Gear Cutting Problem

[Alan CharlestonParticipant @alancharleston78882]

Hi,

Thanks for all the useful comments. Although my original question was for gears S and T, the first problem in the train was for gears G and H (19T & 41T) which added up to 60 teeth but needed to be 61 to tie in with gears E & F. I got around this by making gear H 42 teeth. I decided to remake these two gears because they were smaller than gears S & T. The module change required was 1.00 to 1.0167 which is larger than the 1.008 required to fix the problem with gears S & T. This, together with the fact that tooth form is more important for gears with fewer teeth, meant that if my fix worked for these gears, it should work for the larger gears further down the train.

The gears were cut using a module 1.00 gear cutter. The outside diameters of the blanks were 21 x 1.0167 = 21.35mm for the 19T gear, and 43 x 1.0167 = 43.72mm for the 41T gear. The depth of cut was 2.25 x 1.0167 = 2.29mm for both gears. I put the gears onto my depthing tool and found they meshed very well and rotated freely with no rough spots. The distance between their centrelines was 30.42mm which was close to the 30.5mm I was after.

Thanks again for all the comments.

Regards,

Alan C.

[Author]

Posts