4.3 Machines You May Encounter in a Shop Setting

Douglas Rupik, M.Ed., JIW

Common Shop Machines and their Functions

A well-equipped fabrication shop will likely have several metal working machines. Cutting, punching, and forming machines can make otherwise time and labor intensive tasks quick and easy. Machine shop tools include lathes and mills for subtractive manufacturing.

Cutting machines include cold cutting machines such as band saws, circular saws, power hacksaws, and shears. Thermal cutting equipment includes oxy-fuel torches, and plasma and laser cutting equipment. These may be manual or machine-operated.

Band saws may be dry or have a fluid coolant/lubricant system and may be oriented vertically or horizontally. Care must be taken when changing blades. Be sure to wear gloves, have another person to help, if needed, and be sure the teeth are oriented the correct way in relation to the material to be cut as well as in relation to the drive wheels. Some bandsaw wheels have a flange to keep the blade in place. The back of the blade should rest on this flange, not the teeth. Be sure all guards are in place, and the material being cut is secure. If the bandsaw is of the type requiring you to feed the piece in manually, be sure that you are not wearing gloves and that if you or the part slips, your hand, fingers, or other body parts will not end up in the blade. Don’t let your various body parts touch the blade. Keep the piece you are cutting flat against the tabletop as you feed it to the blade. If you are using a bandsaw that cuts a stationary, clamped piece, be sure it is secure and keeps your hands away from the blade when in use.

Circular saws for metal are usually large and cooled with fluid, and the workpiece is clamped. Be sure to keep your hands away from the blade while in use. Power hacksaws for metal are configured similarly to a horizontal bandsaw, but the blade is short and reciprocates rather than being a continuous band. Do not wear gloves or other clothing that may be caught in moving parts. Keep your hands well away from the blade while the machine is in use.

Shears are used for cutting sheet, plate, and flat bar. Shears usually have hold-down hammers that keep the material flat while the blade cuts. These hold-down hammers may exert enough force to completely crush fingers or hands. Some specialty shears are designed to cut shapes such as angle, channel, and round stock. Coper/notchers are special shears for cutting notches in flat, angle stock, coping pipe, and tubing. Do not place fingers in the area where the blade travels or in any pinch points created by the blade’s cutting action.

Thermal cutting equipment may be hand-held (covered in other chapters) or machine-operated, such as a track torch or CNC cutting table. When using oxy-fuel equipment, observe all applicable safety rules and wear appropriate PPE, such as eye protection. When using plasma or laser cutting equipment (or waterjet), be sure to follow all manufacturer’s operating and safety instructions. Be aware that high voltages and liquid coolants can create their own hazardous conditions, so use due caution.

Punching equipment is used to put holes in sections of metal. Older equipment may be powered by a flywheel/inertia, while newer equipment is hydraulic. Either style can seriously injure you when improperly used, but a hydraulic machine is often considered safer, as it may reverse itself mid-cycle when the actuating mechanism (foot pedal or hand buttons) is released, while a flywheel/inertia machine will cycle without stopping. When using this equipment, care must also be taken to ensure the punch and die are properly aligned, lest these break during use, creating a hazard due to flying bits and pieces.

Forming machines include presses, brakes, and rollers. This equipment is often used with sheet metal or plate to bend corners or roll to a radius. Care should be taken to keep hands and fingers clear of the moving parts of the machine and the material itself, as it will move as the machine bends and shapes it.

Presses use pressure to flatten, bend, or shape metal around forms to bring the metal to a desired shape. Brakes clamp sheet metal down and bend the metal to a desired angle. Rollers pinch metal between two rollers and feed it into a third roller that steadily bends the metal into a curved shape. Think of a wringer on an antique clothes washing machine or a paper shredder that pulls sheets of paper in. Avoid putting your fingers into this machine. It will flatten them.

Machine shops commonly have lathes, which spin pieces of metal while stationary blades cut it into various shapes. Milling machines hold the metal in place while spinning blades cut away metal to form various shapes. Either of these types of machines requires extensive training to safely use, and improper use can result in serious injury such as the amputation of limbs or even death.

Safe Use of Metal-Working Machines

Metal-working machines in a shop setting are typically heavy-duty and capable of exerting tons of force. These machines require thorough training for proper use. Proper use includes setup, cleaning, and basic routine maintenance. Insist on proper instruction from your employer, and do not rely on watching a co-worker from across the shop or random YouTube videos. As stated before, do not get creative when using power equipment.

Always wear appropriate PPE such as safety glasses and earplugs. When using equipment with spinning parts, such as a drill press, milling machine, or lathe, do not wear gloves, baggy sleeves, or loose, dangling hair, clothes, or jewelry. These may become entangled in the machine and draw you into it, resulting in serious injury and death. These machines often rotate at such fast speeds you will not even have time to react. When clearing chips or shavings from rotating equipment, do not use rags, use compressed air, and be mindful that the blown chips and shavings themselves may become hazardous projectiles.

Never use equipment that is damaged, always follow the manufacturer’s instructions on proper use.

Safe Use of Related Tools

Smaller shop tools such as drill presses, belt sanders, and bench grinders can present similar hazards to their larger counterparts, their primary hazards being entrapment in rotating parts, and throwing chips, shavings, or hot sparks at you. As always, receive proper training before using any piece of shop equipment, follow the manufacturer’s instructions, and never use damaged equipment.

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Introduction to Welding Copyright © by Douglas Rupik, M.Ed., JIW is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted.