Gear terminology formula. Power transmission Part 2.

Gear terminology formula This calculator provides the calculation of basic gear terminology for mechanical engineering applications. D. History of Gears P4 3. Pitch circle diameter. Simple Gear Trains •For a pinion 2 driving a gear 3, the speed of the driven gear is 16 Simple Gear Trains yFor a pinion 2 driving a gear 3, the speed of the driven gear is Shigley¶s Mechanical Engineering Design n 2 = & 2 n 3 = & 3 r 3 r 2 P N N 32 V P n 698 Mechanical Engineering Design Lead Angle !,Pressure Angle Addendum Dedendum deg!n A compound gear train is formed of eight gears. Spur gears in a 2-gear drive system (Gear #1 and Gear #2) will rotate in opposite directions. It is an imaginary circle drawn on gear profile in such a way that a pure rolling motion on this circle gives the motion which is exactly similar to the gear motion. In the previous article, I detailed the proper terminology for spur gearing. These terms are important for understanding how gears work and for designing and manufacturing gears. Pitch diameter: Diameter of the pitch circle. Having a good understanding of the formula allows for more accurate calculations and can help identify potential design issues early on in the process . Spiral bevel gears are an integral part of many mechanical systems, providing smooth and efficient power transmission. txt) or read online for free. The module is universally used worldwide to indicate the size of the gear, using the symbol m (module) and numbers (millimeters) to represent the size of the teeth. The reverted gear train gear ratio is calculated similarly to the compound gear train. Feb 20, 2022 · What are cone distances in bevel and hypoid gears? Find out in this preview for the Gears: Bevel and Hypoid Gear Terminology course from THORS eLearning Solu Apr 20, 2021 · The document discusses gears and their classification. Gears are often used to transmit power or motion from one shaft to another shaft when the shafts are located close to each other. Nov 19, 2014 · Spur Gear Terminology • Pressure angle-standard angle at which pressure from the tooth of one gear is passed to tooth of another-involute gears use 14 1/2° or 20° • Root diameter-diameter of the root circle. The document was prepared by a student as part of an assignment on spur gear terminology. R. Understanding each one is important to finding the number of teeth in a spur gear. When an intermediary gear set or idler gear is introduced between the two gears the drive gear (Gear #1) and the last gear (Gear #3) will rotate in the same direction. page. Pitch point. pdf - Free download as PDF File (. Pinion: The smaller-sized gear in any meshed pair. It is the only positive drive which can transfer exact velocity ratio to the driven shaft, that’s why it is widely used in various machines and other mechanical devices. 9 Right-handed Helical Gear (Important Gear Terminology and Gear Nomenclature in Fig 2. Example Calculation: Suppose we want to calculate the gear module for a gear with a pitch circle diameter of 50 mm and 20 teeth. Instead of being parallel Dec 26, 2024 · The Comprehensive Gear Design Master Class is a 17 part series of videos and text where you will learn: How to size gears so they mesh; Calculate the stress on the gear teeth; Calculate gear ratios in planetary system; After completing this course you will be able to correctly design and spec gear boxes for your applications the first time. (Important Gear Terminology and Gear Nomenclature in Fig 2. This video explains all the terms used to describe spur gear. Thetest for a huntingratio isthatthe numberof teethin the pinionand, separately,the numberof teethin the gear,cannot be dividedby thesame The geometry of a helical gear is directly dependent on the manufacturing tooling and processes used to make the gear. At the end of the article you can easily download whole document in PDF format. Follow me on:https://www. (The involute of a circle is the spiraling curve traced by the end of an imaginary taut string unwinding itself from that stationary circle. The circumference of the pitch circle (πd) is its diameter (pitch circle diameter = d) multiplied by the pi π. Key gear terminology includes: - Addendum: Distance from pitch circle to tooth tip - Dedendum: Distance from pitch circle to bottom of tooth space - Pitch circle: Imaginary circles used to define gear dimensions and motion There are several methods to measure gear tooth thickness indirectly, such as using a vernier calliper 1. Basic Gear Terminology and Calculation _ KHK Gears. 0-10 107% Rule Basic Gear Terminology INVOLUTE Face Width is the length of the teeth in the axial direction. Gear Accuracy and Strength P24 10. This video shows the common gear terminology Gear Definitions and Terminology. This article hopefully will broaden your knowledge of bevel gear terminology. 02inOctober,1948. tutorialspoint. The pitch circle is a circle on the face of a gear that passes through points that are radially half way up the working depth of the teeth. htmLecture By: Mr. 09=17（always round down）. It has parts similar to a spur gear except for one, which is called Throat Diameter as shown in Figure 8. wear each in the first gear will encounter each tooth of the second gear equally. Using the formula above would result in the following calculation: In this example the module of the gear is 2 mm, meaning every tooth of the gear would span 2 mm along the pitch Feb 17, 2024 · Popularity: ⭐⭐⭐ Gear Design Formulas This calculator provides the calculation of gear design formulas for determining the module, pitch diameter, and number of teeth of a gear. Basic Gear Terminology. Explanation. Gear Products and Suppliers | Gear Knowledge Menu. To understand the tooling and manufacturing processes used to make a helical gear, see the notebooks on gear tooling. For spiral bevel gears, one gear will have teeth with a left-hand spiral, and the mating gear will have teeth with a right-hand spiral. The gear teeth calculation formula uses a number of terms. Feb 23, 2019 · The document then covers gear nomenclature, defining various gear parts and measurements like pinion, gear, pitch circle, addendum, dedendum, clearance, face width, and pressure angle. Commonly Used Terminology • Gear Diameters o True Involute Form (TIF Jun 18, 2023 · Gear Terminology Reference Welcome to the Gear Terminology Reference! This comprehensive guide provides a glossary of gear-related terms, definitions, and explanations. When gear sets are visualized as a pair of smooth contacting #sscje #mechanical #gearinstitute Click here to download our apphttps://edumartin. This type of gear comes with two kinds of tooth profiles in accordance with the datum surface. If a gear is produced “A” style, then it does not have a hub. With a 20 deg. This 3D model shows visual nomenclature for: Whole Depth; Working Depth; Addendum; Dedendum; Tooth Thickness; Circular Pitch; Width of Space; Clearance; Dedendum Circle; Clearance Circle; Pitch Circle Helix; Addendum Circle; Face Width It is a Education platform run by Aditya Sharma. We can also derive the Reference Diameter (d), which is also known as the Pitch Diameter. The term used to indicate the size of a gear is called the module. It also classifies gears based on position of axes and peripheral velocity. It defines various gear terminology like circular pitch, pressure angle, addendum and dedendum. Dec 17, 2017 · Hello FriendsIn this video we are going to see all definitions used in gear terminology which includes pitch circle, Addendum circle, dedendum circle, circul Gears Classification of gears – Gear tooth terminology - Fundamental Law of toothed gearing and involute gearing – Length of path of contact and contact. P · COS Φ (Ro1 and Ro2 = Outside Radius of gear 1 and Gear 2) (Rb1 and Rb2 = Base Radius of Gear 1 and Gear 2) (C = Center Distance, P = Circular Pitch, Φ = Pressure Angle) Contact Ratio Total (mf) – is the ratio of the sum of the arc of action and the face advance to the circular pitch. 1 Spur Gear Design Calculator a When gears are preshave cut on a gear shaper the dedendum will usually need to be increased to 1. 6. Dec 29, 2023 · Explanation of Gear Terms 1. This model is ideal if you wish to show the names, terminology and definitions associated with a typical gear. The face width is the distance across the gear teeth, in the direc-tion perpendicular to the Reference Diameter. This is where the gear’s speed is measured. Jun 26, 2020 · This document provides definitions for common gear terminology used in gear design and calculation. ADDENDUM (a) is the height by which a tooth projects beyond the pitch circle or pitch line. Jan 14, 2023 · gear terminologygear Detailsgear modulepitch circle diameter of geargear all partsgear levelingaddendum lengthaddendum diameterdedendum lengthdedendum diamet Get access to the latest Gear Terminology: Part 1 (in Hindi) prepared with GATE - Iconic Pro course curated by Kapil Kumar on Unacademy to prepare for the toughest competitive exam. Gear Terminology is a page to learn gear related technical nomenclature for all machine designers. Jul 31, 2023 · A spur gear is a type of cylindrical gear with straight teeth that are cut parallel to the axis of rotation. You’ll be speaking the language of Formula 1 like a seasoned fan in no time. Reverted gear trains are a type of compound gear train in which input and output shafts are on the same axis. Explanation Terminology . It defines various gear types including spur gears, helical gears, bevel gears, worm gears, and rack gears. Types of Gears P14 7. 157 m where m is module. Root Diameter: The diameter of the circle at the base of the gear teeth. 5) Addendum Dedendum Root diameter Reference diameter Tip diameter The Addendum and dedendum circle introduced here are a reference circle that cannot be seen on a gear, as it is a virtual circle, determined by gear size. This is why understanding the spur gear calculation formula information is important. Explanation Calculation Example: Gear design formulas are used to determine the dimensions and properties of gears, which are essential components in power transmission systems. Let's Search for a Gear P2 2. Calculation Example: Gear terminology is a set of terms used to describe the geometry and dimensions of gears. Figure 3 Worm Gear Terminology Gear Terminology. ] In 1926 the AGMAadopted a recommended practice for gearing nomenclature,termsand definitions. (Figure 2. Whether you’re a beginner or an experienced professional, this reference is designed to cater to your needs. Shigley and C. _____Online learning is rapidly becoming one of t Sep 29, 2005 · 1012--G05, Gear Nomenclature, Definitions of Terms with Symbols. In this article, we will explore the Gear Design Equations and Formula | Circular Pitches and Equivalent Diametral Pitches Table; Gear Types and Application Data Table Chart - Engineers Edge ; Planetary Epicyclic Gear Ratios Equations and Calculators; Spur and related Gear Definitions and Terminology; Gear Terminology and Equations; Elements of Metric Gear Design; Helix Spur Type toothcont actsevery gear tooth before itcontactsany gear tooth a second time. It is an imaginary circle which by pure rolling action, would give the same motion as the actual gear. The Base Diameter (d b), is used in the manufacture of the gear. E. Gear terminology means all definitions used to describe a gear or the terms used to design a gear. Spur Gear Design Formulas 28 Sep 2024 Tags: Mechanical Engineering Machine Design Gear Manufacturing Processes Calculation Popularity: ⭐⭐⭐ Answer: c Explanation: Path of recess is the portion of the path of contact from the pitch point to the end of contact. ) In involute gear design, all contact between two gears occurs in the same fixed, flat plane Easy engineer app download here https://goo. Dudley ANSI/AGMA 2001-D04: Fundamental Rating Factors and Calculation Methods for Involute Spur and Helical Gear Teeth – Nov 13, 2024 · Gear Terminology. Gear Terminology . Pitch Diameter (P. involute gear, the profiles of the teeth are involutes of a circle. F Face gears Face width. And Pitch Diameter is calculated the same as for spur gears. Mar 6, 2021 · Gear terminology are the terms related to a gear that helps in the design of it and describes the shape and size of gear. Calculating the pitch circle diameter of a gear requires understanding basic gear terminology and applying the correct formula. Apr 18, 2020 · Gear Terminology with all important terms is well explained with line of action and pressure angle in English. Gear Terminology Watch More Videos at: https://www. The vocabularies for gear numerical formula and gear drawings are defined in JIS B 0121:1999 International gear no-tation - Symbols for geometrical data. Pitch Circle. About Gear Mates P10 5. com/videotutorials/index. Gear ratio: The number of revolutions a driving gear of gear train much makes, per revolution of the gear being driven. The most common definitions are described below. See Figure 2. By using the module, number of teeth, and addendum, you can calculate the PCD and determine the size and shape of the gear teeth. TEL : +81 48 254 1744 Gear Design Simplified by Franklin D. Pitch circle: The circle, the radius of which is equal to the distance from the center of the gear to the pitch point. gear terminology lecture,gear terminology explained,gear terminology ppt, gear terminology pdf, gear terminology video,gear terminology formula, Types of g Test your knowledge on essential gear terminology and calculations. Apr 7, 2018 · Here are some basic definitions used in gear terminology. Oct 3, 2024 · Calculation Formula. The size of the gear is usually specified by the pitch circle diameter. Spur Gear 1. The document defines various terms used in gear terminology and calculations. It is also known as pitch diameter. 5 – rsinφ; where r a is the radius of addendum of the smaller gear, r is the radius of the smaller gear and φ is the pressure angle between the two gears. Jones and Henry H. Helical gear The teeth cut on the periphery are of helical screw form A helical teeth is inclined at an angle to the axis. How to Make Gears P26 11. 2. In total, it defines over 20 specific gear terminology terms and concepts. link/jLFrJoin telegram channelhttps://t. Dedendum: The depth of a gear tooth below the pitch circle. What is the outside diameter Aug 9, 2024 · Conclusion. 9) Normal module; Transverse module; Helix angle β Equations Tooth Parts, 20-and 25-degree Involute Full-depth Teeth ANSI Coarse Pitch Spur Gear Tooth Forms ANSI B6. It defines key terms like module, which is the ratio of the pitch diameter to the number of teeth and appears in many gear calculation formulas. Er. For each term, it provides a brief definition and explanation of how it relates to gear design and Your queries:backlashroot clearanceroot clearance and backlash formulagear backlashbacklash in gears#root clearance and backlash#root clearance and backlash Dec 16, 2016 · This document provides definitions for common gear terminology used in gear design and calculation. It defines key terms like module, pitch, pressure angle, number of teeth, and diameter. Fig. Pitch rises, face width rises 2. This calculator provides the calculation of circular pitch and diametral pitch for gear terminology. instagram. It is the perfect destination for students, and engineers to learn, explore, and stay up to date on the latest trends. Gear terms: fundamental law of gearing velocity ratio circular pitch base pitch pitch diameters, pitch radii center distance addendum dedendum whole depth clearance outside diameter contact ratio backlash Gear Trains simple compound reverted Epicyclic Trains formula method tabular method The document introduces basic gear terminology and calculations. Fundamental Gear Terms P18 8. It is a basic dimension from which many other features of Jul 15, 2019 · As mentioned in that article, without a proper understanding of the terminology, you are at a great disadvantage. BASE DIAMETER (Db) is the diameter of the base cylinder from which the involute portion of a tooth profile is generated. This quiz covers important concepts such as whole depth, backlash, and tolerance, which are crucial for understanding gear design and function. This page is a part of KHK's Gear Technical Reference. be/hNc9EQThXxkPressure angle in relation to gear teeth, als gear face. Gears Are Ubiquitous P32 Hi! How are you? Oh, my name? Gear (wheel) – A gear (wheel) is a machine part with gear teeth. They are used to achieve a high gear ratio within a limited space. Gear Materials and Heat Treatment P22 9. Spur gears have straight teeth that run parallel to the shaft. In the above example, gear-1 and gear-3 are on the same axis. Dec 6, 2022 · Following are the gear terminology and gear terms used in the description of gears: Pitch Circle: A pitch circle (operating) is the curve of the intersection of a pitch surface of revolution and a Covering everything from DRS and G-force to oversteer, slipstreaming, tyre warmers, and turbulence, this guide offers clear explanations of the most frequently used F1 terms. m1, m3, m8… are known as module 1, module 3, module 8 respectively. Mischke Gear Handbook: The Design, Manufacture, and Application of Gears edited by Darle W. It covers gear terminology such as pressure angle and describes how parameters like pressure angle and center distance affect gear performance and interference. The fundamental term in metric gearing is the designation of pitch. Pitch rises, face width falls 3. Mar 21, 2019 · Outside diameter: The major diameter of the gear. Power transmission Part 2. . Spur Gear Definition: Spur Gear is the most used gears, having Straight teeth and are mounted on two or more parallel shafts. TEL : +81 48 254 1744 Nov 10, 2021 · The gear ratio is the ratio of the number of turns the output shaft makes when the input shaft turns once. Examples are given to demonstrate how to use the formulas Basic Of Gears -Gear Terminology/ Gear nomenclature Gears: Introduction: The slip and creep in the belt or rope drives is a common phenomenon, in the A Gear application is to transfer power from one shaft to another shaft at the same or different speeds. This notebook focuses on the resulting geometry of manufactured gears and gear pairs, not on how they are made. Pitch circle. pdf), Text File (. The terminology was established by the American Gear Manufacturers Association (AGMA), under accreditation from the American National Standards Institute (ANSI). ) is the diameter of the pitch circle. It provides formulas for calculating gear properties based on these terms, such as pitch from module, module from circular pitch, and reference diameter from number of teeth and module. A complete revision of terms and definitions by the AGMA Nomenclature Committee was issuedasAGMA112. Gear Ratio – The ratio of the larger to smaller number of teeth in mating gears. Where: m = gear module (mm or in) D = pitch circle diameter (mm or in) z = number of teeth. me/gearinstituteJE की Hello Everyone Welcome To Engineer's Academy Topics Covered : In this Video We have covered the Gear terminology , Various points We have seen in this Vid Mar 10, 2021 · Today we will study the Definition, Types, Terminology, Advantages, Disadvantages, and Application of Spur Gear. The basic formula for calculating gear module is as follows: As an example, consider a gear with a pitch diameter of 60mm, and 30 teeth. In other words, the Gear ratio is the ratio between the number of teeth on two gears that are meshed together, or two sprockets connected with a common roller chain, or the circumferences of two pulleys connected with a drive belt. Numerous dimensional parameters define the shape of the tooth profile, determine how the gears fit together, and identify locations where forces act at the gear teeth. Figure 2 WormGear icon of the Gear group in the Gear tab Terminology Worm Gear has a pitch diameter at the center point of the wrap-around curve. The majority of calculations for spur gears can be applied to helical gears too. What are Spur and Helical Gears? • Axis, Planes, and Helix o Axis of Rotation o Normal Plane o Transverse Plane o Helix o Lead o Helix Angle o Hand of Helix • Gear Geometry o Involute o Flank o Profile o Tooth Helix o Tooth Alignment o Gear Quality II. Calculation Examples Oct 19, 2024 · Gear Terminology Calculations in Mechanical Engineering 19 Oct 2024 Tags: Mechanical Engineering Machine Design Gears Basic Gear Terminology calculation. It also defines other important terms like reference diameter, center distance, and pressure angle. Popularity: ⭐⭐⭐. G Gear efficiency Gear formula Gear injection molding Gear shaper Gears with a pressure angle of 20 degrees Ground gears. Tip / Outside Diameter: The diameter of the circle that touches the outermost points of the gear teeth. May 12, 2021 · Along with spur gear terminology, we will also know about the spur gear formula which is related to the terminology of spur gear. Pich circle is the imaginary circle that rolls without slipping with a pitch circle of a mating gear. Hunting ratios tend to equalizetooth wearandimprovetooth spa cing. Spur Gear Terminology. 40/P to allow for the higher fillet trochoid produced by the shaper cutter. Perfect for mechanical engineering students and enthusiasts alike. H Hardened gears Hardness of gears Helical rack Helix angle of gears Mar 30, 2022 · gear cutting in lathe machine,gears,gear cutting,make gears,change gears,lathe gears,thread cutting in lathe machine,gear ratio,gear ratio calculation,gear r Aug 30, 2024 · Formula for Calculating Gear Module: The formula for calculating gear module is: m = D / z. The formula for this value is: z ∗ m. It included some symbols and abbreviations. Ryffel – Mechanical Engineering Design by J. This is a part of KHK's "Introduction to Gears". Standard value of clearance is 0. Spur Gear Formulas. Pressure angle gear if the gear has there are additional terms that apply when the gear set is produced as a spiral bevel gear set. In terms of automobiles, this means the number of revolutions the engine makes per revolution of the rear wheel. Apr 7, 2023 · A spur gear is one of the simplest and most common types of cylindrical gears. Understand the Key Terminology Used in the Gear Teeth Calculation Formula. आज हम इस पोस्ट में Gear terminology के बारे में चर्चा करेंगे। gear का उपयोग व्यापक रूप से यांत्रिक(mechanical) उद्योगों में power ट्रांसमिशन रूप में किया जाता है Aug 13, 2023 · 2. It lists 24 key terms including pitch circle, pitch diameter, pressure angle, pitch point, addendum, dedendum, circular pitch, diametral pitch, module, clearance, tooth thickness, face width, profile, and backlash. Examples : 21 and 41, 30 and 61, - prime, 21 and 39, 30 and 62, - not prime Minimum Number of Gear Teeth. 9) Fig. It is the diameter of the pitch circle. 1. Example Calculation Feb 18, 2025 · Updated on February 18th, 2025. Formulas for gear design including center distance and diametral pitch are provided. com/nileshku Dec 4, 2012 · This document provides definitions for common gear terminology used in gear design and calculation. Oct 31, 2024 · How to calculate gear module. Common gear materials are also outlined. This page lists the standard US nomenclature used in the description of mechanical gear construction and function, together with definitions of the terms. gl/TpXaS7classification of gear in hindihttps://youtu. The design of spur gear is 1. Learn its terminology, types, advantages & applications Jun 28, 2020 · Path of Contact & Arc of Contact in meshing Gears are briefly discuss in this video. 3. This calculator provides the calculation of various gear terminology used in gear design. Helical Gears – Helical gear sets run on non-intersecting, parallel shafts. Calculation Example: The circular pitch and diametral pitch are two important parameters used to describe Gear terminology in Hindi. Variation of tooth thickness: Difference between the larges and the smallest tooth thickness of a gear. Dec 16, 2016 · This document provides definitions for common gear terminology used in gear design and calculation. ) is the diameter of a circle around the outer surface, or tops of the gear teeth. Pitch falls, face width rises 4. E End relief (Relieving) Enveloping worm gears External gear. The length through the bore (LTB) is the total width of the gear and is used to confirm that the face width and the hub projection Accurate spur gear calculations are essential for the successful design and operation of machinery. Table of Contents Introduction Gear Types Tooth Profiles Gear Manufacturing Methods Terminology Used in Design and 1. Follow me o Gear Types and Terminology is a page to learn types of gears and gear related technical words. This angle is most commonly set to 35 degrees. Using the formula above, we get: • Gear Types I. As we proceed from the pinion on the electric motor to the gear on the output shaft, how do the pitch and face width vary? 1. This article covers gear terminology or basic terms used in gears and gear calculations. Pitch falls, face width falls Oct 6, 2024 · Tags: Calculations Mathematics Maths behind the topic gear terminology. Gears as a Machine Element P8 4. It is the point where the two pitch circle of the mating gears touch each other. Sep 28, 2024 · Popularity: ⭐⭐⭐. The document discusses gears and gear trains. The gear module is calculated using the formula: \[ \text{Module} = \frac{\text{Gear Diameter (mm)}}{\text{Number of Teeth}} \] This formula provides a straightforward method to determine the size of the gear teeth, which is essential for the gear's function and performance. 6 Illustration of Center to Center Distance of Gears in Mesh Oct 19, 2024 · Gear Terminology Calculation. The geometry of a simple spur gear tooth is complex. It has a formula of: d ∗ (cos α) The pitch circle of a gear corresponds to the outer circumference of the friction wheel (gears can be thought of as friction wheels with teeth attached) and is the reference circle for determining the pitch of the gear teeth. Himanshu Vasishta, Tutorials Point India Pr Driven gear Driving gear Dedendum of gears Double helical gears. It is given by the formula (r a 2 – r 2 cos 2 φ) 0. What is an addendum and dedendum? An addendum is the radial distance between the pitch circle and the addendum circle whereas the distance from the pitch circle to the dedendum circle is the dedendum. Addendum: The height of a gear tooth above the pitch circle. The gear tooth is a component of a mechanical power transmission system that does not lack for descriptive terminology. These gears are Apr 15, 2019 · From these values, we can determine the Center Distance (a), as it is derived from the formula: (z 1 + z 2) ∗ m /2. 4 Terminology of each part of the gear Terminologies of gears are defined in JIS B 0102:1999 Vocabulary of gear terms-Related to geometry. This is achieved when the highest common factor is unity or when the numbers are prime to each other. May 11, 2015 · Gears are used to transmit power or motion between two shafts. Pitch Circle Diameter (PCD) The pitch circle is an imaginary circle where two gears in mesh roll against each other. These gears have a curved tooth that is set at a specific spiral angle. We suggest you also read this article on types of gears and their applications. These formulas involve the Explanation: Term clearance used in terminology of gear tooth is the radial distance from the tooth top to the bottom of a mating tooth space when the teeth are engaged symmetrically. Outside Diameter (O. Gear Terminology Calculations. The Role of Gears P12 6. Aug 25, 2019 · Gear Terminology: Gear Module, Pitch Circle, Pitch circle diameter, Pressure angle, angle of obliquity, Addendum, Dedendum, Backlash If the teeth are not machined by tooth cutters, and the teeth profiles are still kept intact, then the 2 gears will get jammed in transmission. Of two gears that run together, the one with the larger number of teeth is called the gear. Basic Gear Terminology and Calculation _ KHK Gears - Free download as PDF File (. The formula for calculating the minimum teeth number without undercutting is:z min =2ha*/sin 2 αWhen ha*=1, and α=20°，we will have the z min =2*1/(sin20°） 2 =17. So for understanding these two term watch this video till end. szne nxlf asca olxuog arby incohb cesw egkgsv cedbx aowis qpu umdq mcsfffc iqujm tuzn