Seeking assistance with gear cutting

[autopilot]

I would like to cut approximately 50 each of the following gears: 12mm w 12 teeth, 20mm w 20 teeth, 30mm w 30 teeth and 40mm w 40 teeth. All will be 5mm thick, made of brass. Each size will need to mesh with all others. Picture attached is an example in plastic.

I have a mill and dividing head and general knowledge of how to do this. However, I could use assistance with 2 questions. 1) should I cut each gear individually at the final thickness or cut a wide gear, then cut each one to size? 2) what gear cutter or cutters do I need to accomplish this? Thanks in advance!

 

[autopilot]

I just looked closely at the plastic gear picture. They are not what I need. The brass gear below is the tooth profile I need.

 

[Cogsy]

As long as the dimensions you are quoting are PCD dimensions then you're looking at Mod 1 gears so you need Mod 1 cutters. For the sizes you need to cut you will need cutters 8, 6, 4 & 3 in Mod 1 (might make sense to buy a set and then you'd have the full range capability). It's up to you if you want to cut teeth on a wide blank and then trim gears off it or cut teeth on a correctly sized blank. Generally I go for a wide blank so I can make a few gears at once, but you do have to clean up the burrs from parting off once you slice them apart.