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Guidelines

Shop Safety Primer
A Guide to safety in the shop, including how to work with power tools, materials, and safety equipment.

READING THIS DOCUMENT IS NOT A SUBSTITUTE FOR TAKING A SHOP SAFETY SEMINAR

Basics:

Master Power Switch:
There is a big red button near the grey circuit-breaker box mounted to the exposed-brick wall of the shop (the north wall). It turns off all the power to the shop tools. Make sure that you know exactly where it is. If you think there is an emergency situation under way, or that there is the immediate risk of an emergency situation, DO NOT HESITATE TO PRESS THE BUTTON. If you are not near the button, power off your tool immediately and provide appropriate assistance.

No Obligations:

You are never required to use the tools. Really. No core class at ITP requires their use. You can get an “A” in every core class without ever stepping foot into the power tool shop. If you’re scared to use a tool, don’t use it.Tools can be more dangerous when the operator handles the tool improperly due to apprehension.

State of Mind:
You are strictly forbidden from using a power tool if your alertness has been compromised for any reason. Some example reasons for compromised alertness:

  • Sleepiness / lack of sleep
  • Prescription medication
  • Consumption of alcohol
  • Use of illicit drugs or substances
  • Extreme Stress

Just don’t use the tools if you’re not feeling alert. It’s not worth it. Do your work the next day.

Preparations:
Put your safety goggles on.

Before you use any tool, secure all loose things that are attached to you. These may include hair, jewelry, and loose-fitting clothing. It is easy to get pulled into the strong rotational force of the power tools’ cutting apparatuses.

Now that your long hair is tied back, put your safety goggles back on.

Don’t wear gloves, they prevent you from being able to feel what’s going on with the tool. The exception to this is the metal bender. Always wear gloves when working with sharp-edged metal.

Consider also using hearing protection. Some of the tools can be quite loud. Damage to your hearing is cumulative, and might not exhibit symptoms for 10 years or so. By the time you start to notice, it could be way too late. If it’s loud enough to make you cringe, wear sound-dampening ear muffs or earplugs.

Make sure that the tool you are using is in proper working order. If you suspect that it might be under repair, or in need of repair, don’t try it out just to make sure. Contact a staff member, and inquire about the tool’s state of readiness.

If a drill bit, or saw blade is noticeably discolored (sometimes they turn blue with wear) or otherwise damaged. Don’t use it. If you notice that a tool is broken (even if it breaks while you are using it) contact a staff member immediately.

Make sure that the path around you is clear. It is important that people do not bump into each other, or trip on something or slip on sawdust. Be aware of the people around you, make sure that when you move a long piece of wood, that it’s not going to hit anyone. Make sure that the people around you are wearing their goggles before you begin to cut. Make sure that when you back away from the tool you are working on, that no one is behind you.

When you use a tool make sure the environment directly around you is clean and comfortable. A cluttered, or inconvenient work area can be dangerous. Clean up, and organize things before you begin. Your work will go more quickly, smoothly and safely. It’s worth 30 seconds of vacuuming, and 30 seconds of re-arranging.

Make sure that you are personally comfortable. Be aware of the way you are standing. Do you have good leverage on the tool? Are you able to reach the controls comfortably?

Before you turn on a tool, make sure you know what path the moving parts will make. Do a dry-run, without the tool powered on. This way you can ensure that your hands are not in the path of the cutting surface., and that your arms won’t have to cross each other and so forth. This can be especially important for those who are left handed, as tools are often designed with right-handed people in mind. Sometimes it is helpful to use a piece of wood with a notch in it to help you hold your subject in place – like a stilt for you hands.

Be sure that you know which direction the rotating parts of a tool will begin to rotate in when they are powered up. The cutting surfaces will tend to pull the subject being worked on in the direction of their rotation. This is extremely important when you are determining the best way to hold, or secure the subject.

Be prepared for the tool to kick. Due to the laws of momentum and inertia, a power tool will usually exert some kind of kinetic force on the user. These kicks or jolts usually occurs when the tool is first powered on, and when the tools cutting surface first comes into contact with the subject that is being worked on. Be prepared for this, and make sure that you don’t flinch or let go of the tool when this happens.

Never turn a tool on while its cutting surface is touching the subject that you are about to cut. The tools need a second of free-rotation in order to get up to the proper speed. Turning on a tool while its in contact with the subject can cause the tool to jam, or bind or kick very hard.

While you are using a tool, be aware of the sounds that it is making. If you hear an unusual change in pitch, a clunking noise, or a grinding noise for example, stop using it immediately. The sound that a tool produces can be a good indicator of the tool’s health. An unusual sound can indicate an unhealthy tool. An unhealthy tool can be dangerous.

If a tool breaks while you are using it, tell a staff member! Don’t leave it for the next person. A dysfunctional tool can be dangerous. Tools break sometimes. You will not be punished just because it happened to break while you were using it.

When you are finished using a tool, clean up. Put all the hand tools and clamps away, and clear wood or metal shavings away. Always leave the area that you were working in as clean, or cleaner than when you began.

Materials:

Wood:
Make sure it’s clear of nails and staples, and watch out for knots. You can use any of the tools on wood except the grinder or the shear/brake/roll machine. Never place a piece of wood on the wood pile if it is not clean. This applies even if you originally got the piece from the pile. Don’t just put it back. Either clean it, or throw it away.

Metal:
The only bench tools that can be used for metal are the grinder and the drill presses. When you drill metal, put a couple drops of cutting oil on the spot that you’re going to drill. Also, use a chassis punch to make a dimple in the material before you drill. This will prevent the drill bit from slipping from the point where you want the hole.

Plastic:
Plastic can be cut on the band saw, and with the drill presses. Other than that, you shouldn’t use any of the other bench tools for plastic. The one exception to this is that you can cut PVC tubing with the Miter Saw.

Specific Tools:

Drill Presses:

The drill press is designed to drill through relatively thin pieces of material. (If your drilling though metal, it should be especially thin.)

The part of the drill that holds the cutting tool (called the drill bit) is called the chuck. The chuck has teeth that bite down on the bit in order to hold it in place. The teeth are tightened and loosened by hand using a small gear with a handle on it, known as the chuck key. Ideally, the chuck key will be tethered to the drill press. If it’s not, make sure that you place it next to the drill when you’re finished with the tool. Don’t walk off with it.

When you tighten the chuck onto the bit, make sure the bit goes in straight and that it is well tightened. Especially with smaller diameter bits, it is possible for the teeth to grip the bit unevenly. This will cause the bit to protrude from the chuck off-center. You can double check a bit’s alignment by standing back, and briefly running the drill – allowing it to spin freely. This will clearly reveal whether the bit is in properly, as it will wobble if it’s not in correctly. If the chuck is not tight enough, the bit may get stuck on the material it is cutting, and slip inside the chuck. If this happens, turn off the drill.

The platform’s height is adjustable. Adjust its height making sure that the drill bit that you are using will go all the way through the material.

Make sure to clamp your material to the platform. For smaller pieces, you may need to use the drill press vice.

Make sure you are aware of the springiness of the handle on the drill press. Don’t just let go of it, allowing it to snap back into place.

If you’re drilling through metal, make sure to use cutting oil.

You should consider buying some drill bits for your own personal use. This will ensure that you have the right sizes on hand.

Miter Saw:
Also sometimes called a chop saw, this tool is used to cut narrow pieces at angles between 90° and 45°. It can be used to easily make mitered corners – corners where two 45° angles meet.

Before you cut, make sure that you are able to hold the subject so that it is steady, and in a way that your hands are nowhere near the cutting path. For long pieces, you may need to use clamps for stability. If someone helps you hold the material, make sure that they are also wearing goggles.

The blade is covered by a plastic guard. DO NOT LIFT THE GUARD MANUALLY! The guard will be lifted automatically as you cut.

Before, you cut, make sure that your cutting stroke will make your cut completely. If the subject is too large, use a different tool. When you cut, make sure to complete your cutting stroke – push the saw all the way down.

Radial Arm Saw:
This tool is designed to cut wide boards (up to 12 inches). It is not appropriate for small pieces of wood. It is a powerful tool that allows for more than average exposure of its cutting surface. So be especially careful.

The saw is only set up to cut 90° angles. Do not try to change its angle.

Rest your material against the perpendicular guard rail that runs along the shop table.

The blade has a metal guard that raises itself as necessary. Never raise the guard by hand.

When you make your cut, be ready for the saw to kick. Never let go of the saw while its spinning. After you’ve made the cut, immediately slide the saw back to its starting position (WHICH ALWAYS SHOULD BE AS FAR AWAY FROM YOU AS IT WILL GO). Wait until the blade comes to a rest before letting go of the saw. Do not touch your subject until the blade is motionless.

Belt/disc Sander:
The sanders are used for smoothing out pieces of wood, and angling the edges of pieces of wood. Don’t be deceived into thinking that sanders are not at all dangerous because they lack metal cutting surfaces. Some of the nastiest shop injuries come from sanders.

Before setting up to sand, take careful note of the direction of travel of the band and wheel. They will tend to pull your subject in their direction. Always hold your subject firmly against the provided platforms. (Never free sand by holding your wood against some arbitrary point on the sanding surface.)

Also before you sand, inspect the sanding surfaces. If they appear to be worn smooth or torn, do not use them. Contact a staff member.

While you are operating the sander, be mindful of any unusual vibrations. If it begins to vibrate strongly, stop using it (turn it off), and contact a staff member.

NEVER use the sander on plastic or metal.

Grinder:
The grinder is used for smoothing or shaping small pieces of metal. Only metal. Be mindful of the downward rotation of the wheels. They will force the material you are grinding to move downward with them. You should always rest your subject on one of the platform in front of the wheel you are using so that it doesn’t get pulled out of your hand. Always leave the clear plastic debris shields in place – that is, between you and the thing that is being ground. If the wheels are damaged – if chunks are missing, or if they seem really worn out, don’t use it.

Band Saw:
The band saw is used to cut straight lines or curves in wood or plastic.

Before you operate the saw, ensure that the blade is not snapped, and that the doors to the blade pulleys are closed. Adjust the height of the blade guard just enough so that it will clear your material as you cut. Never run the saw with more blade than necessary exposed. When you are finished, return the guard to a very low position for the next person.

When you cut, make sure to keep your hand well away from the blade. When your cut is finished, turn off the saw and wait for it to come to a stop before you remove your material.

Scroll Saw:
If you change the blade, make sure to unplug the machine.

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