# Rack and Pinion Tooth Design

Discussion in 'Mechanical | Automobile | Aeronautics' started by smhale, Nov 27, 2011.

1. ### smhale Newbie

Engineering Discipline:
Mechanical
Hey everyone, I found this forum while trying to do some research on rack and pinion tooth design. I'm having trouble getting my teeth to match up and I'm hoping I can get some help. My only concern at the moment is making the teeth match so that I can create a 3D model. I was attempting to get dimensions for the addendum and dedendum as well as the tooth thickness based on my pitch circle radius (1 inch), a certain number of teeth (arbitrary for now) and a pressure angle of 20 degrees. If someone could please help me out with finding formulas for my tooth geometry based on the dimensions I have, I would really appreciate it. Also, if you are aware of any useful resources that may help me out, please send them my way.

Thanks.

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2. ### smhale Newbie

Engineering Discipline:
Mechanical
I should mention that the formulas I tried to use are as follows:

Number of Teeth = N
Pitch Diameter = d
Diametral Pitch = Pd = N/d
Dedendum = 1.25/Pd
Tooth Thickness = 1.571/Pd

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3. ### rebellionofrebel Apprentice

Engineering Discipline:
Mechanical
Refer to any standard Machine Design book like R norton or the one by Shigley.. U will get what u r looking for. Also try out AGMA handbooks or standard Design Data books they have all requisite formulae to guide you through. a thoeretical treatise will only be found in the books i had mentioned with authors or the AGMA handbooks

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4. ### A.V.Ramani Guru

Engineering Discipline:
Biomedical
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5. ### smhale Newbie

Engineering Discipline:
Mechanical
Thanks for the replies guys. I actually need exact physical dimensions to create a virtual model but that template will certainly help when I attempt to create a physical mockup. The formulas I have were taken from R Norton's Design of Machinery. He does not give much detail into the formulas and I am wondering if these will work for a rack and pinion. Norton called them "standard depth gear tooth deign" formulas. I assume they are true for any type of gear.

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6. ### A.V.Ramani Guru

Engineering Discipline:
Biomedical
Why are you cutting and pasting the response by rebellionofrebel? Serves no purpose and is a disservice to the person taking time to make a helpful reply.

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7. ### A.V.Ramani Guru

Engineering Discipline:
Biomedical
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