Post 647 -by Gautam Shah


Natural and Industrially-produced materials require some form of surface modifications or treatments, before being put to functional use, or for readying them for the next process. Surface modification at a basic stage, consist of cleaning and mechanical scrubbing. The surface modifications are for creating use-worthiness by levelling, texturizing, or for application of additional materials for shielding. The surface modification starts with visual observation and touch-feel experience that no foreign materials have remained on the surface, and all loose (removable) materials are removed. These simple processes ensure integrity of the surface.


The next level of surface modifications are applications like coating, physical-chemical treatments, cladding, mounting, plating, joining, welding, levelling, cleaning, washing, ph balancing, static removal, etc. Surface modifications are intently surface preparation processes and may impart radically different surface qualities such as textures, ionization, etc.


At another level Surfaces Modifications are not attempted, but such situations are negotiated with technologies. These include defining means to override the hindrances of texture, handling issues, electrical and other properties. These technologies also include forming shields around the users, tools and other equipments rather then over objects. The shields are physical layers and non-physical arrangements like restricting the exposure through time-space management.


In early ages, the surface modification and applications were an integrated process for exploiting the surface of any object. Primitive arts and crafts had a comprehensive treatment that consisted of 1: Modification of the surface, 2: Application of surface forming materials, and 3: Rendering new textures and tonal variations or shades. At a later stage an additional treatments for protection of the new surface were devised.


Surface modifications are physical, chemical and mechanical processes.

The Physical processes are mainly used to remove unwanted particles or materials (such as rust, nodules, residual deposits, dust or grease, lubricants, cutting-oils, etc.) adhering to the surface. Rubbing, air-dusting, vacuum cleaning, wiping, water-bathing, etc. remove such adhered materials. The particles have remained on the surface due to the holding by surface texture, bonding or ion attraction, and horizontal storage. Washing with soap or a surface active agent (surfactant) can weaken the ion attraction break the weak molecular bond generate by-products that can be removed easily.


The Chemical processes include acid-alkali treatments and solvent washing. The processes roughen, etch or smoothen the surface. In many instances the resultant by-product is beneficial or neutral, and so allowed to remain on the surface. In other instances a secondary treatment is required just to remove the by-products of the first treatment. Sometimes Surface preparation agents themselves are the primary surface finishes. Such agents cover the surface area as an intermediary film. Such films help in bonding of the final surface finish. Chemical processes also include burnishing, flame-treatments, surface annealing and hardening, cathodic modification, sputtering and material’s depositions.640px-A_brass_utensil

The Mechanical Processes affect the surface superficially. Cleaning of the surface by removal processes include abrading, grinding, rubbing, blasting, planning, chipping, etc. Other mechanical processes alter the surface with newer textures by engraving, patterning, planning, surface deformation, etc.


Surface modifications processes have been used for body painting, pottery, home building, agriculture, mural or wall artwork, adornments, jewellery, ornamentation, household utilities, tools, musical instruments, etc. Surface modifications were explored pattern making, texture creation, personalization, cultural expression, totem, abstract or symbolic representation etc.


Surface levelling is achieved by scrubbing or rubbing off the impurities, removing select protruding sections, or by skinning the entire surface area. In later cases there are chances of removing a seasoned or matured face and exposing a fresh one. Partial scrapping of the surface creates qualitatively unequal zones. This is the reason why over the ages levelling ‘plasters’ have been preferred. The ‘plasters’ can be thin coating, or an application of thicker mass. These were often rendered with patterns and textures or ‘loaded’ with minerals and colourants. Wet surfaces were, either, engraved or embossed with patterns to encourage the penetration of colours, to produce a bas or relief effect, or provide a highlighting boundary to the drawn object. Colours were blown as dry powders or applied as pastes and dabbed (pressed) into the wet plaster.

Gesso, a mixture of plaster of Paris (or gypsum) with size, is the traditional ground. The first layer is of gesso -grosso, a mixture of coarse, un-slaked plaster and size. This provides a rough, absorbent surface for ten or more thin coats of gesso sotile, a smooth mixture of size and fine plaster previously slaked in water to retard drying. This labourious preparation, however, results in an opaque, brilliant white, light-reflecting surface, similar in texture to hard, flat icing sugar.

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Post 646 –by Gautam Shah


Paper is a sheet form of material, and substantially used in sheet-form. Paper’s chief raw material is cellulosic pulp. It is also used in ‘non-planer’ forms, such as moulded products (egg crates), packing cases (glass), mould dummies, and as Papier-mâché.

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Paper pulp egg Cartons Wikipedia Image by Edward Betts

Paper as a sheet material is available with many different properties. It can be rough, smooth, grease-proof, water absorbent, water repellent or resistant, soft as cotton, stiff as board, heat resistant, fireproof, combustible, chemically resistant opaque, translucent, transparent, coloured, glossy, dull, strong, weak, tear-able, non-tear-able, light heavy, pulp-able cellular, waxed, sanded, embossed hinged corrugated, easily folded and pierced, coarse, fine or flocked.

Paper is mainly used for writing, printing, drawing, painting signs and images. Paper has many functional uses like wrapping, filtering, absorbing, insulating, protecting (Thai umbrellas), cleaning, mopping, polishing, buffing, toys and product forming, mould making, engraving, etching, embossing, medicare dressing, garment making, and for glazing (Shoji for windows and Fusuma for room dividers). Other uses include mask making, light canoe or boat making for races, single-use construction forms, casting die dummies, kites, lanterns carnival floats, tubes, textile bobbins and cones.

Pen_box,_signed_by_Mohammad-e_Ebrahim,_Iran,_1694_AG D,_papier_mache,_oil_paint_-_Aga_Khan_Museum_-_Toronto,_Canada_-_DSC07051

Pen box of Papier Mache with Oil coating Iran 1694 (Now in AK Museum Canada)

Paper pulp is used in various sheet form composites. Fiber boards are products engineered at a pulp stage. Various products differ in terms of nature and level of ‘pulping’, pressing technologies (pressure, temperature, curing used), wet or dry process of manufacturing, additives (both filler and bonding) and surface treatments. The products include high-medium-low density boards (typically MDF), hardboard, ‘Masonite’ boards, pulp boards with gypsum, cement and other minerals, natural and synthetic fibre additives. These sheet materials are surface treated, coated, tempered, laminated, co-formed or co-extruded.


Parchment Paper > Pixabay image by Geralt

Inferior plant materials and timber wastes are partly pulped to form a homogeneous mass. Such partly pulped mass, however lack the mutual particle bonding. Boards (and often pre-shaped forms) are created by steam-pressing and with aid of 5% bonding materials (typically Urea or Phenol formaldehyde). Portland cement, Gypsum and polymer emulsion adhesives are also used for forming building boards. Paper pulp boards of extreme light mass are coated with Gypsum, polymers and foam to form acoustic ceiling panels. Layered paper composites with phenolic compounds are used as circuit boards and electric insulation panels.

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Paper making in Hahnemuhle > Wikipedia image by Hahnemuhle PR 


Structure of paper as sheet material differs from other sheet materials:

  1. Papers unlike plastic films and metal films are fibrous.
  2. Paper is composed of single short fibres, arranged largely at random instead of a regular array as is the case with woven fabrics.
  3. Unlike cloth, felt or leather it is laminar, that is each fibre is disposed mainly in the plane of the sheet.

Paper, however, resembles other sheet materials in that its structure is anisotropic in its plane and most of the fibres are oriented along the grain or the machine direction.

Paper is mostly made from cellulosic fibres derived from plant sources. The fibres depending on their origin have different types of cell structures, and so provide unique character to the paper. Cellulosic fibres are hygroscopic and swell considerably when wetted, but retain strength and durability. Most plant materials also contain non-fibrous elements or cells. These are less desirable for the paper making, but are useful as a filler material. Until about 19 C. paper was produced by hand processes, and as a result had very distinctive local style, texture and properties. Through the 18th C the paper making process remained essentially unchanged. The linen and cotton rags were the basic raw materials, but increasing demand for paper was posing shortage of pulp raw materials.

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Packaging forms with Papier Mache > Wikipedia images by Berklas

Paper is manufactured from material resources that can be regenerated, and the product is a recyclable material. Major sources of cellulosic fibres for paper manufacturing are wood and cotton. Cotton fibres are used in the form of lints (seed hair left behind after ginning), staples, waste yarn and threads and rags. Lints require no processing, staples need length shortening, but yarns, threads and rags need undoing of all mechanical processes such as spinning and weaving. Cotton fibres offer strength, durability, permanence, fine formation, colour, texture, and feel.

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Modular ceiling Panels of Paper Pulp > Wikipedia image by Adamantios

Wood pulp has been the chief material for paper making, but where forest resources were scant, many alternative sources have been explored. These sources include: Cereal straws, plant stems, linen, jute, hemp, bamboo, cane (rattan), paddy (rice) straws, banana leaf, sugar cane waste bagasse and grasses like esparto. Paper made from such alternative pulps, and without an admixture of other fibre tend to be dense and stiff, with low tear resistance and low opacity. Often such fibres are desired as additives for producing paper for abrasives (sand-paper), cover stock and heavy-duty industrial papers. Such fibres are also used for strength in duplicating and manifold papers. Flax is grown expressly for high-grade cigarette paper.


Synthetics: Paper like sheets > ( Image by AlexanderStein

Synthetic or man-made fibres provide certain advantage when compared to plant based materials for paper pulp. Natural cellulose fibres vary considerably in size and shape, whereas synthetic fibres can be made uniform and of selected length and diameter. Long fibres, for example, are necessary in producing strong, durable papers. There are limitations, however, to the length of synthetic fibres that may be formed from suspension in water because of their tendency to tangle and to rope together. Even so, papers have been made experimentally with fibres several times longer than those typical of wood pulp, and these papers have improved strength and softness properties. Natural cellulose fibres have limited resistance to chemical attack and exposure to heat. For such purposes synthetic fibre papers can be made resistant to strong acids, for example in chemical filtration. Paper can even be made from glass fibre, and such paper have great resistance to both the heat and chemicals.

Golfing Tee Golf Golfer

Golf ball rest pins of dissoluble wood Pulp (

Rags (mainly of cotton) are used extensively where permanence is of prime importance such as for bank notes, legal documents and security certificates. Technical papers include tracing papers, vellums, and reproduction papers, high-grade bond letterheads, cigarettes, carbon, and Bible papers. Khadi (Indian hand made) paper is an example of high rag content paper.

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Rags sorting for paper making > Image by Lewis Hine (1874-1940)

Wastepaper is a major source for cellulose. By recycling the wastepaper the dependency for virgin fibre is reduced and the problem of solid waste disposal is minimized. However the difficulties like, gathering wastepaper from scattered sources, sorting mixed papers, and recovering the fibre from many types of coated and treated papers, make it a very complex problem. Waste Paper treatments for asphalt, synthetic adhesives, metal foils, plastic and cellulose-derivative films and coatings, printing inks, etc. pose acute problems in reuse of paper wastes. Wastepaper is of four main categories: High-grade, old corrugated boxes, printed news papers, and mixed paper. High-grades and corrugated stocks originate mainly in mercantile and industrial establishments. White paper wastes accumulate in paper conversion units and printing plants. Magazine stock comes from newsstand returns, but some comes from homes. Mixed papers come from collectors. Grey Board, cardboard or Packing carton papers are produced from recycled paper wastes. These are as single or multiply boards.

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Laminated-multi-layered paper products > Wikipedia image by from USA

In recent years Papers have been coated, layered or co-extruded with many other forms of sheets, films and membranes. These include, metal foils, polymer films, metalized polymer films, films formed through liquid coatings, in-situ foam forming.




Post 640 –by Gautam Shah


Objects and Surfaces have their demands, which must be tackled before one can use them. Objects are used for their dimensional features, mass, form, engineering attributes, and other consecrations like cost, availability, ecology, etc. whereas the surfaces are used for sensorial purposes. Objects and Surfaces are rationalized to prepare them for technical use, handling, environment and assembly.


Stone Wall > Pixabay Image by GregMontani Bayern

We do so by matching the requirements with readily available lots. However, we need to prepare, process or manufacture the objects or surfaces through several conversions. The processes of rationalizing, though begin with the object-modification, may eventually include changing the environment. Changing the environment immediately can bear upon a very vast field of actions. Like the old fable, for the king it is more efficient to cover own feet with leather shoes than layer streets of town, to protect from dirt’. ‘Similarly one may open the umbrella during the rain and not at other times’. It is more efficient to deal with the environment in space and time.


The Parthenon -West side Weathering and usage > Wikipedia image by Yair Haklai


Positional or differential weathering > Keshav Temple in Somanthpuram India  > Wikipedia image by Hemanth M Y

The time and effort expended in modifying the entity or its environment, is not very efficient. It is often more effective to compose a new entity (functionally, technologically and economically), than expend too much effort in improvising it. It is better to buy a new razor blade with a sharp edge, than polish the blunt one, or join a bone mechanically, than allow passage of time to do so.


Tennis Balls – Multi material objects > Pexels image by

Objects and the surface systems, if of single material, the operative demands are simpler, but if composed of many materials (similar or dissimilar), have complex and often in-specifiable demands. It is ideal to reform the object entity by integrating its surface systems with it. Where such one-to-one integration is not possible, the object entity and its surface system both may be individually refashioned to become each a single material entity.


Diverse and Multi layered treatment of windows > Pexels image by

A surface system can be facilitated by delaying or curtailing the effects of environment, for the functional period of the entity. Environmental effects are from specific orientation and for duration, and so a surface systems can be designed to be selectively local or dynamic. Liquids and gases have no stable object boundary, so must be contained, and for such material phases the container becomes the apparent surface system.


Nuclear waste Storage > Wikipedia image by Bill Ebbesen

Ordinarily surface finishes are fashioned, only after the object and its relevant environment have been conceived. But sometimes an object could be so hazardous that until a really workable surface system is designed, the object cannot be allowed to exist or function. Similarly an environment could be so harmful that till an appropriate finish system is devised the object cannot exist, much less function in it.

The environment influences objects in such a complex way, that any search for logic is sometimes impossible. This is the reason why many surface makers seem to work with their intuitive faculties. To some people, ‘providing a surface system is an art or craft, rather than a scientific discipline’.


Car assembly and finishing is a single process > Pexels image by Mike

At any cross section of time, we find a large number of surface systems are overtly attached to the object or in the process of being integrated to the entity-base. It is very necessary that a surface system in such a situation, be singular in constitution or at least be effective in that manner. Finish makers aspire to provide a singular surface system in place of a multi-component system. However, in a finish maker’s world there are very few situations where singular surface system can satisfy all the demands. Multi-component surface systems are reality.


Installation of base for MUGA tennis court > Flickr image > credits >



Post 638 –by Gautam Shah


Many materials, even if suitable for their engineering performance do not have an appropriate surface system, nor are they amenable to modifications towards such needs. Large number of objects that we use to day have applied surface systems. Applied surface systems consist of foreign materials, generically, either of same type, or of different constitution.


Adhesives, Gums, Glues > Wikipedia image by Mr Brian

There are many methods of applying surface systems to base objects. Some surface systems stay in place due to gravity, whereas others may require some degree of fastening, achieved by mechanical fixing, adhesion, chemical reaction, ion attraction, etc. Many surface system use combination fixing, i.e. one method to achieve initial anchorage, and another for ultimate fixing. In some instances one system of fixing is operative for normal circumstances, and another one is provisioned for extra ordinary stress conditions.


Fixing Tiles on Walls > Pexels image by Victor Zissou

Fixing of a surface system: Fixing makes the applied surface system operate in consonance with the entity. The space between the surface system and the entity is reduced or eliminated by very close packing, or by introducing an intermediary element. Adhered surface system, cover the object interactively. Adhered surface systems nearly merge with the base entity, and as a result the transfer of stresses is evenly distributed. Adhesives do not form localized stress points like screws and nuts do. For this reason adhered surface systems could be much thinner, than the body necessary for mechanical fixing. A thin body surface system has greater flexibility, ductility, and stretchability, and so better unified behaviour with the base entity.


Wood Glue > Pixabay image by Counselling Ulrike Mai Cape Town SA

Adhesives can join substances that are materially and dimensionally different and form-wise very difficult. Adhesive joints may be designed as required, to be elastic or rigid. Relatively low process temperature involved in adhesive bonding does not affect the crystallographic structure of the metal. Adhesives can create very extensive, multi layered laminar compositions without physically cutting or puncturing the materials.


Wikipedia image by Coyau

Limitations of adhesives are few but important. Adhesives require elaborate surface treatments, specific application conditions, curing procedures and considerable expense of time for setting. Inspection of the joint is difficult. Joint design becomes very critical compared with other mechanical and thermal processes. The adhesive itself may corrode the materials it is joining, or induce stresses during curing.

  1. A very strong adhesive will not allow a joint to open out, so there is a rupture elsewhere in the material.
  2. Too weak an adhesive fails and separates into two distinct layers.
  3. An adhesive may fail to adhere to one face

With correctly prepared surfaces, the adhesion at the interface is usually greater than the strength of the adhesive itself, and failures occur within the adhesive film. Failure of the adhesive film is usually caused by the propagation of cracks accelerated by the presence of discontinuities and flaws. Therefore, thin layered adhesives provide the strongest joints. Usually the adhesive selected should have similar strength characteristics to be adherends being bonded together. An exception would be where boding is only temporary pending another joining processes to be used. Most adhesives show optimum strength characteristics when in tension or compression closely followed by, shear. Often the high strength, thermosetting adhesives form brittle bonds that are adversely affected by vibration and impact loading, causing the bond to crack or shatter. Under such conditions a slightly weaker but more resilient adhesives may perform more satisfactorily. Adhesives may show a satisfactory strength characteristic under test conditions, but will tend to creep under sustained loads in service.


Fixing chips > Pixabay image (Time to glue chips) Pixabay image by Windell Oskay

Adhered finishes often require an intermediary agent, the adherent, to achieve the bonding. The adherents have a dual or multilateral qualities, capable of adhering to the singular or multiple components of both, the surface system and the base entity. The adhesion is provided by surface tension, ionic attraction, friction and chemical bonding. Adhered finishes are occasionally removable but not easily demountable and relocatable. Adhered finishes also have size limitations. The joints in adhered, finishes occur as a thin divide between the two surface components, or as lap-over with a seam joint (stitched, folded, fused).

Adhered finishes, due to their simplistic technology can be employed on remote locations. The surface components are sometimes designed to have different personalities on the outside and the face to be attached to the base.


Silicone Caulking > Wikipedia image by Achim Hering

Adhesives are used for joining a wide variety of similar and dissimilar materials such as: paper, wood, leather, glass, fabrics, ceramics, plastics, rubbers and metals. However, the largest sectors for adhesives are masonry structures, where large variety of cementing materials like, clays, Portland cement, lime, plaster of Paris (gypsum plasters), etc. are used. Another field akin to adhesives is of sealants, putties, mastic compounds, waterproofing agents, noise dampening coatings. Structural adhesives are expected to provide structural properties equal or often better than the materials being joined. Adhesives perform many other functions. Silicone and polysulfide rubber are used for dampening vibration (glass to window frames). Aircraft and automobile frame components are bonded by adhesives to save labour, weight, and expense of rivets like fasteners. Components joined with an adhesive cannot be separated but some demountable adhesives are available.


Other Blogs on related topics









Post 637 –by Gautam Shah

This is a random selection of BLOGS on Design Practice (Professional Practice) from several of my blogs on the subject.


Flickr Image by Denis Jacquerye


  • CLIENT and DESIGN PROFESSIONAL -Relationship >>






  • Differentiating COST from VALUE -Interior Design Practice >>




  • INTERIOR DESIGNER – the role



  • MANAGING FEES -for Building Design practices PART – III

  • MANAGING FEES -for Building Design practices PART – IV

  • MANAGING FEES -for Building Design practices PART – II

  • MANAGING FEES -for Building Design practices PART – I








Pexels Image by Kaboompics // Karolina >

A set of articles on DESIGN IMPLEMENTATION PROCESSES that were offered as PG Level course are also available at >


01 Organizations

02 Essentials of Design Organizations

03 Design Organizations

04 Projects of Design

05 Job or Assignment Handling in Design Organizations

06 Deliverables from Design Organizations

07 Dealing with a Client in a Design Organization

08 Specifications

09 History of Specifications

10 Standards

11 Liabilities

12 Bureau of Indian Standards BIS

13 International Standards Organization ISO

14 ISO 9000 and other Management Standards

15 Quality for Designers

16 Quality Conscience

17 Consumerism

18 Human Resources

19 Leadership in Design Organizations

20 Data, Information and Knowledge

21 Design Processes 21-1 to 21-4

22 Decision Making and Problem Solving

23 Systems Thinking

24 Risk Management

25 Guarantees and Warranties

26 Finance



Post 636 –by Gautam Shah



We are more concerned with the width and height of openings. Width and Height are primarily functional derivative, and secondarily a matter of proportioning. The proportioning works intrinsically with width versus height, but more importantly with the schema of the building. The schema also takes of aura or grandeur of the openings like doors, gates, etc. Over engagement with width and height of openings can be reduced by use of surrogate like shadows (Sciography from Greek σκιά ‘shadow’) and through scaled replicas or models. The former technique creates a metaphoric depth of very high contrasts. The later one creates a realistic version but often too small for the vision cone of the eye. In the first case the contrast is between black and white (or presence and absence of certain colour), where the models are visualized in design offices far away from the realities of local climate and terrain. The sciography and the models do not fully show the subduing effects of reflections from surroundings or floors, or counter balancing by internal illumination.


The openings gain a third dimension due to the shadows, and shadows occur due to differences in depths. But depth of a door or window regulates the field of view and amount of illumination. It governs the changes occurring in transit through the opening. These include disciplining the passage of goods and people. Depth forms an intervening space and time for mechanisms like filtration, funneling, release, mixing, direction, etc. of air and illumination.


The depth of an opening derives from the structures like walls, partitions, domes, etc. but in few cases it is achieved through architectural manipulation. External walls of the buildings, till about the Gothic period, were heavy offering two choices for showing the depth on the external face or internal side. Both of these were done in several ways. A chamferred edge on outside, enlarges the size of the opening, view of outside worlds, net illumination gain for the interior and weather protection. A chamferred edge on inside cut the glare, diffused the illumination, reduced the wall surface requiring mural or other treatments.

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Gothic buildings’ thinner walls, however, did not allow such a play. So instead the Windows were elaborately segmented. The mullions, muntins and traceries did not divide the story line running through. Gothic glass unlike modern glass was opaque so did not allow interiors to be visible, but during daytime the segments and colours both compensated lack of wall murals and mosaics (of an earlier era). The third dimension of the opening was completely eliminated with glass curtain wall buildings. Mies van der Rohe was yet criticized for using very emphatic mullions.


The Depth of openings enhanced the dual character of inside and outside. The architectural depths of the openings are, however, changed by bevelled edges, chamferred sides, introduction of pilasters, intrados, extrados, sloped sills and opening heads. A bottom taper brings the light to the floor, and a sloped interior head illuminates the ceiling.


One of the most fascinating aspects of openings is the threshold. It may be informal, just a marked significance by small change of elevation, colour or texture. The greater depth of the opening bestows a formal change of a domain, due to marked elevation, changes of treatments and side treatments like seating place, alcoves and chambers. A threshold has two distinct worlds on either of the sides, one or both of which could be real or notional. Such elaborated depths of the door elements become resting zones, zone for transition, point of decision making, celebration, welcome or separation.



BLOG LINKS on -Kitchens -Foods -Cooking Spaces

Post 635 –by Gautam Shah














FOOD PREPARATION SYSTEMS – II Kitchen and its place in the house

FOOD PREPARATION SYSTEMS – III Kitchen and evolution of its Facilities



FOOD PREPARATION SYSTEMS – VI -Kitchen Design by Fires

FOOD PREPARATION SYSTEMS – VII -Kitchen facilities and tasks






SPACE PLANNING -Developments