simplystupid
1 mW
- Joined
- Jul 20, 2015
- Messages
- 14
If someone has any insight on this situation and can help out, I would be very grateful.
I have tried to put together a planetary gearbox using a spare parts set for a big Bosch drill, just the ring and 4 planet spur gears.
I calculated the PCD and 0.75 mod needed for the sun gear on the motor input.
Even though there is a few rizlas worth of backlash between the meshed gears - it doesn't work, the whole gearbox casing is forced to oscillate a couple of mm.
Ring gear has 47 teeth (why so damn awkward!) - planet spurs have 16 teeth, my homemade pinion sun has 13 teeth.
Therefore the rotating planet holder has the four gear shafts on a circle, but not opposite each other. At the corners of an oblong.
Images of a Bosch starter gearbox show the same kind of geometry, so I am a bit baffled.
It doesn't jam up when turned by hand, the 13 teeth are nicely cut.
But it obviously can't be bolted to the motor as it is now.
I can remove and drill the planet shaft holes again, but any idea where?
Many thanks.
Mark
I have tried to put together a planetary gearbox using a spare parts set for a big Bosch drill, just the ring and 4 planet spur gears.
I calculated the PCD and 0.75 mod needed for the sun gear on the motor input.
Even though there is a few rizlas worth of backlash between the meshed gears - it doesn't work, the whole gearbox casing is forced to oscillate a couple of mm.
Ring gear has 47 teeth (why so damn awkward!) - planet spurs have 16 teeth, my homemade pinion sun has 13 teeth.
Therefore the rotating planet holder has the four gear shafts on a circle, but not opposite each other. At the corners of an oblong.
Images of a Bosch starter gearbox show the same kind of geometry, so I am a bit baffled.
It doesn't jam up when turned by hand, the 13 teeth are nicely cut.
But it obviously can't be bolted to the motor as it is now.
I can remove and drill the planet shaft holes again, but any idea where?
Many thanks.
Mark