grinding

Question 1

wheel guards should extend what degrees past the vertical

Answer 1

30 to 45 degrees

Question 2

three basic types of surface grinders

Answer 2

horizontal spindle with reciprocating table
horizontal spindle with rotary table
vertical spindle with either reciprocating or rotary table

Question 3

what tolerance can a surface grinder get

Answer 3

less then 0.0001

Question 4

grinders typically run at what rpm

Answer 4

1750 rpm

Question 5

what grit is on the left side of a grinder

Answer 5

coarse

Question 6

what is truing on a grinder

Answer 6

getting the grinder wheel flat or straight

Question 7

4 most common natural abrasives

Answer 7

Crocus
Corundum or aluminum oxide
Emery
Diamond

Question 8

What are the three colours of aluminum oxide disks

Answer 8

Grey
Lighter grey
White

Question 9

Strength/weakness of grey aluminum oxide disk

Answer 9

Tougher and less brittle

Question 10

Strength/weakness of light grey aluminum oxide disk

Answer 10

Pure, more brittle and not as tough

Question 11

Strength/weakness of white aluminum oxide disk

Answer 11

The purest and the most brittle

Question 12

What are silicon carbide disks made from

Answer 12

Silica sand
Coke
Sawdust

Question 13

Green silicon carbide disks are used for what

Answer 13

Grind cemented carbides
Ceramics
Hard materials

Question 14

Black silicon carbide disks are used for what

Answer 14

Grind cast iron and soft non ferrous metals

Question 15

4 properties of abrasives

Answer 15

Hardness
Heat resistances
Toughness
Friability

Question 16

CBN stands for what

Answer 16

Cubic boron nitride

Question 17

Grit sizes range from

Answer 17

40 to 600

Question 18

parts of a grinder

Answer 18

nut
outer/inner flange
blotter
bushing
shaft

Question 19

the stronger the bond/grade the

Answer 19

softer the material

Question 20

3 common bonds

Answer 20

vitrified
resinoid
rubber

Question 21

what does load mean in abrasives

Answer 21

when your grinding and the material gets clogged in the abrasive

Question 22

what would a 15 be grain density

Answer 22

open structure

Question 23

Toughness in abrasives is what

Answer 23

Ability of material to resist impact and pressure

Question 24

Toughness in abrasives is what

Answer 24

Ability of material to resist impact and pressure

Question 25

Heat resistance in abrasives is what

Answer 25

Ability of material to withstand the heat of grinding without dulling

Question 26

Hardness in abrasive is what

Answer 26

Ability to scratch or penetrate another material

Question 27

Friability in abrasives is what

Answer 27

Ability of material to fracture under stress. Grain breaks off and presents new cutting edges

Question 28

What do the 6 positions mean when talking about the marking system

Answer 28

1 abrasive type 2 grain size 3 the grade 4 structure or density 5 bond type 6 manufacturers record

Question 29

What should the gap between the spark guard and the periphery of the wheel be

Answer 29

1/16 and 1/4 inch

Question 30

What does the blotter do

Answer 30

Protects the flanges from the abrasive grit Displays important information about the wheel

Question 31

What is dressing

Answer 31

Removes the top layer of abrasive particles to expose the fresh ones beneath

Question 32

What are the 4 dressers

Answer 32

Mechanical Abrasive stick Abrasive wheel Diamond

Question 33

Flanges should be at least what diameter

Answer 33

1/3 the diameter of the wheel