Shop Machinery and Tools Flashcards

Per OSHA, what is the maximum allowable gap between a bench grinder's work rest and the grinding wheel?

Answer: 1/8 inch

OSHA 1910.215 limits the work rest gap to 1/8 inch to keep work from being pulled between the rest and wheel.

When switching from a 1/4-inch to a 1-inch twist drill in the same mild steel, how should drill press spindle speed change?

Answer: Decrease it

Larger drills have higher surface speed at the same RPM, so RPM must be reduced.

What is the standard tap drill size for a 1/4-20 UNC thread?

Answer: #7 (0.201 in)

A #7 drill gives about 75% thread engagement for 1/4-20 UNC.

On an engine lathe, where should the cutting edge of a turning tool be set relative to the workpiece?

Answer: On the centerline

Setting the tool on center gives correct rake and clearance angles and prevents rubbing or digging in.

Before mounting a vitrified grinding wheel, what simple check detects hidden cracks?

Answer: Ring test

A sound wheel tapped lightly gives a clear ring, while a cracked wheel sounds dull.

When selecting a band saw blade, at least how many teeth should be in contact with the workpiece?

Answer: Three

At least three teeth in the cut prevents teeth from straddling the material and stripping.

Which hacksaw blade is best for cutting thin-wall electrical conduit?

Answer: 32 TPI

Fine 32 TPI blades keep at least three teeth on thin walls.