Mikado 1, 2 , 3

The Mikado locomotive has been a greatly beloved loco by LGB fans from the start, being created and manufactured in 2001/2 and manufactured and delivered until 2004/6. It is the most challenging design of the LGB locomotives and the loco with the largest wheels and also the heaviest LGB loco. The engine design requires an articulated drive train. This calls for a fully suspended drive with three kardan shafts.

During the very first production series the kardan joints consisted of a star-like brass gear wheel and  a plastic pick-up which would fit this gear wheel. This type of joint was used throughout the whole drive train. The motor carried the brass star wheel connected to a plastic pick-up. At the end of the first axle there was another star-like brass gear wheel being connected to the second axle with a plastic pick-up. At the end of the middle shaft there was yet another plastic pick-up which would connect to the third and last axle that carried the star-like brass gear wheel. Huge worm drives were mounted on the first shaft very close to the motor and on the last shaft driving the first loco axle.

Basically, only the first and last axle of this locomotive were and are actually driven by the motor as the two middle axles are just coasting along, kept in sync only by the side  rods. To manage the mechanical load of the drive train two ball bearings (small = 10mm) were used in close proximity of the worm gears.

During the first series problems arose with the first plastic pick-up that was jointed to the motor: the plastic pick-up was basically pressed on the round axle with no further locking feature. This resulted in the loco to stop moving as the motor kept on running. As a consequence the plastic pick-up was improved to have a square pick-up for the axle. And the axle was altered accordingly to fit the new square pick-up.
Next, the first joint between the motor and the first kardan shaft proved to be the weakest part of the design as the plastic pick-up was not able to handle the torque of the motor and carry the mechanical load. Consequently, the joint between the motor and the first kardan shaft was completely redesigned: the star-like brass wheel on the motor was replaced by a rectangular brass bolt. The kardan shaft got a plastic pick-up shaped to fit the brass bolt.

This new design however had a flaw of its own. As the star like connection provided guidance (in the center line) for the first axle the new design did not. As the first axle tended to wobble this wobbling movement was transported to the other end of the first kardan shaft which was only kept in place by plastic guides within the motor block and its top lid. These plastic guides pretty early on wore out giving the axle more play than designed. Resulting in a  constant rattling noise from the motor block.

The ultimate and last design called for a total rework of the two motor blocks. The first and last kardan shaft were equipped with two ball bearings that now measured 12mm (compared to 10mm, see above). With the first axle being properly guided the rattling noise was completely eliminated giving the whole drive train an exceptionally smooth operation. Production numbers of the first designs vary between 500 and 800. That means that there are a lot of Mikados out there that already do or will produce one of the following failures:

• the engine runs slow or stops while the motor is audibly still working ( the first plastic pick-up turns on the axle)
• the engine simply stops with the motor running with grinding noise ( first plastic pick-up is worn out)
• rattling noise in the drive train ( plastic guides are worn out )

As you know by now: Do Not Fear- Klaus Is Near! In his workshop he reworks Mikado motor blocks, converting axles to the two-ball-bearing design. This is a precision reworking since it requires a computer controlled mill (CNC mill).  Klaus - of course - has and works on a CNC mill in his workshop as well as  (on) a CNC lathe.