lean production system whitepaper 4apr05 · 2018-11-11 · 2. principles of lean and 5 s 2-1 basic...

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EXPIRA Lean Six Sigma http://www.expira.se Säte: Stockholm

© H Södersved EXPIRA D:\DOK\ARTIKLAR\LEAN_Production_System_WhitePaper_4apr05.doc 2011-11-26 Rev A 1

The LEAN Production System Reprints from research trips to Japan 1982-1993

© Håkan Södersved, EXPIRA

General aspects l-l. Why you need a LEAN system? The manufacturing industry has been changing its role from hardware to software oriented one, which means that the current makers have to produce such go ods as to motivate users to buy. In this context, the concept of Quantity/Quality-Cost-Delivery Time (QCD) has been enlarged into PQCDS.

• P – Products segmented and characterized users want to buy • Q – Quantity and quality to fit users desire • C – Cost, as low as possible • D – Delivery time to satisfy users' requirement • S – Safe products

The old style of the manufacturing industry has to realize t hat its role should not be just to make goods but to do so in the wake of users' demand. Under the severe ly demanded condition, the manufacturing industry should innovate its production system. Here is a reason why LEAN comes into a picture.

0utline of LEAN 1. LEAN Production Management

The production management is composed of the two phases.

a) Management system – Organization : Soft b) Facilities – Machinery : Hard

The LEAN Production Management system aims at matching production management to market needs.

1-1 What is LEAN?

A. "Just" is a core of the LEAN, it is not "in time" but "Just In Time ". B. LEAN is a company-wide activity for the purpose to get rid of all kind s of MUDA (uselessness and waste). Thus LEAN can be seen as a MUDA MANAGEMENT SYSTEM.

• MUDA of overproduction • MUDA of goods in process • MUDA of inventories

After kicking out all the MUDA fro m a factory, material and products would flow like a river stream.

C. The total scheme of LEAN system is illustrated by the Table 1.

EXPIRA The LEAN Production System


Table l. The scheme of LEAN production system

1-2 How to implement LEAN system?

The difference between LEAN and IE ( Industrial Engineering ) is as follows.

• IE – the ind uctive method based o n data colle cted by fact analysis using a video (stop watch)

• LEAN – the deductive method to innovate a f actory with a target to materialize the LEAN concept

It is constituted by several elements enumerated as follows.

A. Conscious change

• To banish old constitutions • To create a crisis sense on the present conditions • To execute conscious change by the strong leadership of a top management • To convert a real/faked company-wide crisis into massive energy

B. Bases of factory improvements

• 5 S – The core of the bases • To execute 5 S - SEIRI, SEITON, SEISO, SEIKETSU, SHITSUKE (explained later) • To carry out SEIRI and SEITON so as to be seen by eyes – Where, What, How Many • SEIRI by eyes – Red tag operation • SEITON by eyes – KANBAN operation

C. Flowing production

• The flowing production aims at brin ging all the MUDA up on visible stages while the lot production hides MUDA

• Prerequisites of A Flow Production 1. Line production 2. Small and exclusive machines 3. Processing a work One by One 4. Multi-processing workers – A wor ker should work with flexibility f or several

processes



5. Standing operation – Workers should be standing while working D. Leveling (Heijunka)

• It is not at all makers but custo mers' needs that deter mine production capa city and manufacturing pitches of production

• Volume and varieties of products must be balanced by each process E. Standard operations

• To prepare effective combination of 3 M (MAN, MACHINE and MATERIAL) • Standard operations mean various ways of achieving 5 S. • Procedures…

1. To analyze all the jobs and to make them visible 2. To find troubles and problems based on Tact Time 3. To pursue causes behind the problems by asking: "Why, Why , Why, Why and Why? " 4. To make improvement plans 5. To implement plans 6. To set standard operations

1-3 Structure of introducing the LEAN production system

• The LEAN production system is a factory innovation to figh t against fixed ideas and old

characters rooted in factories • A strong will of top management and active attitudes of workers is key • Aiming at changing the production processes, a LEAN promotion project should be set up

in a company • A president should be a total le ader of the project. Factory managers and division

managers should be responsible to clarify goals and execution plans • Section chiefs and job leaders sho uld take care of instruct ions, education and training o f

workers • Workers should be in charge of generating good ideas and carrying out plans

2. Principles of LEAN and 5 S 2-1 Basic spirits of LEAN

1. To destroy the fixed ideas of production 2. To consider how to do instead of thinking why impossible 3. To deny the present situation and not to excuse anything 4. To do good things at once and stop bad things at once 5. To correct errors/defects at once 6. To repeat "Why" five times to find the Root Cause (Point Of Cause = POC) 7. To realize that good ideas may come out through problems 8. To rely on 10 workers' wisdom in stead of one's inspiration 9. To know improvement has no end

2-2 Fundamentals of LEAN

Meaning of LEAN The sense of LEAN is t o secure "Just In Time" according t o conditions such as month, day, ho ur, minute or second. The target is to zoom up all MUDA stained in factories so that everybod y could see them. The LEAN is a technique to banish MUDA perfectly.

MUSIC

The production without MUDA sounds like a music. Flowing production is a melody, leveling makes rhythms and standard operation creates a harmony.



Productivity Productivity has been d efined conventionally by Output/Input. It is a false productivity containing MUDA of overproduction and inventories. A real pro ductivity should be determined by Demand/Input. The output should be volume demanded by customers.

Efficiency

The conveyer system hides adju stment MUDA – a quick worker slows down her speed to fit a pitch time. So the production efficiency should be counted by the whole line, which can lead to the company-wide efficiency. LEAN is a system to take th is kind of MUDA out and accomplish a smooth flow of work.

MUDA of big machines A factory is apt to in stall a big machine in order to improve only one process which results in disturbing the total f low of production. Withou t improving operations, improving machines of ten causes a mechanical MUDA. Ad vanced machines make a manufacturing to be the transportation or warehouse industry with a fixed amount of MUDA. Expensive ma chines force a factory to increase operating ratio of the machine, which will produce unnecessary goods.

Moving and working

• Working is an operation to put Added Value on products while moving is actions not needed by products

• All the movements are MUDA • The origin of LEAN is to separate working from moving

Examples of moving MUDA: • Carrying parts • Counting parts finished • Loading goods on a carriage from a floor • Transferring bagged parts to the next process • Taking out parts from a bag • Making parts for tomorrow • Holding down a position of parts • Repeating a cycle – taking parts, switching on, processing • Watching a machine • Looking for something

Transporting something is by all means MUDA since value is added by a machine. Transportation should be eliminated by 5 S.



2-3 5S

What is 5S? A factory is created by 5S and destroyed by 5S . Factory rat ionalization and improvements start from 5S.

A. SEIRI (Sorting out) – To throw away unnecessary things and keep only necessary things. SEIRl by eyes – All the arrangement should be visible. A Red tag operation – A red tag is to be labeled on all unnecessary things. B. SEITON (Arrange, put in right order) – To standardize how to put neeessary things in order so that everybody could see them. SEITON by eyes – All the SEITON should be visible. A Kanban operation – A kanban plate is to be placed on necessary things. C. SEISO (Cleaning, maintaining) – A clean, well maintained factory can produce goods with high quality. D. SEIKETSU (Standardization) – To mainta in the above 3S. LEAN aims at making a mechanism not to make a factory dirty instead of cleaning it after becoming dirty. E. SHITSUKE (Good manners and behaviour) – To habituate workers to ke ep rules formulated by everybody.

Effects of 5S

A. MUDA zero - cost reduction - eliminate useless spaces - eliminate useless inventories - eliminate useless carriers - eliminate useless machines - eliminate useless movements B. Injuries zero - safety up - clean machines: easy to find defects and risks - making passages C. Trouble zero - maintenance easy - prolongation of machine life D. Defects zero - quality up



- visible defects - eliminate mixing of parts E. Preparation zero - produce of variety of products - eliminate looking for something - find out anything at once - eliminate wrong jigs and tools F. Delay zero - exact delivery time - increase processing speed - eliminate defects G. Claim zero - good reputation

Red tag operation – visible SEIRI

Procedure • Put red tags on unnecessary things chosen by a production schedule – a selection criteria • Move these to a red tag storage – only necessary things are left at production sites • Throw away red tagged things • Execute a red tag operation regularly as a company-wide standardized activity • Classify red tagged objects into defects, dead stock, stored goods and non-book keeping

things Kanban tag operation - visible SEITON

Procedure • Decide where to place • Arrange racks – first-in first-out principle. Display addresses • Display goods – what to deposit: display items

- what to be deposited: display places • Display quantity

- Show maximum inventory level by a red tape - Show minimum inventory level by a blue tape

SHITSUKE - make the rules a daily habit for all workers - standardize how to store things

3. Flowing production and multi-processing 3-1. Flowing production

Inventories are companies’ graveyards – why so?

A. Interest burden gets heavy and capital gets fixed B. Inventory costs go up and do not contribute to profits C. Inventory causes useless work load. It stops the flow of material and needs transportation D. Inventory requires extra management resources E. Inventory eats parts needed for next products

These drawbacks have been commonly recognized but the real problem is that inventory obscures all the problems in comp anies. There is an intention to use inventories as buffer for troubles and problems. For instance producing a variety o f products g enerates inventories. Workers should here think why t he inventory has been produced. The “wh y " leads to



improvement of the process. And workers can discover the best way to chang e products online. See fig 2.

The lot production and flow production

The lot production is a block production and the flow production is p rocessed One by One. The lot production hides MUDA. The difference between the two production syste ms is listed below.

A. Processing Lot – a worker processes many pieces at one process – works accumulated Flow – a worker processes one piece and then moves to another process – works flow B. Layout of machines Lot – job shop Flow – line c. Rationalization Lot – a worker operates many machines Flow – a worker operates many processes D. Workers Lot – mono-talent worker – a pressman is a pressman Flow – multi-talent worker – different kind of machines E. Flow of material Lot – a lot is a production unit – the next machine is far Flow – one piece is a production unit – the next machine is near F. Goods in process



Lot – inventories of goods in process Flow – no inventories G. Lead time Lot – longer lead time waiting for the coming lot Flow – amassed real processing time H. Machines Lot

• machines are keys and a production pitch is a core • machine speed is required to be high • versatile functions • big size and expensive • working ratio of machines

Flow • total flow is a key • functional minimum, special and exclusive machine • small size and inexpensive • maintenance and machining ratio are more important than working ratio

Requirements for the flow production

1. The key is One by One processing 2. LEAN production is not an improvment of inherent production technology but of processing

magnitudes 3. LEAN pursues the meth od generating no defe ct items by means of the One by One flow

production

A. One-by-One flow – revealing dormant MUDA (uselessness) B. Machine layout – revealing transportation MUDA C. Synchronization – each process works under the same pitch (Frequency = Tact Time) – the pitch is decided by customers D. Multi-processing – a worker and material move together E. Multi-talent workers F. Standing operation – standing makes workers aggressive G. Small machines – eliminating useless functions of machines H. U-shaped line – IN/OUT meeting together



3-2. Multi-processing

Differences Mono-processing – Multi-processing. A worker engaged in multi-processing feels more human than in mono-processing. Feeling human accords to productivity.

A. Mono-processing A press worker handles several pressing machines = Mono-talent

B. Multi-processing A press worker handles a press, milling machine, drilling machine etc. one after another. Benefits:

1. You eliminate surface defects 2. You solve overproduction 3. You know reasons for failure of products 4. You conduct your own inspection – building quality into the product

• You take away MUDA of goods in process • You get rid of MUDA in spaces, transportation, and holding parts in processes • You shorten the lead times



Prerequisites for the Multi-processing A. U-shaped line structure – eliminating unnecessary movements of workers going back and forth to handle parts. Easy co-operation and communication between workers B. Eliminating an isolat ed island – the main stream of production is composed of raw material, processing, assembling and in the e nd – shipment to custo mers. In factories, there can be see n blocks isolated from the stream like islands, bigger and smaller. These are nests of MUDA C. Small machines – the first step of the line production D. Standing operation – flexibility, rapid response and better health E. Development of multi-processing workers F. Separation of workers from machines – workers should be apart from working machines so that they can do other jobs G. PokaYoke – Machines should b e devised to check fa ilures and mistakes by workers (POKA YOKE) – autonomous controlling function of machines F. Jidoka – Machines are improved so as to generate no defective parts

Multi-processing and few workers

Manpower saving is a way to redu ce just power in such a manner th at a worker is watching a machine instead of operating it. This is increasing cost. A genuine manpower saving should be a way to decrease the numb er of workers by means of fostering workers capable to operate many machines and processes. Consequently a production line shall consist of multiprocessing workers. The number of workers should not be fixed b ut flexible according to momentary conditions of lines.

4. Standard operation and JIDOKA 4-1. Standard operation

What is a standard operation? A. The standard operation is a way to make the best achievement of PQCDS by means of the optimum combination of the 3 M (MAN, MACHI NE and MATERIAL). While an operation standard means the standard of each finit unit operation. B. The production sta ndard is a standard to manufacture products through combining unit operations.

Three elements of the standard operation

A. Tact Time – Time needed for processing one piece of works – depending on production volume and operating time of machines B. Operation orders – Workers' operation order, not an order of material flow C. Standard stocks – Minimum volume of goods in process at worker site

Standard operations table

In order to prepare a standard operation table, it is important to list all the operations, not keeping them hidden. Visibility of all operations is core. Tables of standard operations are prepared by the following process.

A. Capacity table of parts – parts processing capacity of each process B. Matrix of standard operations – benchmark is Tact Time C. Operation instruction for workers D. Standard operation order papers

- Layout of machines - Tact time - Operation orders



- Work piece stock

Standard operations and operation improvements A. To improve the mechanism of material flow – elimination of big MUDA

• To process One by One – One piece flow • To improve the layout – flow shop

B. To improve ways of operation– multi-processing • One worker takes care of a product from the beginning to the end

C. To improve motions – eliminating useless motions – moving MUDA D. To standardize operations

• Anybody can do the same jobs o operation improvement o machine improvement

small and exclusive machine man machine separation

• man: adding human value on materia • machine: adding mechanical value on materia

improving machines – not producing defective products • self-stopping machine when near to make defects

Standard operation and leveling • Customers are tended to buy goods whenever and however they want • Manufacturers should make those, whatsoever, whenever and however needed • The lot production system causes:

o MUDA of overproduction o MUDA of inventories on lines o MUDA of transportation o MUDA of inventories o MUDA of management

• The leveled production aims at thoroughly leveling different types of products and volumes o Tact Time: time to make one piece o Daily production quantity = monthly production quantity/operation days o Tact Time = operation hours/production volume

JIDOKA

A. JIDOKA and Automation 1. JIDOKA – automation to increase Added Value 2. Automation – just movi ng machines, often workers must be monitoring, eating labor

and machine costs B. How to introduce JIDOKA?

1. Step l – Manual production of all products 2. Step 2 – Machines replace part of the manual production steps 3. Step 3 – Machines replace all the manual steps – producing defective products 4. Step 4 – JI DOKA - machines be come independent from workers – producing no

defective parts C. 3 elements of JIDOKA

1. Separation of workers from machines • Workers should be apart from machines so that they can operate several machines • Enabling workers to eliminate goods in process



2. Gadgets to produce no defects • JIDOKA machines • Test & Check machines and systems • ANDON: Visible control

3. Stopping lines • Assembly lines that stop when troubles occur • AB control

o A point-----------------------------------------------------B point o Material flows only when on A and not on B o The line stops when full works o Prevention of overproduction

• Right spot stopping o There is a time lag bet ween an alarming button and a m achine's stopping at a

set position o The time lag is a chan ce for process leaders to restore the machine. The line

does not stop

5. KANBAN – Control by eyes 5-1. Control by eyes

Components of KAIZEN (improvement) – excellent factory features: • Revealing problems and MUDA, and manifesting normal and abnormal situations • Solving problems at once on site • Regarding abnormality as needs of KAIZEN • Carrying out cotrol syst ems by eyes, and revealing MUDA and abn ormalities so that

anybody can see and understand them Visual controls Problems anybody can do = control by eyes = visible control

A. Red tag operation 5 S B. KANBAN plate operation Where, what, how many to put C. White lining 5 S D. Red lines 5 S, maximum volume of inventories E. KANBAN Pulling KANBAN

On the way KANBAN F. ANDON Workers' tools to inform process leaders of troubles G. Production control boards Displaying production progress. Fig 9. H. Standard operation

papers Walking lines, factory layout, operation orders visible at a glance

I. Gibbeted heads Pareto chart of defective products. Fig 4a, 4b. J. Error prevention boards Displaying errors occurred every hour

Self-controlling boards (JlSHUKANRI)



ANDON (paper light)

The function of ANDON is to inform process or line leaders of troubles. Kinds of ANDON



A. ANDON calling for parts. • Water spiders are in charge of delivering parts – Man with the trolley in fig. 6 • Hiring car system

1. A worker pushes a button calling for parts 2. ANDON on the line turns on 3. A water spider comes to the process 4. The spider gets an empty pallet and goes to a stock rack 5. The spider supplies the worker with the parts 6. The spider turns ANDON off

B. Abnormal ANDON

• For short assembly lines -- stewardess system 1. A trouble happens 2. A line worker pushes a button to call for 3. A yellow ANDON turns on 4. The line stops and a red ANDON turns on 5. A line leader or water spider comes to the spot

• For longer assembly lines (the one end cannot see the other) – hiring car system 1. While normal – green ANDON turning on 2. A trouble happens 3. A worker pushes a button and ANDON gets yellow 4. The line stops 5. A red ANDON turns on 6. A line leader or water spider comes to the spot



C. Functional ANDON 1. Machines operating well Green ANDON light 2. A trouble occurs – help needed Yellow ANDON light 3. Machine failure, tool e xchange,

line width change Red ANDON light

4. Over cycle time Red ANDON light 5. The trouble has been solved Green ANDON light

D. Progress ANDON

• Used in lines with longer tact time • A progress speed is segmented into 10 units corresponding to that of Andon • Limit switches detect progress units



E. Production control boards. • Placed at working sites to show how much a job has progressed every hour • Aiming that workers can sense progress by skin

5-2 KANBAN ordering system

A. Conventional ordering system and KANBAN system Conventional ordering system KANBAN system

• Information separated from material • Combined • Inventory control needed • Not needed • Invisible • Visible • Detached from a site • Attached • No kaizen needs • Kaizen needs comes out by

decreasing the number of kanban B. Production orders

• The conventional order is a pushing forward system. o Production plan o Parts deployment o Operation plan of processes o Operation order to processes o Production at each process no relation with others o Priority on the former process o Pushing forward o Forwarding material unnecessary for the next process



• KANBAN system o The latter process receives only necessary volume from the former one o Pulling system o The last pulling process is a customer

5-3. KANBAN functions

KANBAN is one of the tools of the LEAN system.

A. Autonomic nerves of LEAN • A KANBAN tells the former process what is going on at the latter one

o Information on necessary volume and operation instruction o Consumed quantity and kinds of parts. What, how and how many to make o Information on overprod uction. The former proc ess makes just the volu me the latte r

has taken away B. Improvement of a production site

• A KANBAN plate is always together with material – control by eyes. • Material is consumed first and information is generated next

o In which way a KANBAN is brought away o In which order a KANBAN is taken away o Workers can know progress and present conditions

• Improvement tool

o The number of KANBAN plates tells workers where to improve o How to reduce the number leads to improvements

5-4. Rules of KANBAN

1. The latter process takes what needed away from the former one 2. The former process produces what is taken away 3. The production should be leveled

o A production plan musy make kinds and volume of products even on each processes o Different from CRP (capacity requirement planning)

4. 100 % no defects 5. Real material display

o A KANBAN moves together with material o A KANBAN separated ~rom material is an instructive KANBAN

5-5. Kinds of KANBAN

KANBAN (a wider sense) A. Receipt KANBAN. Fig. 10.

• Subsidiary KANBAN o a line receives parts from a subsidiary

• Inter-process KANBAN. Fig 11. o plate KANBAN o box KANBAN o wagon KANBAN

B. On processing KANBAN

• a. KANBAN (a narrow sense)



o material in process. Fig 12.a. • b. Signal KANBAN

o production instruction about arrangement time.

5-6. Number of KANBAN

A procedure to decide the number of KANBAN. 1. Leveling of kinds and volumes of products 2. The number = daily number x (lead time+safety factor)/pallet capacity 3. Daily number = monthly production/operation days 4. Lead time = production lead time + KANBAN recovery lead time 5. Safety factor = days as close to zero as possible 6. Pallet capacity = as small as possible to enlarge delivery times.



6. Arrangement – preparation for machining

6-1. Improvement of arrangements

• Expenses of inventories are caused by many kinds of MUDA such as overproduction, goods in progress, transportation, keeping material at hands, defective products, etc.

• Expenses of goods in progress elongate a lead time. 6-2. Arrangement operations

1. Exchanging die molds and cutting blades 2. Altering standard operations – NC machines 3. Changing semi-finished material and components when a line gets a new kind of product 4. General preparatory works

6-3. Arrangement time

• Internal arrangement time -- time f rom the end of the present operatio n to the end of the next product. This is a time while a machine is not adding value on products.

• External arrangement time -- preparation and after cleaning while a machine is working. • The total arrangement time = internal + external time.

6-4. Improvement procedure of arrangement

• The internal arrangement needs to stop the machine. • The external arrangement should not stop the machine. • MUDA operation is looking for and waiting for something.

1. Establishment of arrangement improvement teams. 2. Analyzing arrangements operations – revealing. 3. Examining MUDA movements – 5 S. 4. Conversion of internal arrangements into external ones

o devices to stop no machines. 5. Improvements of internal arrangements

o boltless o cassette system o parallel arrangements

6. Improvements of external arrangements – 2 S. 6-5. Routines of arrangements.

Start from 5 S and finish in 5 S o The core is 2 S: SEIRI and SEITON

Searching MU DA Finding MUDA Using MUDA Carrying MUDA

• Throw away – Red tag operation • Display – Kanban operation • Put in order – Color operation • Fundamental arrangement

o Why you have to use that tool? o Discover a way not to use it

• Exclusive equipments – exclusive tools, wagons etc.



Do not move feet • Arrangement time parallels with stepping numbers

o Use exclusive equipments o Set switches as close to you as possible o Standardize by a parallel works

A bolt is your natural enemy o Try to exterminate bolts o Boltless – autocramp, cassette of cavitation o Eliminate a head of the bolt

A parallel operation o A few workers arrange a machine's front and rear side in parallel operation. o A careful plan is necessary.

Do not change a basic standard at all. o XYZ axis must be immobilized. o Make it unnecessary to adjust a position.

a center notch o Make it unnecessary to adjust a height

a spacer block Standardization

o A job incapable of being standardized can not be improved o Do not spend money for standardization o 3 GEN an d 3 SOKU principle: good products can not be made apart from

production sites 3 GEN:

1. GENJITU – Reality 2. GENBA: – On site 3. GENBUTSU – Real material

o 3 SORU: 1. SOKUJI – At once 2. SOKUZA – Without delay 3. SORUOU – Direct response

o Surface: – Reveal everything 6-6. Quality assurance

• How to avoid producing defective goods? o Stick to the standard operation o Produce items One by One o Firmly stop the line when a problem occurs o Perform fundamental improvements on site at once o Put quality into the product in the process

Levels of Quality Assurance

A. Defective products go out of a factory o The best solution is to close the factory

B. You try not to let defective products go out of the factory o Reinforce group inspections but MUDA remain o "Do not make claims even if making failures"

C. You try to reduce defective products o Information inspections o IE training o To try not to make defects from next time on



o Do’nt do it the next time D. You try not to let defective products go out of the processes

o Workers do their own self-inspections o Do not flow defectives, even if having made them

E. You try not to produce defective items o Zero defects o A defect is a result while a misstake is a cause . The result must be separated from

the cause o A worker may do a mistake, but shall not make any defective

Principles of no defects

• A defect becomes potential when a thing is produced and disclosed when used A. Do not make a product. – Make it as necessary as possible B. Make it from customer’s point of view

o Put the customer’s view into the production mechanism o POKA YOKE : Mistake Proofing o JIDOKA: Real automation o Standard Operation

C. Use products as soon as possible o An adept to find a defect is a Customer o Flowing production o Multi-processing

Structure of defects prevention

A. Man Company education Objective management Habituating to keep rules SHITSUKE – good manner Multi-processing Workers use their own products B. Information Controlling by eyes One defect is everything C. Material Stop separated inspection Original inspections and processing

must be combined

D. Machines POKAYOKE A machine possible to produce defects

must be automatically stopped A mechanism to make no defects All workers' participation in production

maintenance

My own machine can be served by myself

F. Method Use it as soon as produced Produce one by one Standard operation Everybody can do G. Zero defect 5 S SEIRI, SEITON, SEIKETSU, SEISO

SHITSUKE

lean production system whitepaper 4apr05 · 2018-11-11 · 2. principles of lean and 5 s 2-1 basic...

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