Hand and Power Tools - Blades and Cutter Materials

What is Carbide?

• A steel and carbon compound that is much stronger than regular steel.

• Spending time in your car.

• An epoxy and carbon compound that is much stronger than regular steel.

• A carbon and fiber compound that is much stronger than regular steel.

Answer explanation

Carbide is used to tip all kinds of cutters, such as drill bits saw teeth, and router bits. The bits shown started the same, but the steel shank wore out while the carbide tip is still the original size. I drilled over 2000 holes with the one on the right!

What is an abrasive blade?

• A rude blade that just does not get along with other blades

• A blade made from fine particles like the surface of sandpaper bonded together to form a blade or grinder wheel.

Answer explanation

The blades are round with no teeth and would typically be used in power tools with a rotating blade such as a demolition saw, cut-off saw, or circular saw. There are different abrasive blades for concrete and steel; CAUTION, they are not interchangeable

Small scissor like teeth are needed when

• Thin material that splinters easily is being cut, such as the veneer layer of plywood. Smaller teeth reduce splintering

• You cannot get a hold of Edward Scissorhands to do your cutting. Please read and understand the other option, that is what you need to know.

Answer explanation

NCCER likes to say that a plywood blade has scissor like teeth. What do you think they mean?

Carbide is better than "high speed steel" because (it)

• Has a stronger chemical bond that allows the microscopic edge to stay sharper through more wood cutting.

• Is good for lower speeds

• Is better for higher speeds

• the "high speed steel" chemical bond weakens at a lower heat than carbide, causing the cutter to become dull easier.

Answer explanation

Look closely at any cutters in the shop; do you see little pieces of metal attached to each tip? If yes, they are probably carbide tips. They are not hard to see if you look closely. The picture shows a steel bladed body with carbide tipped teeth.

A demolition saw wears its way through hard heavy materials such as concrete by rubbing through it at high speed with...

• Abrasive blades

• Carbon Fiber

• Carbide Tipped Blade

Answer explanation

Demolition Saws can also cut using segmented steel blades coated with diamond dust.

Order these from hardest cutters (first) to softest cutters (last): Carbide, Fiberglass, Steel, High-speed Steel.

• Carbide, Fiberglass, High-speed steel, Steel

• Fiberglass, Steel, High-speed steel, Carbide

• Carbide, Fiberglass, High-speed steel, Steel

• Carbide Steel, High-speed steel, Steel, Fiberglass

Answer explanation

Carbide is a carbon steel with tungsten. There are also compounds of carbon steel that include cobalt, vanadium, and others.

Which teeth are small, and considered scissor like by NCCER?

• 
• 
• 

Answer explanation

Yep, this blade is just made of steel with teeth cut into it and sharpened.

Which image shows a carbide tipped tooth?

• 
• 
• 

Answer explanation

Yep, this blade is made of steel with carbide teeth welded in place.

Which image shows diamond dust impregnated into the steel?

• 
• 
• 

Answer explanation

This blade allows the diamond dust to rub its way through concrete; diamonds are very, very hard. This is one type of abrasive blade

A demolition saw is...

• ...a liquid fuel or electric saw that wears its way through hard heavy materials such as concrete by rubbing through it at high speed with and abrasive blade.

• ... a diamond blade that can be used in a demolition saw. This is true, but not the answer here.

• ... an abrasive blade is much cheaper than a diamond blade, but cuts slower, makes more dust, and wears out quickly. This is true, but not the answer here.

Answer explanation

The blades are usually 12-14 " in diameter. Diamond blades are usually called "segmented". You would use this type saw if you needed to add a "door hole" to a brick building.