24mm DC-motor gearbox for Z70-locomotive - OS-Railway

thingiverse

This is a gearbox developed to enable the use of cheap available 24mm DC-motors. It is designed to fit the original Z70 locomotive. Use first of all the Buildplate STL's, but if you need any of the individual parts they are included in the zip-files. Link to the Z70-locomotive: https://www.thingiverse.com/thing:2146425 There are two versions, one with just holes for the shafts and one with room for ball bearings. Those are the same bearings used throughout the entire system, 6mm OD 3mm ID and 2,5mm thickness. Shafts: 2pcs 3mm diameter 17mm length for transfer gears 1pcs 3mm diameter 21mm length for output gear. Nylon washers can be used to make sure the gears are not rubbing against the house walls. There are motor pinions included both for 2mm shaft and 2,3mm shafts. If you have a bigger shaft, print the pinion with 100% infill and drill to desired size. Placement of the bevel gear on the wheel shaft might need some adjustment so don't glue it in place until you find the right spot for it. Also make sure that the wheel shaft cannot move sideways, this can be done by placing nylon washers on the outside of the wheels between the wheels and the wheel bearings. There should always be some play between gears, if not they sit too tight and will heat up and even melt.