Tanalising Process

Tanalising is an environmentally friendly preservation process for timber applied during the seasoning process. It works by impregnating the wood with preservatives such as TANALITH E.

Tanalising wood means that the wood will waterproof the wood, but you still require the wood to be fungi free. So TANALITH E has some preservatives including a unique copper and organic biocide. These are used alternatively to arsenic which is more commonly used in CCA treated woods (Chromated Copper Arsenate)

Tanalised wood does not need any finishes such as varnishes but will tarnish over time to a grey colour due to the weather, sun and moisture. Being tanalised the timber has a distintive green tink to it but also becomes resistant to wood decay and animals.




1. The tanalising process involves placing the timber within a treatment cylinder and creating a vacuum within the timber cells

2. The cylinder is then flooded undeer vacuum with the preservative treaments

3. Hydraulic pressure is then used to force the preservative deep into the timber cells

4. After a dertermained period of pressure (depending on the type of timber and its use), the treatment solution is then pumped back out of the cylinder into a storage tank and the a final vacuum extracts excess solution from the timber

5. Low pressure inside the timber draws in surface solution when vented to atmosphere and the treated timber is left for a period of time for fixation of presvertion to occur

Wooden Joints

Choosing the correct wooden joint for the job at hand is key to the sturdy, final product. The key feature of a wooden joint is to optimize the amount of surface area for the glue to adhere the pieces of wood together.

Dowel Joints- Often used for accuracy, dowel joints are useful and easy to drill adn make. the dowels are most oftenly made out of a hard wood called Ramin and come in a range of widths from  4 to 25mm. Typically pocessing grooved curfaces for glue to adhere.

 

 

Mortice and Tenon- Most oftenly found in furniture, mortice and tenon joints are used in furniture legs where two rails are joined to a leg at each corner. The ends are mitred where they meet inside the leg to create maximun strength in the glue bond.

Dovetail-
Through Dovetail- Often used in the back of drawer, the tapered shape of the finger like pieces prevent the drawer from falling part when an opposite force is applyed. they are not only used for their strength and resistance but also their decorative qualities
Lapped Dovetail- Lapped dovetail joints equally are as strong as the through dovetail joints but are not visable. this is because part of the wood laps over the dovetail. These are most commonly used in drawer fronts

Finger Joints- Also known as Combe Joints, finger joints are a simply fairly easy joint to manufacture as there are not any angles included like the dovetail joint. These joints are ideally suited to industrial situations where it is produced using machine tools.

Steam Bending

Steam bending is a woodworking process by which wood is reshaped with the use of heat and moisture. The heat and moisture makes the wood more pliable and therefore allows it to be moulded around a jig, former or mould.

The way heat and moisture makes wood pliable is throught the structure of the wood.
Woods are made up of many fibres looking very much like straws, these features allowed wood to transport water to the tops of the tree.

The problem with using moisture with wood is that too much moisture can cause the wood to swell and loose its rigidity. So the amount of moisture has to be controlled to ensure the wood does not defect during the moulding stage.

The second problem with steam bending is that not all wood can easily be shaped, this is because in hardwood the fiblres are much more compacted and threrfore harder to form. Also the thicker the piece of wood the harder it is to bend. If there is not enough moisture the wood will simply snap but too much would ruin the wood's structure and aesthetics

Engineered boards

Engineered Boards

 

Hardboard:

Hardwood is created by compressing wooden fibres into a thin sheet of board with the addition of glue or resin base.

 

Uses: Cabinets, Countertops, Furniture

Thicknesses: 3mm

 

Blockboard:

blockboard is made by sandwiching softwood blocks between two wooden sheets under intense presure and glue. the outer sheets of wood can be softwood, hardwood or egineered board

 

Uses: Doors, Tables, Shelves, Paneling and Partition Walls

Thicknesses: 13mm- 30mm

 

Plywood:

Plywood is made up by compressing thin layers of wood together with the addtion of glue. the pieces of wood are then compressed to form one thick board. Plywood is very strong because of the crossing of grain within it production

Uses: Furniture, Sheds, Blackboards, Billboards and Kitchen

Thicknesses: 6.5- 30mm (Maximum thickness is 50mm)

 

MDF- Medium Density Fibreboard:

 

Uses: Furniture, Laminate Flooring, Shelving, Decorative Moulding and Doors

Thicknesses: 3mm- 32mm

 

Chipboard:

 

Uses: Flooring, Countertops and Furniture

Thicknesses: 12mm, 18mm

Uses of Plastics

• Lego- Lego is made out of ABS (acrylonitrile butadiene styrene). The advantages of this is that...
• It is ideal for the injection moulding process as all pieces are going to be exactly the same
• Durability (pieces knocking together in the box). As well as children throwing and the pieces about
• Free of any toxins as it is used for childrens toys which could inflict health problems, although it is restricted to children above the age of 3 due to small hazardous parts.

• Plumbing Pipes and Guttering- Plastic piping is most commonly produced by PVC (PolyVinyl Chloride. This is because...
• It can be extruded easily during maufacture
• It can be easily shaped with the presence of a plasticizer
• It is cheap to produce therefore cost effective
• Waterproof allowing for suitable water drainage
• Low maintenance making it ideal for permenant fixtures



• Hard Hats- Hard Hats are made out of HDPE (High Density PolyEthylene. The benifits of this is that...
• HDPE can be used in injection moulding, cheap and efficient with no waste product
• HDPE is resistant to impact damage
• Resistant to sharp object.
• HDPE can spread the impact force over a larger surface area minimalising impact for

 

Plastic Moulding

Injection Moulding-



Extrusion Moulding-
This process is a continuous process used to produce solid and hollow products that  have a constant cross-section.

• Thermoplastic granules are fed from a hopper through a heated cycinder by a rotational screw
• the tapered shape of the screw compacts the plastic as it travels through the the heated cylinder towards the die
• the die determineds the shape of the cross section of the plastic when it is extruded through the die opening
• Extrusion rates vary from 9 to 60 metres p/minute. The thinker the cross section the longer it will take to extrude
• as the extrusion is complete the product passes through a cooling trough which contains cold water
• after cooling the product is cut to specification/ requirements automatically

Vacuum Moulding-
This process is used to manufacture a wide range of thermoplastic products. these products vary in size from food trays to interior vehicle panels

• A desired mould is placed upon a platen (support plate)
• the platen and mould are lowered, Rigid thermoplastic sheet material is then clamped onto an air tight gasket and heated from above
• After the sheet has softened, air is blown uder the sheet to raise it into a bubble shape before the platen is raised bringing the mould into contact with the plastic
• Any trapped air is then removed using a vaccum pump which ensures that the plastic has taken complete shape of the mould
• Once the plastic sheet has cooled to below its freezing point, the air flow is reversed to remove the plastic from the mould
• Once completed the waste material is then cut from the plastic sheets and recycled

Rotational Moulding-
This process is mainly used to manufacture hollow objects such as footballs, road cones and storage tanks

• Moulds are mounted and rotated contnuously by three rotational arms
• Firstly, The moulds are filled with thermoplastic powder, which is measured only to coat the outer edges before closing the mould for the next stage
• whilst being rotated (both horizontal and vertically) the mould is subjected to 230°C - 400°C
• as tyhe mould rotates it's inner surfaces are coated with the powder which turns to plastic with the extreme heat applied. Producing an even thickness of plastic inside the mould
• Whilst still rotating the mould is then moved into a cooling area where it is cooled by air or water jets
• Once cooler enough to retain it's own shape, the products are removed from the moulds and in some cases to prevent distrosion to the shape during final cooling. A jig can be applied, this is often with flat surfaces (eg storage containers)

Polymers

Polymers are long chains made up of induvidual monomers. The raw material used to create polymers is found in crude oil therefore making them a finite resourse.

polymers are widely used from wiring insulator to window frames. This is because polymers have many different properties including

• Good Insulator to Electricity and Heat
• Good Strength to Weight ratio
• Good resistance to atmospheric and chemical erosion
• Low melting points
• Lightweight

There are two types of polymers, Thermosetting and Thermo

Theremosetting polymers

Thermosetting polymers cannot be remoulded once cooled, this is because of the molecular structure of them. This does make them ideal for saucepan handles and kettles ect.
Some examples of thermosetting plastics are.

• Epoxy Resin
• Melamini Formaldehyde
• Polyester Resin
• Urea Formaldehyde

Thermo- polymers

Thermo polymers can be remoulded repeatedly as the bonds in the molecular structure are weak, therfore applying heat to the material makes it maluable

ABS- Acrylonite Butadiene Styrene
CA- Cellulose Acetate
Nylon- Polyamide
PMMA- Poly Methyl Meth Acrylate (aka Acrylic)
PP- Poly Propylene
HIPS- High Impact PolyStyrene
PS- Poly Styrene
LDPE- Low Density PolyEthylene
HDPE- High Density PolyEthylene
uPVC- PolyVinyl Chloride
PVC- (un plasticised flexiable) PolyVinyl Chloride
PET- PolyEthylene Terephthulate
PC- Poly Carbonate

Plastic Additives

Fillers-

Flame Retardants-

Antistatic-

Plasticizer-

Stabilizer-

Mini Chair Project

I Should Never Have Purchased!

Late January I had a fair amount of my Christmas money remaining leaving me perplexed on what to spend my money on. I wanted to find something that was not too expensive, but at the same time something that would not be forsaken and left at the back of the cupboard after a week of use.

10 Inch Touchscreen Android Tablet

After searching the web I came across an android tablet. the tablet was a 10 Inch Touchscreen Epad tablet. On initial glance the aesthetics of the product looked familiar to the Apple tablet the Ipad. The functionality of the product also seemed pleasing as it was described as having a crisp touchscreen display, built in mic and quality sound for a tablet of its type. All of these features draw me away from the fact that I was buying a cheap copy of the Ipad running off of a poor quality Android Operating System.

When I received the product the aesthetics were simply of the quality I paid for...cheap. And as of the "crisp" touchscreen the device retained...well it was extremely resistive and had lost its crisp touch it was once described of having. Upon the issues with the display, the ergonomics of the device were not great either. Not the physical ergonomics but instead the practicality and how easy it was to operate. For example the battery life did not exactly allow you to use it often as it did not last any longer than 2hrs at most.

In my opinion the device was useless and within a month of getting it, it discovered the dark fate of the cupboard. Ultimately by trying to save money on a tablet I instead wasted money on a tablet that's functionality was of suitability for a child's toy.