DIY spur gear making for change gear part 3

Making the gear.

1. prepare the tool
first i prepare tool what i called it semi hobing gear cutting tool

2. Mount dividing head to the table of milling machine and mount the MT3 mandrel to the center hole dividing head, the clam work piece to mandrel

3. Mount the tool to the collet arbor, these arbor is NT40

4. Setting center of tool using dead center of the tailstock.

5. setting zero point off tool to workpiece and cut it with depth of cut every 0.5 mm until 3 mm.

6. then finish the depth to 3.25 mm. you can calculate depth with height of gear formula. for modul 1.5mm it can be height of gear 3.25 mm.

7. with same depth, rotate the crank 20 hole at the sum of hole 30 or 44 hole at 66 sum of hole to make 60T of gear. you can calculate it by dividing equation of dividing head

Nc = i / z

Nc = Rotation of Crank
i = according to dividing head worm ratio = 40
z = number of teeth

8. repeat step no 7 every cutting until 60 teeth

9. after finish the gear unmount it from mandrel an debuur for clean the chip and sharp edge with file.

And now i can connecting X Axis to the dividing head to make a helical gear with change gear