My 4th Axis Version

When i build my first CNC milling machine, It was in my to-do list to make a 4th axis for it... But i was having no idea how i will generate the G-code for it and what hardware i use to make it!!!.. I dont want to spent so much on it too..... I had two options, to make it belt-driven or gears driven... I decided to make it simple as i can.. and the best option was to make it belt-driven... i need one belt, two timing pullys, one shaft and a wood holding chuck and a tail-stock... Now to make it more DIY i decided to make the tail stock and wood holding chuck myself..and all the mounting from MDF... I never afraid of failure, and i think if one afraid of failure he can never get succeeded... You can see i first made the chuck from a pipe and plate with 4-jack screws for holding workpiece..but later i changed my this version of chuck and made it more simple...To remove the slack from the belt, i added idler pully... I used 200Oz-in Motor and later you will see what i created from this simple and low-cost arrangement...