MOST

1
MOST

• Maynard Operation Sequence Technique
• Work Measurement System

2
Methods - Time Measurement

• H. B. Maynard was one of three persons
  instrumental in the creation of MTM.

3
Kjell Zandin, while working in the Swedish
Division of H. B. Maynard in the late 1960s,
detected striking similarities in the sequence of
MTM defined motions whenever an object was
handled.
4
Under MOST, the primary work units are no longer
basic motions as in MTM, but collections of these
basic motions dealing with moving object.
5
MOST makes the assumption that to move an object,
a standard sequence of events occurs.
6
Under MOST, objects can be moved in only one of
two ways

• They are picked up and moved freely through space
  -- the GENERAL MOVE.
• They are moved and maintain contact with another
  surface -- the CONTROLLED MOVE.

7
The MOST Family

• Basic MOST -- General Operations
• Mini MOST -- Repetitive Operations
• Maxi MOST -- Non-repetitive Operations
• Clerical MOST -- Clerical Operations

8
Maxi MOST is used to analyze operations that are
likely to be performed less than 150 times per
week.
9
Basic MOST is used for operations that are likely
to be performed more than 150 times but less than
1500 times per week.
10
Mini MOST is used to analyze operations likely to
be repeated more than 1500 times per week.
11
The Decision Diagram provides a simple procedure
for selecting the most appropriate MOST Work
Measurement System to use.
12
The MOST Decision Diagram is based on /- 5
accuracy and a 95 confidence level.
13
System Selection Charts may be used in lieu of
the Decision Diagram for choosing the best MOST
Work Measurement System to use.
14
The MOST Standard Form provides the analyst with
a simple, consistent format for analyzing work
using the method.
15
It should be possible to complete a MOST analysis
by observing two complete cycles of work in slow
motion.
16
If the method is well established and the analyst
knows the operation and conditions, the Basic
MOST calculations can be made from the office and
used to predict the times for a new procedure.
17
General Rules for Using MOST

• Each sequence model is fixed.
• No letter may be added or omitted for the General
  or Controlled Move Sequence.
• In general, no letter may be added or omitted for
  the Tool Use Sequence, with a few exceptions.

18
TMU

• TMU Time Measurement Unit
• 1 TMU 0.0006 minutes
• 1 TMU 0.036 seconds

19
How it works

• The purpose of the MOST system is to calculate
  the cycle time for an operation based on
  Pre-determined time study data.

20
Doing the math

• A typical MOST work sequence code would look like
  this
• A10 B6 G3 A6 P3 A0
• Step 1 add up all the subscript numbers
• 1063630 28
  (the subscript is the
  MOST index value)
• Step 2 Multiple the sum of the index by 10
• This answer gives the TMU equivalent
• 28 x 10 280 TMU
• Step 3 Convert to time
• 280 TMU .036 seconds 10.08 seconds
• 1 TMU

21
General Move Sequence
22
Four subactivities constitute the General Move
Sequence

• A Action Distance (mainly horizontal)
• B Body Motion (mainly vertical)
• G Gain Control
• P Placement

23
Roughly 50 of all manual work occurs as a
General Move.The percentage runs higher for
assembly and material handling and lower for
machine shop operations.
24
The General Move follows a fixed sequence of
steps

• Reach, either directly or in conjunction with
  body motions or steps.
• Gain control of the object.
• Move the object, as in reach.
• Place the object in temporary or final position.
• Return to the workplace.

25
The General Move Sequence Model

• A B G A B P A

26
Action Distance (A)

• This parameter is used to analyze all spatial
  movement or actions of the fingers, hands, and/or
  feet.

27
A0 lt 2 Inches

• This is any displacement of the fingers, hands,
  and/or feet a distance of 2 inches or less.

28
A1 Within Reach

• Actions that are confined to an area described by
  the arc of the outstretched arm pivoted about the
  shoulder.

29
A3 One to Two Steps

• The trunk of the body is shifted or displaced by
  walking, stepping to the side, or turning the
  body around using 1 or 2 steps.

30
More Than 2 Steps

• Used with Action Distance data table to cover
  longer movements.

31
Body Motion (B)

• This parameter is used to analyze either vertical
  motions of the body or the actions necessary to
  overcome an obstruction or impairment to body
  movement.

32
B3 -- Bend Arise, 50 Occurrence

• Bend Arise is required only 50 of the time
  during a repetitive activity.

33
B3 -- Sit or Stand without Moving Chair

• When the body is simply lowered into a chair from
  an erect position, without hand/foot motions
  required to manipulate the chair.

34
B6 -- Bend Arise

• From an erect standing position, the trunk of the
  body is lowered by bending from the waist and/or
  knees to allow the hands to reach below the knees.

35
B10 -- Sit or Stand

• A series of several hand, foot, and body motions
  to move a stool / chair into position followed by
  the body sitting or standing.

36
B16 -- Stand and Bend

• This is a case where a sitting person must stand
  up and walk to a location to gain control of an
  object placed below knee level, where a Bend
  Arise is required.

37
B16 -- Bend Sit

• This applies when gaining control of an object
  requires a Bend Arise followed by a Sit prior
  to placing the object.

38
B16 -- Climb On or Off

• This parameter variant covers climbing on or off
  a work platform on any raised surface (3 ft)
  using a series of hand and body motions to lift
  or lower the body.

39
B16 -- Passing Through Door

• Passing through a door consists of reaching for
  and turning the handle, opening the door, walking
  through the door, and subsequently closing the
  door.

40
Gain Control (G)

• This parameter is used to analyze all manual
  motions employed to obtain complete manual
  control of an object(s) and to subsequently
  relinquish that control.

41
G1 -- Light Object

• Gain control of an object by grasping it as long
  as no difficulty is encountered.

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G1 -- Light Objects Simo

• One hand gains control of a light object while
  the other hand obtains another light object.

43
G3 -- Light Object(s) Non-Simo

• While one hand is grasping an object, the other
  hand must wait before it can grasp the other
  object.

44
G3 -- Heavy or Bulky

• In grasping a heavy or bulky object there is a
  delay between when the object is grasped and when
  it begins to move due to weight, bulk, etc.

45
G3 -- Blind or Obstructed

• Access to the object is restricted because an
  obstacle prevents the operator from seeing the
  object or creates an obstruction to the
  hand/fingers in attempting to gain control.

46
G3 -- Disengage

• An application of muscular force to free an
  object from its surroundings typified by a need
  to overcome resistance followed by sudden
  movement and recoil of the object.

47
G3 -- Interlocked

• Interlocked means the object is intermingled or
  tangled with other objects and must be separated
  or worked free before reaching control.

48
G3 -- Collect

• Gain control of several objects jumbled together
  in a pile or spread out on a surface.

49
Placement (P)

• This parameter is used to analyze actions at the
  final stage of an objects displacement to align,
  orient, and/or engage the object with other
  object(s) before control of the object is
  relinquished.

50
P0 -- Pickup Objects

• This is placement in which no placement occurs.
  The object is picked up and held.

51
P0 -- Toss Object(s)

• Another placement where placement does not
  occur. The object is released during the action
  distance (A) parameter without placing motions
  or pause to point the object toward the target.

52
P1 -- Lay Aside

• The object is placed in an appropriate locations
  with no apparent aligning or adjusting motions.

53
P1 -- Loose Fit

• The object is placed in a more specific location
  than described by the Lay Aside parameter, but
  with tolerances so loose that only a modest
  amount of control is needed for placement.

54
P3 -- Adjustments

• Adjustments are defined as the corrective actions
  occurring at the point of placement, and
  recognized by obvious efforts, hesitations, or
  correcting motions to align, orient, and/or
  engage the object.

55
P3 -- Light Pressure

• Because of close tolerances or the nature of the
  placement, the application of muscular force is
  needed to seat the object.

56
P3 -- Double

• With double, two distinct phases occur during
  the total placing activity.

57
P3 -- Loose Fit Blind

• In this case the operator must feel around for
  the placement location before a loose placement
  can occur.

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P6 -- Care or Precision

• Extreme care is needed to place an object within
  a closely defined relationship with another
  object, and characterized by the obvious slow
  motion of the placement due to the high degree of
  concentration required.

59
P6 -- Heavy Pressure

• As a result of very tight tolerances, a high
  degree of muscular force is needed to engage the
  object.

60
P6 -- Blind or Obstructed

• Accessibility to the point of placement is
  restricted because an obstacle prevents the
  operator from seeing the point of placement, or
  creates an obstruction to the hand/fingers when
  attempting to place the object.

61
P6 -- Intermediate Moves

• Several intermediate moves of the object are
  required prior to placing.

62
General Move Example

• From a stack located 10 feet away, a heavy object
  must be picked up and moved 5 feet and placed on
  top of a workbench with some adjustments.

63
General Move Example

• An assembly worker gets a handful of washers (6)
  from a bin located within reach and puts one on
  each of six bolts located within reach, which are
  four inches apart.

64
General Move Example

• A worker gains control of two fittings that are
  within reach and located more than two inches
  apart, one at a time, and places them on separate
  trays that are within reach and located less than
  2 inches apart.

65
Controlled Move Sequence
66
Three new subactivities are found in the
Controlled Move Sequence
M Move Controlled X Process
Times I Align
67
The Controlled Move Sequence describes the manual
displacement of an object over a controlled
path.
68
The Controlled Move follows a fixed sequence of
steps
Reach, either directly or in conjunction with
body motions or steps. Gain control of the
object. Move the object over a controlled
path. Allow time for the process to occur. Align
the object after the move/process. Return to the
workplace.
69
A Controlled Move is performed under the
following conditions

• The object or device is restrained by its
  attachment to another object
• Its controlled during the move by the contact it
  makes with the surface of another object.
• It must be moved on a controlled path to
  accomplish the activity.

70
Move Controlled (M)

• This parameter is used to analyze all manually
  guided movements or actions of an object over a
  controlled path.

71
M1 -- One Stage lt 12

• Object displacement is achieved by a movement of
  the fingers/hands/feet not exceeding 12 inches.

72
M1 -- Button/Switch/Knob

• The device is actuated by a short pressing,
  moving, or rotating action of the
  fingers/hands/wrist/feet.

73
M3 -- One Stage gt 12

• Object displacement is achieved by a movement of
  the hands, arms, or feet, plus body motion,
  exceeding 12 inches.

74
M3 -- Resistance, Seat/Unseat

• Conditions surrounding the object or device
  require that resistance be overcome prior to,
  during, or after the Controlled Move.

75
M3 -- High Control

• This parameter reflects the need to align an
  object using a high degree of visual
  concentration.

76
M3 -- Two Stages lt 12

• An object is displaced in two directions or
  increments a distance not exceeding 12 inches per
  stage without relinquishing control.

77
M6 -- Two Stages gt 12 -- OR-- With One - Two
Steps

• An object is displaced in two directions or
  increments a distance exceeding 12 inches per
  stage without relinquishing control.

78
M10 -- Three to Four Stages --- OR --- 3 -
5 Steps

• An object is displaced three or four directions
  or increments without relinquishing control or
  pushed/pulled on a conveyor belt.

79
M16 -- Move Controlled with 6 - 9 Steps

• Push or pull an object(s) using 6 - 9 steps.

80
Cranking action is performed by moving the
fingers, hand, wrist, and/or forearm in a
circular path more than half a revolution. Less
than this is considered a Push/Pull/Pivot.
81
Push - Pull Cranking

• If cranking results in a back - and - forth
  movement of the elbow instead of pivoting at the
  wrist and / or elbow, it is considered push -
  pull cranking.

82
Pivotal cranking is more efficient than push -
pull cranking, and should be used whenever
possible.
83
Process Time

• Process time is that portion of work controlled
  by electronic or mechanical devices / machines,
  not by manual actions.

84
As a rule of thumb, the process time expressed as
an index number should not exceed 20 of the
cycle time.
85
Alignment refers to manual actions following the
Move Controlled or at the conclusion of process
time to achieve an alignment or specific
orientation of objects.
86
Within the area of normal vision (a 4 diameter
circle), the alignment of an object to two points
can be performed without any additional eye
times.
87
I1 -- To One Point

• Following a controlled move, an object is aligned
  to one point.

88
I3 -- To Two Points lt 4 Apart

• The object is aligned to points not more than 4
  inches apart following a Controlled Move.

89
I6 -- To Two Points gt 4 Apart

• The object is aligned to points more than 4
  inches apart following a Controlled Move.

90
I16 -- Precision

• The object is aligned to several points with
  extreme care or precision following a Controlled
  Move.

91
I3 -- To Workpiece

• A Machining Operations parameter where the
  machine tool is aligned to the workpiece prior to
  making a cut.

92
I6 -- To Scale Mark

• Another Machining Operations parameter, the
  machine tool is aligned to a scale mark prior to
  making a cut.

93
I10 -- To Indicator Dial

• The third Machining Operations parameter, the
  machine tool is aligned to the correct indicator
  dial setting prior to making a cut.

94
Alignment of Nontypical Objects

• Nontypical objects are those that are especially
  large, flimsy, sharp, or require special handling.

95
Alignment of a nontypical object normally takes
place as a series of short correcting motions (lt
2) following the Controlled Move, usually with
the assistance of stops, guides, or marks.
96
Controlled Move Example

• From a position in front of a lathe, the operator
  takes two steps to the side, turns the handwheel
  two rotations, and sets the cutting tool by
  aligning the handwheel dial to a scale mark.

97
Controlled Move Example

• A milling machine operator walks four steps to
  the quick-feeding cross lever and engages the
  feed. The machine time following the 4 lever
  action is 2.5 seconds.

98
Controlled Move Example

• A material handler takes hold of a heavy carton
  with both hands and pushes it 18 across conveyor
  rollers.

99
Controlled Move Example

• Using the foot pedal to activate the machine, a
  sewing machine operator makes a stitch requiring
  3.5 seconds process time. The operator must
  reach the pedal with the foot.

100
The Tool Use Sequence is a combination of the
General Move and Controlled Move activities.
101
Tools not listed in the tables that are similar
to a tool in the table can use their time values
for analysis.
102
Tool Use Phases

• Get Tool (Object)
• Put Tool (Object) in Place
• Use Tool
• Put Tool (Object) Aside
• Return

103
The Tool Use Sequence model makes use of the A,
B, G, and P parameters, which are all
familiar to us, plus the new Tool Use parameters.
104
The Tool Use Sequence Model

• A B G A B P A B P A
• consists of the tool use parameters F, L, C,
  S, M, R, T.

105
Tool Use Sequence Parameters

• F -- Fasten
• L -- Loosen
• C -- Cut
• S -- Surface Treat
• M -- Measure
• R -- Record
• T -- Think

106
Fasten / Loosen

• Manually or mechanically assembling or
  disassembling one object to or from another using
  the fingers, a hand, or hand tools.

107
Index values for F and L are determined by
the body member performing the action.
108
Finger Spins are the movement of the fingers and
thumb to run a threaded fastener down or out, and
include a light application of pressure for
seating / unseating the fastener.
109
Wrist Actions

• Wrist Turn
• Wrist Stroke (with reposition)
• Wrist Crank
• Tap

110
Wrist Turn

• During a wrist turn, the tool is not removed from
  the fastener during use and not repositioned on
  the fastener after an action.

111
Wrist Stroke (with reposition)

• In this tool use, after each stroke with the tool
  and before making each subsequent stroke, the
  tool must be removed from the fastener and
  repositioned.

112
Wrist Crank

• Wrist crank applies to tools that are spun or
  rotated around a fastener while remaining affixed
  to it.

113
Tap

• This parameter covers the use of a hammer (or
  similar device) to exert short tapping motions by
  pivoting the hand at the wrist.

114
Arm Actions

• Arm Turn
• Arm Stroke (with reposition)
• Arm Crank
• Strike
• T-Wrench (two hands)

115
Arm Turn(s)

• Arm Turn(s), applying to ratchets, occur when the
  tool is held near the end of the handle,
  resulting in a pulling action on the tool.

116
Arm Stroke (with reposition)

• Following each stroke or pull with the tool, it
  must be removed and repositioned again on the
  fastener before making a subsequent pull.

117
Arm Crank

• The tool is used with a circular movement of the
  forearm as it is pivoted at the elbow or the
  shoulder to push or crank the tool around the
  fastener.

118
Strike

• Strike is the use of a hammer with an up - and -
  down motion performed with the hand as it is
  pivoted from the elbow.

119
T-Wrench (two hands)

• A two - handed arm action, including the reach
  for each hand to the opposite handle before
  making the next turn, and involving a 180 degree
  turn of the T-wrench with each action.

120
Power Tools

• The use of electric and pneumatic power wrenches
  to run a standard threaded fastener down or out a
  length 1 1/2 times the bolt diameter.

121
The time values generated by the data card for
power tool use must be compared to the times
generated by the tools used in the shop, and
adjusted if necessary.
122
Torque Wrenches

• F6 -- Torque wrench handle length to 10.
• F10 -- Handle length from 10 - 15.
• F16 -- Handle length from 15 - 40.
• In all cases, the value is for one arm action and
  includes the time either to align the dial or to
  await the click.

123
Tool Placement

• As a general rule, the P parameter for the
  Fasten / Loosen tools will carry the index values
  indicated in the Tool Placement table.

124
Tool Use Frequencies Example

• An operator picks up a screwdriver within reach
  and tightens two screws with six wrist turns each
  and then sets aside the screwdriver.

125
Multiple Tool Actions Example

• A screw is fastened with a screwdriver. A total
  of 18 spins and 4 wrist turns are necessary.

126
Multiple Tool Actions Example

• A nut is fastened with a ratchet wrench.
  Following 3 wrist cranks, 6 wrist turns are
  applied.

127
Tool Use Example -- F / L

• Obtain a nut from a parts bin located within
  reach, place it on a bolt, and run it down with 7
  finger actions.

128
Tool Use Example - F / L

• Pick up a small screwdriver that lies within
  reach and fasten a screw with 6 finger actions,
  and set aside the tool.

129
Tool Use Example -- F / L

• Obtain a power wrench that lies within reach, run
  down four 3/8 bolts located 6 apart, and set
  aside wrench.

130
Tool Use Example -- F / L

• From a position in front of an engine lathe,
  obtain a large T-wrench located 5 steps away and
  loosen one bolt on a chuck on the engine lathe
  with both hands using five arm actions. Set
  aside the T-wrench from the machine, but within
  reach.

131
Cut

• Pliers
• Scissors
• Knife

132
Pliers

• C3 -- Soft Using pliers with one hand and
  making one cut.
• C6 -- Medium Using pliers with one hand and
  making two cuts.
• C10 -- Hard Using the pliers with two
  hands and making two cuts.

133
Pliers

• C1 -- Grip Using pliers to hold an item and
  subsequently release the pressure on the item.
• C6 -- Twist Close pliers jaws on two wires and
  use two twisting actions to join the wires
  together.
• C6 -- Form Loop Close pliers jaws on wire and
  using two actions, bend loop in end of wire.
• C16 -- Secure Cotter Pin Use pliers to bend both
  legs on cotter pin to hold it in position.

134
Index values using scissors are selected
according to the number of cuts used.
135
Tool Use Example -- Cut

• An operator picks up a knife from a workbench two
  steps away, makes one cut across the top of a
  cardboard box, and sets aside the knife on the
  workbench.

136
Tool Use Example -- Cut

• During a sewing operation, a tailor cuts the
  thread from the machine before setting aside the
  finished garment. The scissors are held in the
  palm during the sewing operation.

137
Tool Use Example -- Cut

• Following a soldering operation, an electronic
  component assembler must cut off the excess small
  - gauge wire from a terminal connection. The
  pliers are located within reach.

138
Tool Use Example -- Cut

• An electrician working on transmission lines
  takes a pair of pliers from the tool belt and
  cuts off a piece of line. The line is heavy,
  such that 2 hands are needed to cut through the
  wire.

139
Surface Treat

• Surface Treat covers the activities aimed at
  cleaning material or particles from or applying a
  substance, coating, or finish to the surface of
  an object.

140
Index values for cleaning tools are based
primarily on the amount of surface area (sq. ft.)
cleaned.
141
Tool Use Example Surface Treat

• Before marking off a piece of sheet metal (4 ft
  sq) for a cutting operation, the operator takes a
  rag from his or her back pocket and wipes an oily
  film from the surface.

142
Tool Use Example Surface Treat

• Following a sanding operation, an operator
  standing at a workbench picks up a brush located
  within reach and brushes the dust and chips from
  the working are (6 ft sq), and then sets aside
  the brush on the workbench.

143
Tool Use Example Surface Treat

• Before assembling three components to a casting,
  the operator obtains an air hose (within reach)
  and blows the small metal filings left from the
  previous machining operation out of 3 cavities.
  The distance between cavities is gt 2.

144
M10 -- Profile Gauge

• Used to compare the profile of an object to that
  of the gauge.

145
M16 -- Fixed Scale

• Covers the use of a linear (yardstick) or angular
  (protractor) measuring device.

146
M16 -- Calipers lt 12

• Covers the use of vernier calipers with a
  capacity to 12 inches.

147
M24 -- Feeler Gauge

• Covers the use of a gauge to measure the gap
  between two points.

148
M32 -- Steel Tape lt 6 Ft.

• This parameter covers the use of a steel tape to
  measure, from a fixed position, between two
  points.

149
Micrometers lt 4

• M32 -- Depth measurement
• M42 -- Outside diameter measurement
• M54 -- Inside diameter measurement

150
Tool Use Example -- Measure

• Before welding two steel plates, a welder obtains
  a square and checks the angle between the plates
  to see that it is correct. The square (a profile
  gauge) is located three steps away on a workbench.

151
Tool Use Example -- Measure

• Following a turning operation, a machinist checks
  the diameter of a small shaft with a micrometer.
  The micrometer is located on and returned to the
  workbench 2 steps away.

152
Measure Supplemental Values

• M6 -- Snap gauge OD to 2
• M10 -- Snap gauge OD to 4
• M16 -- Plug gauge go/no-go to 1
• M24 -- Thread gauge go/no-go int/ext to 1
• M24 -- Vernier Depth Gauge to 6
• M42 -- Thread gauge go/no-go int/ext 1-2

153
Record

• Write covers routine clerical activities.
• Index value based on number of digits or words
• Mark covers marking object
• Each mark is considered a digit

154
Tool Use Example -- Record

• After finishing an assigned job, the operator
  picks up a clipboard and pencil (simo) from the
  workbench, fills out the completion date on the
  job card, and signs his name. He then returns
  the board and pencil to the workbench.

155
Tool Use Example -- Record

• To order a part, a clerk takes a pencil from her
  shirt pocket and writes a six-digit part number
  on the requisition form on her desk. She then
  clips the pencil back in her pocket.

156
Tool Use Example -- Record

• Part of a packing operation involves identifying
  the components in the carton. This involves
  picking up a felt marker (within reach) and
  marking a 6-digit number on the container.

157
Think

• Most of the time think occurs internal to the
  manual work, but there are times it must be
  considered as a separate activity.

158
Think -- Inspect

• The type of inspection work were looking at here
  is that where only simple yes / no decisions
  are quickly made on the existence of a particular
  defect in a part.

159
Inspect -- Read

• The column Digits or Single Words is to be used
  for reading technical data (part numbers, codes,
  quantities, etc.)
• The column Text of Words is used when analyzing
  situations in which the operator reads words
  arranged into sentences or paragraphs.
• Other, specialized, values exist for reading
  gauges, scales, date/time, tables.

160
Tool Use Example -- Think

• During a testing operation, an electronics
  technician picks up a meter lead, places it on a
  terminal, and reads voltage off the meter scale.
  The lead is then put aside.

161
Tool Use Example -- Think

• Prior to starting a turning operation, an
  operator picks up a work order set and reads a
  paragraph that describes the method to be
  followed. It contains an average of 30 words.
  The operator then places the set aside on the
  workbench.