I am trying to see what type of gears are utlizied in my 7"x36' old Clausing.

Took off and cleaned a 75 Teeth on the shaft to the QC gearbox and cannot figure out the DP the use. The OD of the gear is 122.2 mm and 75 teeth.

I looked at the Machinery's Handbook 11 edition (1930, $5 in garage sale) and by working backward reading page 619 of : Standard Full-depth Teeth I get the following:

Assume DP of 14;16;17;18 and using OD= (Number of teeth + 2) / Circular Pitch I get an approximate value for OD of the gear of:

DP CP (") OD of gear

___ ________ ___________

14 0.2224 ((75+2)*0.2224")/3.1416 = 138.5 mm (note that I mislead the issue a little bit because I converted the 0.2224 inches to mm while doing the formula

16. 0.1963. ((75+2)*0.1963")/3.1416 = 122.3 mm **********************

17 0.1848 ((75+2)*0.1846")/3.1416 = 124.9 mm

18 0.1745 ((75+2)*0.1745")/3.1416.= 114.9 mm

I guess I could assume that the DP of these gears is 16 and then proceed with that to calculate the other two gears I will be for metric conversion.

Can someone confirm my assumption?

Thanks.

Took off and cleaned a 75 Teeth on the shaft to the QC gearbox and cannot figure out the DP the use. The OD of the gear is 122.2 mm and 75 teeth.

I looked at the Machinery's Handbook 11 edition (1930, $5 in garage sale) and by working backward reading page 619 of : Standard Full-depth Teeth I get the following:

Assume DP of 14;16;17;18 and using OD= (Number of teeth + 2) / Circular Pitch I get an approximate value for OD of the gear of:

DP CP (") OD of gear

___ ________ ___________

14 0.2224 ((75+2)*0.2224")/3.1416 = 138.5 mm (note that I mislead the issue a little bit because I converted the 0.2224 inches to mm while doing the formula

16. 0.1963. ((75+2)*0.1963")/3.1416 = 122.3 mm **********************

17 0.1848 ((75+2)*0.1846")/3.1416 = 124.9 mm

18 0.1745 ((75+2)*0.1745")/3.1416.= 114.9 mm

I guess I could assume that the DP of these gears is 16 and then proceed with that to calculate the other two gears I will be for metric conversion.

Can someone confirm my assumption?

Thanks.

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