03. LEGO L-motor gearbox modification

As requested here, here's an instruction video (made up of still photos taken after the event) of how I modified the LEGO L-motors for my DP1 model, so that the motors run 4.9x faster. The 2nd stage of the epicyclic gearbox needs to be bonded together (and its outer planet teeth removed), thus taking it out of the gear chain.

 

ATTEMPT AT YOUR OWN RISK!!

 

NOTE: I tried to make a jig to enable the housing to be taken apart without permanently cutting the plastic, but without success. Despite carefully aligning aluminium prongs filed from 1" sq angle, and assembling into a solid vice-like construction, it only served to crush (not quite permanently, thankfully) the whole motor. Damn!

 

TEETH INFO: L-motor epicyclic gearbox teeth -

Sun - 11T

Planets - 16T

Ring - 43T

The outer ring is stationary, reduction is achieved by driving the sun, the output of each stage is the planet carrier.

Done