Designing Metal Cutting Tool Designs with Calculations

Contents

Table of contents

Introduction

1 Designing the first tool

Introduction to the Modular Finger Mill

1.1. Source Data:

1.2 Design Calculation

Heat treatment

1.3 Mill Fabrication Specification

2 Design of the second tool

Introduction to the Shaped Mill

2.1 Initial data:

2.2 Design calculation

Calculation of tolerance fields

Heat treatment

2.3 Mill Fabrication Specification

3 Designing the third tool

End Mill Calculation and Design

3.3 Calculation of tool unit for accuracy and compliance

Heat treatment

3.5 Mill Fabrication Specification

List of literature used

Introduction

The development of mechanical engineering is closely related to the improvement of the structures of technological machines and, first of all, metal cutting machines. Reliable and high-performance operation of the equipment is impossible without equipping it with the same reliable productive cutting tool and tooling. Being a "weak" link of any technological system, it is the tool that ensures its efficiency.

Cutting is one of the main methods of obtaining accurate machine parts. Considering that the requirements for the accuracy of machines and instruments increase, the prospect of developing machining processes becomes undisputed. Their versatility and flexibility provide them with advantages over other methods of manufacturing parts, especially in single and small-scale production.

Each cutting tool has a working and connecting part. The connecting part serves to connect the tool to the machine. It has basic surfaces with which the tool is oriented relative to the machine, and elements of force transfer from the machine to the tool. The working part separates the cut layer from the workpiece and removes the chips from the cutting zone. The optimal design of the working part of the cutting tool ensures high productivity and good processing quality.

Special guide parts may be provided to improve the accuracy of the machined surfaces and to ensure that they are positioned relative to each other.

The most important element of the structure of the working part is a cutting blade, which is a materialized space limited by surfaces, the intersection lines of which form cutting edges of the desired configuration.

The purpose of tool design is to create an optimal design for specific use conditions. The design tasks include the development of structural elements of the working, connecting and guiding parts, as well as technical requirements for them. It is possible to solve design problems by analogue design and synthesis.

1 Designing the first tool

Introduction to the Modular Finger Mill

The finger modular cutter is designed for cutting the shaped profile of the product. The profile of the cutter fully coincides with the profile of the cavity of the teeth of the spur-toothed involute wheel. Therefore, the calculation of the profile of these cutters is reduced to the determination of the profile of the tooth cavity of the spur wheel to be cut by these cutters .

Cutter profile is determined in the form of finding coordinates of profiling points for individual node points of profile of wheel teeth cavity defined by radii of arbitrarily selected circles.

1.3 Mill Fabrication Specification

During chemical-thermal processing, characteristic distortions in the shape of the parts occur, which are most difficult to correct by subsequent mechanical processing, which must be taken into account when designing: ovality of threaded holes, change in thread pitch and tooth size, longitudinal curvature, ellipse formation from a circular cross-tubular section, relative angular displacement of elements of complex figures.

In order to reduce these disadvantages, it is necessary that all surfaces of the cutter are absorbed and heat released as much as possible during the heat treatment. This is achieved if the following conditions are met :

1. The difference in mass and thickness of adjacent sections should be minimal, the transitions between them - smooth .

2. When designing a tool, you must ensure the same rigidity in all directions.

3. Mill elements requiring hardening must be structurally separated into a separate group.

4. Parts with hardened internal surfaces had gas discharge holes.

2 Design of the second tool

Introduction to the Shaped Mill

Shaped cutters are such cutters whose cutting edge or tooth profile has a shaped, complex outline. Shaped cutters are widely used in the industry in the external processing of various shaped profiles. They have a fairly simple design and manufacturing technology, they do not require special equipment during their operation.

2.3 Mill Fabrication Specification

During chemical-thermal processing, characteristic distortions in the shape of the parts occur, which are most difficult to correct by subsequent mechanical processing, which must be taken into account when designing: ovality of threaded holes, change in thread pitch and tooth size, longitudinal curvature, ellipse formation from a circular cross-tubular section, relative angular displacement of elements of complex figures.

In order to reduce these disadvantages, it is necessary that all surfaces of the cutter are absorbed and heat released as much as possible during the heat treatment. This is achieved if the following conditions are met :

1. The difference in mass and thickness of adjacent sections should be minimal, the transitions between them - smooth .

2. When designing a tool, you must ensure the same rigidity in all directions.

3. Mill elements requiring hardening must be structurally separated into a separate group.

4. Parts with hardened internal surfaces had gas discharge holes.

Roughness of profile and mounting hole Rz1.25; running out of support ends 0.02 mm; profile run-out 0.03 mm; beating of outer diameter 0.05 mm step error ± 10 μm; error of half angle of profile ±20َ.

3.5 Mill Fabrication Specification

During chemical-thermal processing, characteristic distortions in the shape of the parts occur, which are most difficult to correct by subsequent mechanical processing, which must be taken into account when designing: ovality of threaded holes, change in thread pitch and tooth size, longitudinal curvature, ellipse formation from a circular cross-tubular section, relative angular displacement of elements of complex figures.

In order to reduce these disadvantages, it is necessary that all surfaces of the cutter are absorbed and heat released as much as possible during the heat treatment. This is achieved if the following conditions are met :

1. The difference in mass and thickness of adjacent sections should be minimal, the transitions between them - smooth .

2. When designing a tool, you must ensure the same rigidity in all directions.

3. Mill elements requiring hardening must be structurally separated into a separate group.

4. Parts with hardened internal surfaces had gas discharge holes.

Roughness of profile and mounting hole Rz1.25; running out of support ends 0.02 mm; profile run-out 0.03 mm; beating of outer diameter 0.05 mm step error ± 10 μm; error of half angle of profile ±20َ.