Ideal Properties of a High Quality Cutting Board, Coursework Example

The Scratching Hardness, Impermeability and Water Absorption of Oak, Beech, Sapele, Ash and Chestnut and a Comparison of their Properties against the Ideal Properties of a High Quality Cutting Board

The objective of this experiment is to define the capacities of impermeability and hardness. The perspectives of Williams(1987) and Legner (2014) will be reviewed. The qualities of wood which are the texture, vessels, grain angle, early wood or late wood, sapwood, heartwood, growth rate and density are varying aspects with the species of wood. The distinct types of timber Oak, Beech, Sapele, Ash and Chestnut have distinct qualities which will be assessed in comparison to the requisites for a high quality cutting board.

There are more than 18,000 distinct species of wood, however only 50 species of timber are applied in commercial construction in Canada and the United States.  Considering the 50 species of wood which are applied in commercial construction, only five are native to North America, Japan, Europe and the tropical areas. Notwithstanding, if no one were able to comprehend the distinct qualities of the manner by which the environmental aspects, finish and hardness interact, it would not be feasible to approximate the production for the majority of wood species (Legner 1).

The production of the wood is reliant on selecting the correct treatment process. This is conducted as a function of the application of the wood, the conditions and the treatment processes which will be applied.  In order to obtain an extended service use, it is best to select wood species and treatments which are suited for the conditions in which they are implemented. Climates which experience various changes in weather exert more significant stress on the wood treatments than the wood species which are applied in climates which are temperate (Williamss 16- 2).

Wood is a material which is composed of hetero generous tissues. The tissues within the wood species are composed of distinct aspects of cells. There are cells with the tissues of the wood species which serve as mediums of conduction and others which serve as mechanical support. In the wood species which are designated gynosperm, these operations take place in the cells which are recognized as tracheid. There is a separation of labor which exists in the cellular tissues of the wood species. The various types of wood which compose the woody tissue are applied for mechanical support. The vessels are the types of wood cells which conduct fluid throughout the wood species (Legner 1).

Wood species have distinct mechanical properties. These properties perform in conjunction with other aspects of the wood. The mechanical characteristics of the wood enable the wood to resist certain tensions and pressures, which would cause changes in its form and cause the wood to develop deformities. These forces are detailed as the stresses which are presented in the wood species. In the circumstance of the stresses being in excess of the forces of cohesion of the wood species, a failure will occur. The permeability of the wood is directly related with its stiffness (Williams 16-2).

The aspect of impermeability is correlated with stiffness. The reduction in the wood content of hygroscopic water causes a diminishing of the dimensions of the wood. This is attributed to the shrinkage of the wood cells. As the hygroscopic water in the wood is evacuated through evaporation, the wood shrinks. As the woods experiences shrinkage, the cells within the wood tissue become more compacted and the fibers acquire a greater tolerance for stress.  One of the drawbacks in the application of wood is the aspect of shrinkage which occurs as the hygroscopic water is eliminated. The permeability is an aspect of the water content of the wood. Wood species which have less water content are more impermeable which is correlated with a higher level of stiffness (Legner 1; Williams 16-3).

The species of wood is the main aspect which determines the properties which are contained by the surface of the wood. These characteristics influence the performance and the adhesion of treatments. The anatomy of the wood is the determining factor for the wood species having the attributes of softwood or hardwood. The specific gravity of the wood or its aspect of hardness is not the determining factor. The performance of the treatments which are applied to the wood species is influenced by the following factors:

1. Specific gravity.
2. The density of the LW rings.
3. The placement and the number of the ray cells.
4. The location and the size of the vessels
5. The content of the extractives.
6. The rate of growth (Williams 16-3).

The majority of the wood cells which are delineated as being fibers in hardwoods and tracheid in wood species which are softwoods are aligned in parallel to the branch of the stem. The softwood species of tree is supported by the tracheid. The tracheid also performs the function of conducting nutrients and water throughout the tree. The hardwood species of tree is supported by the fibers, the hardwood species possess particular fibers which are applied for the conduction of nutrients and water. Pipes are formed by the vessel cells, in the softwood species of tree the tubes are composed of axially aligned tracheid (Williams 16- 3).

The pits enable the movement of the fluids from one tracheid to another. The ray cells are responsible for the movement of liquids from the center of the tree species to the bark. In the Douglas- fir, larch, pine and spruce tree species, there are resin canal systems which possess large apertures in the trees.Ray cells and axial cells are formed in the section of the tree which is called the cambrium. The cambrium is composed of a layer of cells which is beneath the bark (Williams 16- 3).

In the beginning of the trees’ seasonal development, the tree species which develop in the temperate climates possess cells which are composed of large open centers and slender cellular walls. This is the aspect of the springwood species of tree. As the growing phase progresses, the cellular walls thicken as the summerwood is formed.  The blending of the latewood and early wood tree tissues provide the annular rings which are applied for measuring growth in the tree species.The characteristics of the annular growth rings influences the facility with which the wood may be treated and the duration of the wood treatments. These aspectsaffect the service life of the wood (Williams 16- 3).

In order to explain the treatment characteristics of the wood species, the diverse wood species can be separated into three classifications. These classifications are the following:

1. Wood species which are easily treated. These wood species include the hardwoods which possess diffuse pores and the softwoods which have a gradual transition porous aspect.
2. Wood species which are treated with moderate ease. This includes the hardwood species whichare porous and the softwood species which possess thin latewood bands.
3. The wood species which are not treated with ease. This includes the hardwood species which are porous and possess rings and the softwood species which are of an abrupt transition characteristic (Williams 16- 3).

The most significant aspect of the wood anatomy is the appearance of the wood. The dimensional changes which are induced by moisture modification augment as a function of the specific gravity of the wood. . These modifications are more pronounced in the latewood than the early wood tree species. The distinct dimensional modifications for the wood species which are ring porous in comparison to the wood species which are abrupt transition occur at the early wood- latewood threshold. This aspect is significant due to the influences of the wood treatments which are applied (Williams 16- 3).

The tree species which have broad bands of early wood and latewood rings deter the capacity of the wood in absorbing the treatments which are applied. The capacity of the wood for receiving treatment is an importantaspect of the service life of the wood.

Water can exist in three distinct phases in accordance with the pressure and the thermal energy conditions. The first condition is gaseous. The second condition is steam. The third condition is ice. The fourth phase of water can existed as contained water. Moisture is not one of the phases of water. Moisture is a definition which is applied in order to apply uncertainty with regards to the phase of water (Williams 16- 4).

The moisture content of the wood may be referenced by the presence of the three distinct phases (gas, liquid and ice) in the wood species. A board which is composed of a wood species which possess 50% water content will manifest itself as liquid or ice within the cellular tissues of the wood. Water can also exist as contained water which is delineated as water which is confined between the cellular tissues of the wood.The quantity of water which is absorbed by the wood is reliant on the relativehumidity of the environment.  In the circumstance of the wood being stored in an environment which possesses 0% relative humidity, the effect of the environment on the wood will cause the wood cells to lose water by evaporation (Williams 16- 4).

In the circumstance of the wood being stored in an environment which possesses 100% humidity, the cells of the wood will absorb water from the environment.  In the wood being stored at a relative humidity which is found between the extremely dry and extremely humid environment, the wood will attain a stable 30% moisture composition. The moisture content of the wood is administrated by the relative humidity. When the relative humidity is in equilibrium with the external environment, the wood acquires a moisture content which is determined to be at equilibrium. The moisture content of the wood species varies as the temperature and the season change (Williams 16- 4).

The wood treatments are unable to change the equilibrium moisture content of the wood species. The treatments can only deter the indexes at which the evaporation and the absorption of water occur in the tissues of the treespecies.The wood which is influenced by the warming aspect of solar rays undergoes a relative humidity which is virtually below the environmental relative humidity. The surface of the wood species experiences an evaporation effect which occurs at a more elevated rate than the interior of the wood.The aspect of checking and cupping take place on the boards which are applied for decking, the upper surface of the board contains significantly less moisture than the lower parts of the board. The aspect of shrinkage which takes place at the top of the wooden plank cause the checking and the cupping of the wood tissues which are correlated to the desiccation of the wood.

The objective of this experiment is to review the distinct characteristics of the various wood species. This will be performed in order to ascertain which of the wood species can be optimally applied in the manufacture of a cutting board. The research question which will be reviewed is the correlation between the harness and ease of scratching of Oak, Beech, Ash, Sapele and Chestnut and to compare the qualities of these wood species with the qualities which are required for the cutting board which possesses high quality.

The research hypothesis which will be examined is which of the woods possess the greatest quality of impermeability and hardness. The first hypothesis is: The hardest and most impermeable wood species from the highest to the lowest order will be Oak, Beech, Sapele, Ash and Chestnut.The null hypothesis would be any conclusion which invalidates this order of the highest to the lowest with regards to impermeability.

The independent variable is the mass of the improvised tool which was applied in order to indent the wooden planks. The dependent variable is the depth of the indentation made by the improvised tool in the five distinct planks of wood. The controlled variables are:

1. The identical improvised tool being applied in all of the trials.
2. The identical wood being applied in each trial.
3. The surface which is clean and free from humidity, oils and dust.
4. Constant temperature.
5. Constant humidity.
6. Identical methodology for each of the wooden plank samples.
7. No motion of the wooden planks being empirically tested.
8. Identical height maintenance of the improvised too trials from a height of thirty one centimeters.

Materials

The materials which are used in this experiment are the following:

1. This is an improvised tool which was made. The picture is demonstrated above.
2. Additional weights which weigh 100g, 300 g and one kg each
3. Hinge which was attached to the tool in the photograph.
5. Five different wooden planks with measurement of 8.5 cm. in height, 4.5 cm in width and 1.5 cm in thickness. The five different categories of wood which will be reviewed are Oak, Beech, Sapele, Ash and Chestnut.
6. Experimental Design.
7. System for the Collection of Data

The initial experiment involves the investigation of the hardness aspect of the fivedistinct categories of timber. The meaning of hardness is the ability of a material to resist scratched or penetration. There are three types of hardness: rebound hardness, indentation hardness and scratch hardness. The aspect of indentation hardness will be selected in this experiment.

Procedure

1. Spaces were identified on each of the planks of wood for the distinct trials.
2. Subsequent to the classification of the space on the wood, a mark was placed on each of the five different categories of wood.
3. The improvised tool was released and allowed to impact the fixed planks of wood.
4. The dent which was made by the improvised tool was assessed with a digital Vernier caliper. There was a percentage of errorwhich is associated with the digital Vernier caliper which is insignificant.
5. Afterward the mass of the improvised tool had been increased by 100 g by adding a 100 g weight to the improvised tool.
6. Another impact position was marked on each of the wooden planks.
7. The improvised tool had been dropped for a second time onto the positions which had been marked.
8. The depth of the dent was measured with the digital Vernier caliper.
9. This process was conducted a total of three times with weights of  100g, 300g and one kg which were applied to the improvised tool.Steps 1 – 8 were repeated for a total of five times.

After the five different trials for each of the wooden planks (Oak, Beech, Sapele, Ash and Chestnut) the information was entered on a table.

Raw Data

In statistical analysis, the application of a linear regression graph is applied in order to demonstrate a relationship between the dependent variable y and the independent variable x. In this case, the dependent variable is located on the x axis in each one of the graphs. The independent y variable is located on the y axis of reach of the graphs. The graphs are used to demonstrate an equation which demonstrates the mathematical relationship between each of the variables. The linear regression line is directed toward the probability distribution which is conditional of the relationship between the dependent variable and the independent variable.  Linear regression can be used to predict the behavior of a particular set of data (NCSU 1).

The linear regression relationship indicates from the graph which was derived from the raw data that the hardest wood is Oak. The Oak is harder than the Beech. The beech is harder than the Sapele. The Sapele is harder than the Ash. The Ash is harder than the Chestnut. The application of the Pearson correlation coefficient was 0.6417385 for the Oak wood species, 0.0.8585997 for the Beech species, 0.84255436 for the Sapele species, 0.871133654 for the Ash wood species and 0.839273406. The strongest correlation between the independent and dependent variable had been demonstrated for the Chestnut wood species. Consequently, hypothesis 1 is accepted and the null hypothesis is rejected.

Experiment Two- Stiffness Testing

The content of moisture which is possessed by the wood has an influence on its stiffness. In the circumstance of the water concentration of the wood being in excess of the fibrous saturation limits, the mass of the wood is altered and its aspect of strength remains unchanged. In the circumstance of the wood being treated in such a manner where the water concentration which is presented decrease, the mechanical aspects in addition to the strength of the wood would be modified.  This relationship infers m that it is only the decrease of hygroscopic water which is the primary attribute in the increase in the wood strength. This process is acknowledged as seasoning (Williams 16-3; Xavier 573).

The objective of this experiment is to determine which of the five wooden plank samples which are being used is the most suitable for building a cutting board. The quality of stiffness of the distinct samples of wood species will be the goal of this experiment.

The research hypothesis which will be reviewed in regards to the aspects of the stiffness of the wood predicts the most impermeable woods to the least impermeable to the most permeable. The order of the least permeable to the most permeable wood be 1> 2> 3> 4> 5.The null hypothesis would invalidate the order of the least permeable to the most permeable wood.

Materials

1. Five wooden planks which represented each of the different wood species (Oak, Beech, Sapele, Ash and Chestnut). The dimensions of the wooden planks were 1.5 cm deep, 5.0 cm wide and 75.0 cm long.
2. Holes in the planks with a diameter of 3.2 cm.
3. The initial weight was measured at 0.5 kg. The subsequent weights were 1.5, 2.5, 3.5 and 4.5 kg.
4. String which suspended the weights from the hole which had been made in each plank. The weight of the string was negligible.
5. A gnomon was applied in order to measure the distance which had been moved by the wooden planks during the addition of each weight. The gnomon was placed on the table. The gnomon has an error of ±0.1 cm.

Procedure

1. Holes were bored at the extremes of all of the wooden planks.
2. The planks had been suspended by clamps which were secured to the experimental table.
3. The mass of 0.5 kg was suspended from the string which had been attached to the hole which was bored on the extreme end of the wooden planks.
4. The bending aspect of the planks had been measured with each incremental weight.
5. During each of the trails, one kg was added to the weights.
6. After the increase in weight the bending aspect of the planks was measured in cm.
7. The steps 1- 6 were continued for a total of eight times.
8. The data was entered on a table for evaluation (Xavier 575).

The independent variable in theexperiment was the mass of the weight which was suspended by the string which was attached to the holes at the extreme end of the wooden planks. The dependent variable was the distance where the wooden planks showed movement while they had been secured to the experimental tables by the clamps. The controlled variables were the following:

1. The identical mass being applied in each of the trials.
2. The identical wood being applied in each trial.
3. The surfaces which were clean and free from humidity, oils and dust.
4. Constant temperature.
5. Constant humidity.
6. Identical methodology for each of the wooden plank samples.
7. No motion of the wooden planks being empirically tested.
8. Identical length of string in each of the trials. The weights had been suspended on a string which measured 31 cm from the top of the wooden plank to the bottom of the first weight in each of the trials by a distance of thirty one centimeters.
9. The identical gnomon was applied in each of the trials.

Raw Data

Discussion

In the experiments which have been conducted, there are a number of ways in which the aspect of errorcould be improved. In the first experiment, the design of the hinge could have been improved. The lack of freedom of movement in the hinge may have affected the results which had been obtained in the experiment. The altitude of the improvised tool was maintained constant during each trial. As there was no precise method of assessing the height of the improvised tool prior to each of the trails, this aspect also provided room for error. The tip of the improvised tool which made the dent in the wood was worn. This aspect could have affected the outcome of the experiment and could have been improved.

In the second experiment, the aspect of the holes which were drilled could have affected the experiment. The initial manner of perfecting the experiment would have implied drilling the hole more precisely in order to accommodate the string with less room for movement. This would imply less of a pendulum movement in the weights which had been applied to the extremes of the wooden planks in order to induce bending. The gnomon which was used possessed an uncertainty of ± 0.1 cm. This uncertainty could have been the result of error in the experiment. In future experiments a gnomon which possess an uncertainty of ± 0.01 cm could be applied. The wood could have been stored in an environment which had been extremely dry of an environment which had been extremely humid. These aspects would have affected the outcome of the experiment. There are a number of items which could have been improved in order to diminish the error in the experiment.

Conclusion

The objective of the coursework was to ascertain which species of wood are optimal for the manufacture of a high quality cutting table. In the initial section of the experiment, the qualities which were required for the stiffness and the hardness of the wood were established. Consequently, the two experiments were planned in order to address the research question. The research question had been investigating the qualities of Oak, Beech, Sapele, Ash and Chestnut with regards to a comparison of the qualities of hardness and stiffness which were need for the construction of a high quality cutting table.

The results of the two experiments were the following:

Hardness_Oak > Hardness_Beech> Hardness_Sapele > Hardness_Ash > Hardness_Chestnut

Stiffness_Oak> Stiffness_Beech> Stiffness_Sapele> Stiffness_Ash> Stiffness_Chestnut

The project which was needed for a high quality cutting table has the requisite of hardness and stiffness. The most rational selection for manufacturing material would be Sapele. The outcome of the experiment one confirms the hypothesis of oak being the hardest wood species. The outcome of the second experiment confirms the hypothesis of Chestnut being the most flexible wood species. . The middle position of Sapele possesses the desired qualities of hardness and stiffness. These are qualities which are required for the manufacture of a high quality cutting table.

The values which have been demonstrated for the stiffness quality of the wood species which have been evaluated in this laboratory report have demonstrated that hypothesis 2 is valid. The null hypothesis is rejected. The Pearson’s correlation coefficient demonstrates that there is a weak correlation between the independent and dependent variables of the Oak, Beech, Sapele and Ash wood samples. There is a strong correlation which is demonstrated between the independent variable and the dependent variable for the Chestnut sample. Consequently, hypothesis two demonstrates that the most suitable wood for constructing the high quality cutting table would be Sapele due to itsmutual qualities of hardness and stiffness.

Works Cited

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“Fig 3c- anf05.”Web. 11 March 2014 http://www.scielo.cl/fbpe/img/maderas/v10n1/f3C_anf05.jpg

Legner, E.F. “Forest products & wood and cork.” University of California, Riverside, 2014. Web 12 February 2014http://www.faculty.ucr.edu/~legnere/botany/forsprod.htm

NCSU.”Lab write resources graphing with Excel.” NC State University, 2004. Web 12 February 2014 http://www.ncsu.edu/labwrite/res/gt/gt-reg-h-home.htm

“Research areas.” Web. 11 March 2014 http://cnr.ncsu.edu/fer/cafs/images/31-bendingstiffness.jpg

Williams, R. Sam. “Chapter 16: Finishing the wood.” Wood Handbook: Wood as an engineering material Volumes 72- 187. By Forest Products Laboratory. 1987. Web. 12- February 2014http://www.fpl.fed.us/documents/fplgtr/plgtr190/chapter_16.pdf

Xavier, José, Stéphanie Pierron, Fabrice José and Morais José. “Novel experimental a approach for the longitudinal radial stiffness characterization of clear wood by a s  single test.”Holzforschung 61.5(2007): 573- 581.