This is a quick and easy walkthrough on how to modify a HiTec Servo and make it a normal dc motor with gears.
To see how you can control your motors with the Arduino visit this instructable
1. Say hello to your servo, and say goodbye as well because what we are going to do here is irreversible.
We will hack essencial parts of the servo and it won�t be a servo anymore, it will be a powerfull dc motor with gears.
2. This are the tools we need, I think I don't need to describe them :)
3. Ok let's begin.
Start by removing the screw on the top.
4. Remove the four little screws on the back of the case.
5. Open the case.
6. And remove the top carefully.
7. We can see the gears inside the case. We only need to remove the first two gears, no need to remove the others.
Be careful enough and avoid contaminate the grease that surrounds the gears.
8. Remove the black and white gears.
9. Now it's time to remove the circuit on the bottom of the case, see the next foto.
10. Use the soldering iron and gently remove the circuit.
11. You can see now the dc motor.
12. Cut the wires that connect the potenciometer to the circuit.
13. Now remove the little screw inside the case.
14. Press the potenciometer thingey to remove it.
15. Parts we don't need anymore.. I wasn't carefull enough and broke the circuit.. no problem, we won't need it anymore, at least I don't know what I can do with it... :)
16. Now grab two wires with +- 15 cm, depends on your needs.
17. Grab your soldering iron and solder the wires to the motor pins. Note the red mark on the motor.
18. Now we are going to remove the thingey that tells to the servo to spin only 180º.
19. Remove the white ring.
20. Make an horizontal cut.
21. Then make a vertical cut.
22. The thingey is removed.
23. Remove any imperfections you see.