It is a spur gear 3D model collection for 3D print gear mechanism designer.3D models were generated in a gear desing software and the involute geometry is very fine.You can design lots of gear ratios bye using this gears.Gears are designed in a metric 1 module. There is no addendum modification in gears so in your designs you can easyly calculate axis distance of gears.Properties of gear set is given as belowmodule: 1number of tooth: 10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25facewidth: 3 mm (it is a solid model step file so you can open it with any kind of 3D CAD program and change the facewidth)pressure angle:20 degreesaxis distance=((toothnumber gear1+toothnumbergear2)xmodule)/2in this formula our module is 1 so it is just((toothnumber gear1+toothnumbergear2)/2If you need another type of gears such as bevel gears and helical gears or worm gears please contact directly.I can generate your 3d printing gearbox gear models according to your needs also.