Lathe Honor

Vocational Activities

Requirements

1. Define what a lathe is?

   Answer: A lathe is a machine tool that makes the workpiece ROTATE around an axis while a fixed cutting tool removes material, giving shape to the part (usually cylindrical). It is one of the most important machines in mechanics and metallurgy. — On the lathe, the workpiece rotates and the tool cuts — this is how cylindrical parts are shaped with precision.

2. What is the objective and purpose of a lathe?

   Answer: The objective of the lathe is to machine (shape) parts, removing material with precision to manufacture or repair components — such as shafts, screws, pins, pulleys and threads. The purpose is to produce cylindrical and symmetrical parts with exact measurements. — The lathe is used to manufacture and adjust parts with precise measurements — the basis of the mechanical industry.

3. What is the turning operation? Explain its working process.

   Answer: Turning is the machining operation in which the part rotates fixed to the lathe and a cutting tool advances against it, removing material in the form of chips, until the desired diameter, length and shape are obtained. — Turning is shaping the part by rotating it against the cutting tool — the central operation of the lathe.

4. What are the main fundamental operations that can be performed on a lathe?

   Answer: The main operations: cylindrical turning (external and internal), facing (truing the face/end), grooving/cutting, drilling (in the center), threading (making threads), knurling (creating texture) and conical turning. Each one gives a different shape to the part. — Facing, turning, drilling, threading and grooving — the lathe performs various operations to shape the part completely.

5. What materials are used in the manufacture of the tools used on the lathe? Give examples of tools made with these materials.

   Answer: Cutting tools are made of very hard materials resistant to heat: high-speed steel (HSS) — for common bits; carbide (tungsten carbide) — inserts for heavier and faster cuts; and ceramic and diamond/CBN — for high-precision machining and very hard materials. — High-speed steel and carbide are the most used materials in tools — hard enough to cut the metal of the part.

6. Identify and demonstrate, through drawings or photos, what the basic components of a lathe are?
7. Cite some accessories (parts) that make up the lathe and the function of each of them.

   Answer: • Chuck (with jaws): holds and centers the part. • Tailstock: supports the other end of the part. • Steady rest: supports long and thin parts. • Tool holder (post): holds the cutting tool. • Carriages (longitudinal and cross): move the tool. • Drill chuck: holds drill bits for drilling. — Each accessory holds, supports, or moves the workpiece and the tool — together they ensure the precision of the turning.

8. Identify at least 2 tools that can be used to measure parts made on the lathe. Explain the functionality of each of them.

   Answer: • Caliper: measures lengths, diameters (external and internal), and depths with good precision (tenths of a millimeter). • Micrometer: measures with even greater precision (hundredths of a millimeter), ideal for exact diameters and thicknesses. (Also the dial indicator.) — The caliper and the micrometer measure the workpiece with precision — without them, there is no way to ensure the exact measurement.

9. Describe the function of each of the following lathes listed below:
   • CNC lathe
   • Turret lathe
   • Vertical lathe
   • Universal horizontal lathe
   • Facing lathe
   • Copying lathe

   Answer: 1) CNC lathe: a lathe controlled by computer (Computer Numerical Control), which produces parts automatically, precisely and repeatably, ideal for mass production and complex geometries. 2) Turret lathe: has a rotating turret that holds several tools mounted at the same time, allowing quick switching of operations without repositioning the part, which speeds up repetitive production. 3) Vertical lathe: has the spindle in a vertical position and the chuck horizontal, being suitable for machining large, heavy and large-diameter parts, which gravity helps to keep seated. 4) Universal horizontal lathe: it is the most common and versatile type, with a horizontal spindle, used for general work such as turning, facing, threading and drilling on various parts. 5) Facing lathe: designed to machine parts of large diameter and small thickness (disks, flanges, pulleys), with an emphasis on facing operations. 6) Copying lathe: reproduces parts in series from a model or template, automatically copying the profile to obtain identical parts. — Each lathe serves a need — from the versatile universal one to the automatic CNC and the copying lathe that reproduces models.

10. Explain what an Industrial Technical Drawing is. How do you interpret it in an objective and easy-to-understand way?

    Answer: Industrial Technical Drawing is the graphic representation of a part or project, according to standards (ABNT/ISO), showing its shapes, views (front, top, side), dimensions, scales, and tolerances. It is interpreted by reading the views (the part from various angles), the dimensions (measurements), the scale, and the symbols — this is how you understand exactly how to manufacture the part. — Technical drawing is the 'language' of industry: reading views, dimensions, and symbols means understanding exactly what and how to manufacture.

11. What precautions should we take when handling a lathe? What personal protective equipment (PPE) can be used?

    Answer: Precautions: wear fitted clothing (never loose), tie back your hair, do not wear rings, chains, or gloves (they can be pulled in by the spinning part); keep the area clean; never measure or touch the part with the lathe running; and remove the chips with a brush or hook, not with your hand. PPE: safety glasses, closed-toe footwear, ear protection, and an apron — never gloves near the rotating part. — On the lathe, loose clothing and hair are a deadly danger — attention, PPE, and never touching the spinning part are the golden rules.

12. What is the influence of cutting speed, feed and depth of cut on the life of a tool?

    Answer: The greater the cutting speed, the feed, and the depth of cut, the faster the work — but the greater the heat and wear, reducing the SERVICE LIFE of the tool (which dulls or breaks sooner). Moderate values appropriate to the material prolong the tool and give a better finish. It is necessary to balance productivity and durability. — Cutting too fast heats up and wears out the tool; properly adjusting speed, feed, and depth makes the tool last longer.

13. With the help of a technician or specialist in the lathe field, make any cylindrical part, in view of the learning obtained in the basic lathe operations. Write a report of at least 300 words describing how this part was developed.