Unit 4_Part 1 CSE2001 Exception Handling and Function Template and Class Temp...
Timber finishes
1. TIMBER AS A NON STRUCTURAL MEMBER.
Timber is an organic hygroscopic and anisotropic material .It’s
thermal electrical acoustic properties make it very suitable to
use it as a non structural building material.
2. PROPERTIES OF TIMBER
Thermal Properties:
The coefficient of thermal conductivity of the timber is very low.
Specific heat of wood is high.
3. Acoustic Properties:
Timber it is ideal for sound absorption.
It is extensively used in concert halls.
AUDITORIUM, SYDNEY OPERA HOUSE.
4. Timber used to improve acoustics at soka university
concert hall.
9. TYPES OF TIMBER
HARDWOOD
Hard woods come from broad leaved
trees.These trees have flowers and
produce seeds such as nuts and fruit.
They are used for furniture making.
SOFTWOOD
Soft woods come from cone bearing
trees. Softwoods can be used for
furniture and doors but are mostly
used in construction for roof trusses
and stud partitions.
10. HARDWOOD
OAK: Oak is a heavy, strong, light colored hardwood. It is ring porous. oak
wood is commonly used for furniture making and flooring, timber frame
buildings, and veneer production.
WALNUT Walnut is strong, hard and durable, without being excessively heavy. It has
excellent woodworking qualities, and takes finishes well. The wood is light to dark
chocolate brown in color with a straight grain in the trunk.
11. ROSEWOOD : IT Very hard and has a dark reddish
brown color. It is fragrant and close grained.
TEAK :Teak is a yellow to dark brown hardwood which is extremely heavy,
strong and durable. It is used in the manufacture of outdoor furniture and
boat decks. It is also used for indoor flooring, countertops and as a veneer.
12. SOFTWOOD
PINE : Pine is a soft, white or pale yellow wood which is light weight, straight grained and
lacks figure. It resists shrinking and swelling .It is used in high-value carpentry items such
as furniture, window frames, paneling ,floors, and roofing,
SPRUCE: Strong and hard. Finishes well and has low resistance to decay.
Has moderate shrinkage and light in weight. It is used for construction
purposes in indoor use only (ex. indoor drywall framing)
13. REDWOOD : It is resistant to deterioration due to sunlight, moisture and
insects. It is used to craft outdoor furniture and decorative carvings.
FIR : Works easy and finishes well . Has low resistance to decay.
Used in furniture, doors, frames, windows, plywood, veneer.
14. BIRCH : Birch is a hard, heavy, close grained hardwood with a light brown or reddish
colored heartwood and cream or light sapwood. Even though it is a light wood ,birch is
strong and durable, meaning that it can be used to create a strong plywood.
CEDER : It is light and brittle it a popular wood for lining drawers, chests
and boxes. Simple cases and storage closets are also constructed from this.
15. APPLICATION
CLADDING : Cladding is the application of one material over another to provide a skin or
layer. In construction, cladding is used to provide a degree of thermal insulation and weather
resistance, and to improve the appearance of buildings.
Timber as a cladding is used in
1. External and internal wall
2. Flooring
3. Ceilings
18. Installing
horizontal
cladding
(existing
building).
• Batten size should be at least 2.0
times the thickness of the board.
• A cavity of at least 21mm shall be
incorporated into design to permit
air circulation and unrestricted
drainage of rainwater that
penetrates the cladding.
19. Fixing
horizontal
claddings.
• The boards could be used in a
simple overlap, feather edge
or square edged or as rebated
feather edge or shiplap.
• Generally battens to which
the boards are fixed should
be not less than
38mm×38mm.
BOARD STYLE OVERLAP EXPENSSION GAP THICKNESS
1. Feather Edge 25mm - 16-19mm
2. Rebated 15mm 3mm 16-19mm
3. Shiplap 15mm 3mm 16-19mm
4. Tongue & Grooved 10mm tongue 3mm 16-19mm
5. Solid square Edge 25mm - 16mm
20. INSTALLING
Vertical
Cladding
(new
build).
• Counter battens must be least
16mm thick.
• Cladding support battens should be
at least twice the thickness of an
individual board.
• A cavity of at least 21mm is required
to permit air circulation and
unrestricted drainage.
21. INSTALLING
Vertical
cladding
(Existing
Building).• Cladding battens and counter
battens over secondary
battens.
• To cladding battens fastened
directly to the outer wall
through the vapour barrier
using special fixings.
• To battens attached to a self
supporting treated timber
frame.
• Battens should be at 600mm
centres max.
• 400mm should be used for
diagonal cladding.
24. Advantages of timber cladding.
Its does not significantly increase the wall thickness because it
requires little space.
As a light weight form of construction, it imposes little
increased loading on existing walls.
It provides a wide range of visual option in the choice of
layout, profile, dimensions of boards.
It can be coated or left to weather naturally.
Installation is totally ‘dry process’.
25. CEILING FINISHES
The overhead interior surfaces or living of a room
Often concealing underside of the floor or roof above
It can construct either below pitch roof or flat roof and either horizontally follow the
pitch of the roof
•There are 3 system of ceiling finishes can be construct
⁃Exposed ceiling
⁃Fixed ceiling
⁃Suspended ceiling
38. WAYS OF FINISHING TIMBER
Finishing systems still follow the basic steps
required to achieve the desired result:
• Surface Preparation
• Staining (if desired)
• Filling (if desired)
• Finishing Proces
39. SANDING OF TIMBER is a critical process in wood
finishing to obtain a smooth finish. It enables the
finish to preserve and protect the wood, but also
enhances the beauty and grain pattern; features that
will influence the final appearance of the piece. For
the highest quality finish, all sanding dust must be
removed.
43. Dressing: To hide cracks and small holes, patch affected areas
with timber putty. Traditional lacquer based putty are ideal for
nail holes and fine cracks.
44. Filling: To achieve a fuller finish, often referred to
as choaking the timber grain, an application of
Woodgrain Filler is applied to the timber. Wipe filler
into the timber grain, then wipe off excess, allow to
dry thoroughly. Woodgrain Filler is compatible with the
desired finishing system prior to application
45. Shading And Toning : Shading or toning are used in
clear finishes after sealing to create intentional
contrast, correction of unwanted colour variations, or
to accent the wood grain. Toning is carried out using
either a transparent coloured sealer or a toning
lacquer as a haze coat before the final topcoat.
46. Topcoating The final protective film is the
topcoat. The system and topcoat used depend
greatly on the intended end-use of the article
47. SEALING OF TIMBER: To achieve a clear finish, the first step
is to apply a coat of transparent sealer. This seals the
whole surface and provides a smooth base for subsequent toning
and topcoats.
48. Linseed oil, a natural solution for Wood
Finishing
MATERIALS USED FOR FINISHINGTIMBER
49. Protection, maintenance and aesthetics
Easy to use, affordable and usually environmentally friendly (depending on the chosen brand and added components),
linseed oil is certainly a finishing product one has to try for the first time or to rediscover. Impregnating the wood to
saturation, linseed oil provides a golden hue, which will turn to amber over time.
50. Key features of linseed oil
I. Non-film forming (as opposed to varnishes)
II. Waterproof, elastic and wear-resistant finish
III. Satin finish
IV. Slight smell of grass
V. Deep penetration
VI. Golden to amber
VII. Affordable and ecological
VIII. Easy to use
IX. Easy care
X. Drying between 12 and 24 hours if polymerized and/or
drying agents are used.
XI. Enhances the beauty of the grain
XII. Dried by evaporation and oxidation
XIII. Compatible with most oils
51. Wax Finish
Sold in liquid, paste, and solid stick forms, waxes are formulated in a host
of colors.They will prevent it from oxidizing (turning gray) but don’t
particularly enhance the wood. In other words, once a coat of clear wax
dries on the wood, it will look like freshly cut, but unfinished, wood.
Beeswax is easily obtained and is easy to work with, particularly when it is warmed, but the benefits of using
this natural wax are outweighed by the fact that a beeswax finish isn't very protective and must be regularly
reapplied.
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52. Paraffins are also inexpensive waxes that come from petroleum sources, but they are more often used in candle-
making.
53. Additionally, once the wax is applied, no other current finish can be applied to the project to help protect the look of
the wax finish.Attempting to add lacquer, polyurethane or any other top coat to a wax finish is futile.
54. Shellac as a Woodworking Finish
The form of shellac used by woodworkers as a finish is formed by dissolving flakes of shellac in an
alcohol solvent.This shellac and alcohol mixture is then applied to the workpiece by the use of a
rag.
Shellac is somewhat outdated or obsolete when compared to most other modern finishes, as it
provides only minimal protection. It is, however, a very useful primer finish since many other
finishes bond very well with it.
55. Advantages
As long as the surface bearing the shellac has not been damaged, shellac provides the following benefits:
Water resistant
Resistant to alcohol
Excellent as a primer coat, to seal and prevent the bleeding of resin or pigments, and to prevent wood
stains from blotching
Can be applied under most other finishes. Note that polyurethanes have trouble adhering properly due
to natural shellac's wax content. Simply use de-waxed shellac to prevent these problems.
Easy to repair
Easy to apply (brush, rag, or spray on, thin cuts easiest)
Easy to re-apply if the original finish becomes worn or damaged
Non-toxic and food-safe (Use appropriate solvent)
User can control how quickly product is built-up by adjusting dissolved shellac concentration
Cold temperature application – Unlike other finishes, shellac can be applied in cold temperatures (5
°C/40° F and below) without concern over proper drying and curing
Non-yellowing and non-darkening as it ages
56.
57. Varnish
Varnish is a transparent, hard, protective finish or film that is primarily used in wood finishing but also for
other materials.Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent.Varnish
finishes are usually glossy but may be designed to produce satin or semi-gloss sheens by the addition of
"flatting" agents.Varnish has little or no color, is transparent, and has no added pigment, as opposed
to paints or wood stains, which contain pigment and generally range from opaque to translucent.Varnishes
are also applied over wood stains as a final step to achieve a film for gloss and protection.
After being applied, the film-forming substances in varnishes either harden directly, as soon as the solvent has
fully evaporated, or harden after evaporation of the solvent through curing processes, primarily chemical
reaction between oils and oxygen from the air (autoxidation) and chemical reactions between components of
the varnish.
59. Polyurethane
Polyurethane varnishes are typically hard, abrasion-resistant, and durable coatings.They are popular
for hardwood floors but are considered by some wood finishers to be difficult or unsuitable for finishing furniture or
other detailed pieces. Polyurethanes are comparable in hardness to certain alkyds but generally form a tougher film.
Compared to simple oil or shellac varnishes, polyurethane varnish forms a harder, decidedly tougher and more
waterproof film.
A table green wood-stained and varnished
with three layers of polyurethane varnish
60. •Lacquer is a clear or coloured varnish that dries by solvent evaporation and often a curing process as well that
produces a hard, durable finish, in any sheen level from ultra matte to high gloss and that can be further polished as
required.
62. Different Types of Preservatives for
Timber
- Boron
- Borax
- Captafol/Chlorothalanil/Timbafol
Solignum paints
Creosote oil
- Creosote
- NAPCP
- CCA
- CCB/CCF
- CC
- AAC
- CU-HDO
- Methylen-bis-Thiocyanate
63. WHY DOES TIMBER NEED TO BE FINISHED?
Prevents the accumulation of dirt , slow down the exchange of moisture between the wood and
the air and accentuates the features. It can be used to change the color of the timber
