Toolipedia: Utility Knives

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What is a utility knife?

A utility knife is a hand tool that nearly all trades and hobbyists use. Because of its sharp blade, compact size and ease of operation, a utility knife is a great tool to have on hand whenever something needs to be cut. In drywalling operations, it is the most common tool to use when cutting drywall to length or width. The utility knife has been around for decades and as such there are a wide variety of configurations on the market. Here are the basic parts of a utility knife:

1. Handle
2. Button to extend and retract the blade
3. Blade
4. Quick Blade Removal Button (optional)
5. Built in blade storage (optional)
6. Line/String Cutting Notch (optional)

A utility knife is often also referred to as a box cutter or a razor blade. It is used by nearly every trade and homeowner and some models fold in the middle so that it can be carried like a pocket knife.

How is a utility knife used?

Operation basics (for drywall use)

• Mark the line where the drywall needs to be cut
• Score the line with the utility knife
• Flex and tap the dry wall on the opposite side of the line that has been scored
• Once the gypsum in the drywall has broken, fold the drywall back towards itself
• Score and cut through the paper of the opposite side to complete the cut

Accessories needed:

• Extra blades
• Alternative blades (like hook blades used in roofing) for other application

Safety

• Utility knives are very sharp be careful when cutting, keep fingers away from blade
• According to safety recommendations, duller blades pose even greater risk of cutting due to the increased force used to cut items; change blades when dulling occurs

What are the different types of utility knives?

• Most fixed handled utility knives have blade storage in their handles
• Older utility knives have a screw(s) that holds the body together and must be removed to switch blades and to get to stored blades
• Some utility knives have a quick release button for the blade
• Some utility knives have folding handles that make them function like pocket knives
• Some utility knives have a guard where the blade comes out of the handle, which only allows the blade to be slightly exposed – these are usually used for boxcutting
• Some utility knives have a spring loaded button to extend the blade; once your finger is off the button the blade will retract – these are considered safety utility knives
• Some utility knives have blades that run through the body of the knife and are scored at segments; when the tips go dull the blade segment can be snapped off

What makes a good utility knife?

• Ergonomic grip
• Heavy Body Construction
• Blade extension and retraction button operates smoothly
• Easily accessible blade storage
• Quick release blade change is easily used

Stanley makes high quality utility knives. 

Utility Knife Tips

Don’t continue to use the blade when cutting becomes difficult it makes the work harder and can be dangerous.

Using a straight edge to initially score drywall can give a cleaner cut

Keep drywall folded as far back as possible when finishing the drywall cut, this increases the likelihood that back cut will be cleaner and straighter.

Article source here: Toolipedia: Utility Knives