabilizers have wider base.

The model is big enough to hide the tubes so the cockpit is not crammed with tubes.

Controlling:

The pneumatic switches are placed on the sides of the model. They are easy to reach and to operate carefully, but hidden enough not to be visually distracting. There are two separate circuits on each sides, so two functions can be operated at a time with two hands without the functions affecting each other.
The functions are grouped together in a convenient way for a right-handed person. Backhoe: left hand for swinging and dipper elevation, and right hand for boom elevation and bucket curl. Loader: left hand for boom elevation and right hand for bucket operation. Of course, the model can be easily modified for a left-hand setup.

Front axle and steering:

The first axle is pendular: not a rigid axle as in real life, but an independent suspension with the two arms connected with a beam. The wheels stay more vertical and more away from other parts which is important as the things between the wheels are already as narrow as possible. Another advantage to a rigid axle is the stronger chassis and wheels support.
The wheels still touch parts when fully steered but there's no jamming or noticeable resistance: the front wheels can touch the arm elevator cylinders and the rear wheels can touch 1-1 rollers placed there deliberately to prevent the wheel from jamming into beams there

Check out the video demonstrating its main features:

This model would be a good opportunity to introduce slightly bigger buckets.