2. Coconut timber
• Wide, unbranched,
cylindrical shaped stem.
• surrounded by a narrow
cortex.
• Average diameter-23cm
• Non-homogenous raw
material.
• Principally, density
decreases towards the
inner of the stem, and
over stem height.
2
3. Why coconut?
• Strong and flexible.
• Common and familiar
building material.
• Not a forest tree.
• Minimum defects (Knots,
splits….)
• Low price.
• Durability.
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6. Log supply.
Log supply to the industry will be done
in two channels.
1. From local tree fellers.
• Company representatives for their
village/region.
• Competitive price.
• Only first logs and middle logs.
2. By own logging team.
• Chainsaws.
• Felling and transporting to the mill.
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7. Log supply.
• First logs, Middle logs and third logs will be
marked using a color code at the point
where logs are cross cutting.
• Log loading & unloading will be done
manually.
First Log - Red Middle Log - Blue Third Log - Black
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8. Sawing.
The logs can be broken
down by,
• Splitting
• Hand-sawing
• Chain-sawing
• Circular sawing
• Band-sawing
• Frame-sawing
-Rafters, Beams
-Ceiling panels
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9. Chain-sawing.
• To make rafters and beams.
• The production rate is about 0.04 m3/man-hour.
• A recovery of about 45 % can be achieved.
Cutting pattern for beams Cutting pattern for Rafters
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11. Chain-sawing.
Advantages Disadvantages
• Low initial cost • Frequent re-sharpening of
the chain.
• Portability • Wide saw kerf.
• Less labours
• Moderate production rate
• Suitable with the required
cutting pattern
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12. Band-sawing.
• For sawing Ceiling panels.
• Using low and medium density timber.
• The feed speeds,
-Breaking down the logs range from 10-25m/min
- Edging or re-sawing feed speeds of 20-40 m/min
• Minimum wastage & suitability with required
cutting pattern.
12
14. Band-saw.
Wood Mizer LT10 band saw.
• Log capacity - 70cm x 5.4m
• Power - 5.5kW electric
• Price - Rs. 950,000
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15. Dip-treatment.
• Just after sawing process.
• In order to prevent any attack of fungi, mould or
insects during drying.
• A dip treatment previous to stacking is
necessary.
• 1% solution of Methylen-bis-Thiocyanate.
• The dipping tank - welding half-cut oil drums.
15
16. Seasoning.
Reduces the presence of water in the wood
Thus reduces the danger of movement.
It also reduces the danger of fungal attack
and improves the mechanical properties of
the wood.
Coconut palm wood has an initial moisture
content ranging from 60 % (high density) up
to 230 % (low density).
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17. Seasoning – Air drying.
stack it off the ground
Between the stacked
layers of boards, stickers
have to be placed to allow
ventilation of the stack.
All stickers should be of
the same size and should
have been treated before
use.
Apply weight on top. 17
18. Seasoning – Air drying.
Time consuming.
-Low density timber –13-16 weeks
-High density timber – More than 26 weeks
It is recommended to air-dry the lumber to
fiber saturation point before kiln drying.
For coconut wood 24 %.
Equilibrium moisture content - 12 to 18%.
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20. Seasoning – Solar kiln.
•Glass house type solar kiln.
•Chamber with glass roof and walls.
•The sunrays heat up the air in the kiln
directly.
•No specific kiln schedule will be used.
•Shorten the drying time.
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21. Preservation.
•Class II timber(STC classification).
•Boron treatment.
•Usually applied as salt (Boric Acid,
Borax)
•Applied in the diffusion process.
•Dipping tank - welding half-cut oil
drums.
•Heat source – soft coconut firewood. 21
22. Boron treatment.
• The sawn timber is dipped into a 20% solution of boron
heated up to a temperature of 40’C.
• The immersion time should last at least 20 minutes.
• The timber is stacked closely and covered with
polyethylene sheets in order to facilitate the diffusion.
• The storage time - at least 6 weeks.
• After this period an overall retention of boron is about
3 %.
(Palomar, 1986)
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29. References.
• Coconut palm stem processing technical handbook, Wulf Killman,
Dieter Fink, (1996) Dept. Furniture and Wooden Products, Federal
Republic of Germany
• Bailleres H, Hopewell G, House S, Redman A, Francis L, and
Ferhrmann, J (2010). Cocowood processing manual. From coconut
wood to quality floring. Department of Employment, Economic
Development and Innovation, Brisbane.
• Ruwanpathirana, N.D, (2008)Timber Utilization in Sri Lanka.
• Ariyadasa,K.P, Assessment of tree resources in the home gardens of
Sri Lanka.
• Structural and mechanical properties of the wood from coconut
palms, oil palms and date palms, vorgelegt von,Leila Fathi (2014)
Univrsity of Hamberg.
• A Planning Guide for Small and Medium Size Wood Products
Companies, Second Edition, Jeff Howe, Steve Bratkovich (2005) ,
USDA, available at http://www.fpl.fs.fed.us/documnts/misc/natp0995.pdf
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