X-acto and Utility Knife Work Practices
The tricky part of using X-acto knives and utility knives is to avoid cutting yourself. These simple tools are frequently misused and many emergency room visits result.
1. Rest the piece being cut on a firm hard surface, never on your lap or in the palm of your left hand.
2. Always work with a sharp knife.
a. Keep the blade covered when not in use or when in storage. This will protect both you and the sharpness of the cutting edge.
b. Always have extra blades on hand. You will typically need them in the middle of the night.
c. Preserve your blade’s sharpness by cutting on soft, sacrificial surfaces, like plywood, chipboard or vinyl cutting mats, never on the hard melamine work table surfaces.
3. On thick or resistant material, cut with multiple passes or switch from an X-acto knife to the heavier duty utility knife. Remember: the more force you use pushing the knife, the less control you have over the cut. Rather than applying excessive force to your knife, cut your material with a saw.
4. When cutting along a straight edge, take care that the knife blade remains parallel to the straight edge for the entire length of the cut. This is not a natural motion; the hand would prefer to travel in an arc. If the knife is allowed to tilt towards the straight edge, it can deflect the straight edge or even skip up over the straight edge!
5. When cutting, the left hand is normally used to secure the work piece. Just take care to keep your left hand out of the path of the cut! Before making a cut, it often helps to “rehearse” your cut to both confirm that you have enough room to make the cut, and give your hand eye coordination a chance to prepare.
6. Discarded/used blades are just as dangerous as blades in use. Discarded blades should be wrapped/contained in such a way as to not have the blades exposed once they are placed in the garbage can.
Super Glue—Safe Work Practices
Because super glue is such an effective adhesive, it is essential that you not apply it to the wrong surfaces!
1. Do not squeeze on a bottle that is sealed shut! The bottle could burst open and spray glue everywhere. Instead open the nozzle with a pin.
2. Keep glue spatter out of your eyes: wear goggles!
3. If you get super glue in your eyes flush them immediately with water, then see a doctor. You may need antibiotic eye drops to prevent infection.
4. If you glue your skin to itself or to another material, do not tear the glue seam apart. Instead, dissolve the super glue with acetone (or lacquer thinner), which can be obtained in the model shop.
5. Super glue that dries on the skin will naturally wear away over a period of days.
6. Clean up spills by dabbing with a rag. If you wipe aggressively the rag may become bonded to the surface!
7. Work in a well ventilated area. Super glue gives off solvent fumes.
Lifting—Safe Work Procedures
Lifting heavy loads requires techniques for which the simple tasks of daily life do not prepare us. Poor lifting techniques frequently produce injuries ranging from smashed fingers to crushed toes to debilitating back injuries. Avoid these by:
1. Considering the lift before you make it.
a. Is the lift within your capability?
b. Would you do better with a helper, a lever or a dolly?
c. Can you stage the lift to occur in the zone between your knees and your shoulders, the zone where you will have the most strength?
d. If two are more people are lifting a load together, they must coordinate their movements in advance!
e. Will you need to prepare blocks or skids on which to set the load in order to avoid crushing your fingers?
f. If the load proves to be too great, can you set it back down without harming the object or yourself?
g. Do you have appropriate shoes for the task? (Hint: not flip-flops!)
2. Be sure you have a firm surface to stand on and remove any clutter from the path you will be traveling.
3. Lift with your legs, because your strongest muscles are in your legs.
4. Keep your back as straight as possible during the lift. Tucking your chin towards your chest is a good way to insure this.
5. Keep the load close to your body during the lift. Carrying a weight away from your body puts great strain on your back.
6. Lift with your feet spread apart and one slightly behind the other, so you can maintain your balance.
7. If you must turn while carrying a load, turn with your feet, never by twisting your back!
Welding and Cutting (General)—Safe Work Practices
Cylinder gases must be handled with extreme care because of the enormous pressure contained within the cylinders and because many of the compressed gases are flammable.
1. When you want to use the Prestolite or oxy-acetylene torches, the arc, MIG or TIG welders, have one of the shop’s staff set them up for you to use. Do not attempt to set them up or organize your work by yourself.
2. Gas cylinders must be solidly secured in a vertical orientation to protect the valves stems from accidental breakage.
3. Oil must never be used to lubricate the valve mechanism of cylinders. In combination with some gases it can be combustible.
4. When using the cutting torch, be conscious of where the spatter is directed to prevent fires and injury to other people.
5. The gas hoses are comparatively fragile things. Protect them from strain or damage.
6. Always light torches with a spark lighter, never a match or cigarette lighter.
7. Leather aprons, leather gloves, closed shoes and long pants must be worn when welding or cutting to protect from burns and spatter.
8. Clothing made from cotton or wool should be worn when welding because synthetic fabrics tend to melt when they catch fire, making burns injuries more severe.
9. Parts recently welded or cut are extremely hot and can cause severe burns if touched. Do not touch a piece of metal in the welding area without first checking to see if it is hot Welding gloves will be destroyed by contact with hot metal. Use gloves for protection rather than as a tool.
10. When using the hand grinder take care not to throw sparks onto other people or on combustible material. Use the welding screen if appropriate.
11. The hand grinder guard protects against grinding wheel fragmentation and accidental contact with unintended surfaces. Expose only the part of the grinding disk that you need to use.
12. When using the hand grinder cover your face with a full face shield to protect from accidental sprays of sparks. The oxy-acetylene flame and the electric arc produce intense light in the ultraviolet spectrum which can kill the cells on the retina of your eyes and cause sunburn on your skin.
13. Welder’s goggles must be worn when using the oxy-acetylene torches to protect the eyes from UV light damage.
14. Arc welding helmets, which have an even darker lens, must be worn when using the arc, MIG or TIG welders.
15. The welder’s screen should be positioned to shield welding activity from the view of unprotected people.
16. When chipping away the flux coating on arc welds the fragments of flux can be sharp and hot. Take care to protect your eyes from these fragments.