Step 8: How to Modify a Servo Motor for Continuous Rotation ( One Motor Walker Robot )
After some thinking, I realise that you don't need to cut the tap for the one motor walker.
If you want to build the one motor walker, I suggest you try the to build the robot without cutting the tap.If you want to make a rolling robot by using servo motors for the locomotion then cut the tap.
To cut the tap please read carefully.
I have already broken the entire gear by using a side cutter. I was sort of piss off!
I recommend you be carefull and use a hacksaw.
Take your time!
Put every thing back together and you have finish!
You can put some new grease it the gearbox if you want.