Total NEWB here with 2 questions and I hope I'm in the right place.
While this isn't necessarily a cnc related question, I plan to use a cnc mill for the project.
I understand that the only way to make "correct" bevel gears is with a special (gleason?) shaping type machine because of the way the teeth on a bevel gear converge in the center of the cone. What I don't quite get is if I were to use an involute cutter or even a bevel cutter for both gears in a 90 degree bevel, would it matter that the profile isn't a true bevel tooth profile? I'm not planning on mating a made gear with a true bevel gear, I'm talking about making the pinion and gear the same way. Wouldn't they mesh fine since they both have the same tooth profile along the face? These aren't going to be high speed/high load gears, they're for a model. The motor output is 10,000 rpm, however it's geared down through a 50:1 gearbox and the motor will be in no way run up to it's full potential. So actual working rpms would be more in the 20rpm range.
The next question is with what the recommendation would be for the best fixture to approach the task with. I've seen videos/photos of people who have cut gears using a lathe and a vise mounted on the toolpost with an indexer on it, so I think anything is possible, but is a dividing head the absolute "must go" route? Could I get away with a rotary table w/ a 4 jaw? How about a "spindex"? I think I saw a video a while back of someone who wrote a program to run the 4th axis rotary table to cut gears (not bevel) and that would be a bit of a luxury.
I'm really looking for what would be an appropriate tooling setup to use to cut some small (I mean micro), somewhat accurate bevel gears using a little sherline mill. The gears I want to make would be brass and the OD of the gear is only 6mm! Probably .35mod/72dp. I'm Crazy right? lol
I have other uses for a 4th axis so I'm interested to see if anyone thinks that will work. As this is hobby stuff, I'm looking at the shars dividing head or the sherline rotary table. Many thanks for any advice/opinions.
Phil
While this isn't necessarily a cnc related question, I plan to use a cnc mill for the project.
I understand that the only way to make "correct" bevel gears is with a special (gleason?) shaping type machine because of the way the teeth on a bevel gear converge in the center of the cone. What I don't quite get is if I were to use an involute cutter or even a bevel cutter for both gears in a 90 degree bevel, would it matter that the profile isn't a true bevel tooth profile? I'm not planning on mating a made gear with a true bevel gear, I'm talking about making the pinion and gear the same way. Wouldn't they mesh fine since they both have the same tooth profile along the face? These aren't going to be high speed/high load gears, they're for a model. The motor output is 10,000 rpm, however it's geared down through a 50:1 gearbox and the motor will be in no way run up to it's full potential. So actual working rpms would be more in the 20rpm range.
The next question is with what the recommendation would be for the best fixture to approach the task with. I've seen videos/photos of people who have cut gears using a lathe and a vise mounted on the toolpost with an indexer on it, so I think anything is possible, but is a dividing head the absolute "must go" route? Could I get away with a rotary table w/ a 4 jaw? How about a "spindex"? I think I saw a video a while back of someone who wrote a program to run the 4th axis rotary table to cut gears (not bevel) and that would be a bit of a luxury.
I'm really looking for what would be an appropriate tooling setup to use to cut some small (I mean micro), somewhat accurate bevel gears using a little sherline mill. The gears I want to make would be brass and the OD of the gear is only 6mm! Probably .35mod/72dp. I'm Crazy right? lol
I have other uses for a 4th axis so I'm interested to see if anyone thinks that will work. As this is hobby stuff, I'm looking at the shars dividing head or the sherline rotary table. Many thanks for any advice/opinions.
Phil