Man-Made Boards, Veneers and Wood Finishes

Man-Made Boards

There are many different types of Man-Made boards, made up from things varying from chippings to fibres. The most commonly used size of board available to buy in a shop is 2440mm by 1220 mm then the thickness is decided by the Manufacturer going up in steps of 3mm starting at 3mm and going up to a large but theasable amount.

All the boards below are Man-Made.

Plywood is made up from alot of different layers of wood with all their drains facing in different directions to counteract eachother therefor making the wood strong in all dfirectiong rather than if the grains were all facing the same way where the wood would be strong along the grain but weak across it. Plywood gets its strength from the direction of its grains.

Marine Plywood is named so because it is more resilient against wateras it has a layer of plastic based paint coating it which seals off all the fibres and stops water getting into the wood.

Mdf stands for Medium Density Fibreboard, it is made up from fibres from wood which are all added together and pulped down like paper is and then an extremely strong adhesive is added to it and then a certain amount of pressure is applied. Hdf stands for High Density Fibreboard which is the same process as from MDF except more pressure is applied to the board making it denser.

Both MDf and HDF have adhesive in them, the adhesive which is harder than the wood itself gives the wood blunting properties so if MDF was to be used in a large scale production there would be a cost implication as the saws will often get blunt or broke.

Hardboard is alot cheaper than Plywood as the strength of Plywood isn't needed in Hardboard therefore it doesnt need as many layers or the layers to be arranged in the same fashion which means that Hardwood is one of the cheapest types of Man-Made Boards available. Hardboard is weak,brittle and is very absorbant to water and because of that is often used to fill in gaps. It is most commonly used as the back of furniture. If Hardboard does get wet the fibres within it will suck up the liquid and then make the wood rotten and useless.

Chipboard is most commonly used for kitchen worktops and units and etc. Chipboard is made of big wood chippings and is made using a similar process as MDF or HDF by pulping the chippings together then adding adhesive and pressure. Chipboard usually has a Veneer or Laminate on top to make the material look more attractive by hiding the chipboard underneath.

Blockboard is made from a different process to ensure it has good aesthetical properties. Long strips of cheap and otherwise useless wood are glued together between two Veneers who give the material its aesthetical properties. The Veneers are what cost the most money in making Blockboard.

Aeroply is used in the structure of plane wings. The material is made in a way which gives it the properties making it capable of bending around objects or frames.

Maplex is like a higher grade of MDF board used for furniture. It is new and easier to machine. It is high density and made up from pure wood fibres, Maplex is a new material and looks and acts alot like sheet metal.

Veneers

Veneers are basically a slice of wood ranging from 1.5mm to 4 mm thick. They are usually used by being glued to less attractive Man-Made boards such as chipboard and they used in more affordable furniture or kitchen.

There are two main types of Veneering ; Slice Veneering and Rotary Veneering.

Slice Veneering is involving a piece of wood that is is usually raised and lowered against a blade, thus then slices of the log are made. this makes the veneer have some marks of growth rings on it. This gives a decent decorative pattern which can be used for a variety of uses and is cheaper to make therefore buy compared to Rotary Veneering.

Rotary Veneering uses a rotary lathe in which the wood is turned against an extremely sharp blade and then peeled off like the skin of an orange. Rotary-cut veneers are mainly used for plywood because the appearance isn't great or nice like it is if slice veneered.

Wood Finishes

All Wood is finished in some way or another.

Polyurethane Varnish is a plastic based varnish that can be bought in matt, satin or gloss finish and it keeps the water out of the wood as it is plastic based

wood stain = colours the wod

wood oils are rubbed into the wood and is usually used for furniture.

preservatives can make the woods life 4 or 5 times longer and is generally used in outdoor furniture

Steam Bending And Laminates

Steam Bending

Steam Bending uses hot steam to get absorbed into the woods that in turn makes the wood more flexible. Once the wood has been shaped into the shape desired the shaped wood is then seasoned to remove the moisture content into the vorrect amount depending of the environment of where the wood will be used.
The process is used in both small scale and large scale production and the products can make anything from stairs to chairs.
It takes about one hour to steam a piece of wood per 25mm thickness of the wood.
So;
50 mm thick = 2 hours steaming
75 mm thick = 3 hours steaming
and so on.

Laminated Wood

Laminates are made up from a variety of layers all bonded together using an adhesive which is in fact stronger than the wood itself which makes the finished Laminate extremely strong and hard.

The layers of wood have all their grains going in different directions alot like in Plywood which makes the woods strong in all direction which it wouldn't be if all the grains were facing the same way. Laminates are sometimes used as decorative features such as flooring. One of the most commonly found uses for Laminates is Laminate flooring.

notes write up from - friday 4th september 09 and 2nd october 09

1) We learnt about steels and woods and the many types of both.
There are alot of different types of steels and in a-level tests simply saying "steel" rather than a particular type of steel isn't good enough.
The most commonly used steel is mild steel as it is easier to use and weld and etc.
Timber is a natural sustainable resource.
2) Soft woods are trees like Firs and Pines, more commonly known as "evergreens" as they do not shed their pines. they grow faster than hardwoods and because of that they are cheaper.
3) hard woods are woods such as Mahogany and Oak which take longer to grow and the hardwood trees have leaves. they cost more as more of the woods are rarer like mahogany and ebony trees.

Timber is fiberous which means it is pretty much made up of fibres, 55% of the tree is made up of Cellulose, 28% resin. therefore there is alot of moisture in timber.

Trees that have been cut down usually go through this cycle:
1) Harvest the tree
2) Chop up into boards ( converting )
3) Seasoning it (dry it)
4) Board preperation

I also found out that Quarter sawn wood is stronger than plain sawn wood, it leaves more wastage But it is alot stronger and bows alot less when dried out as the annual rings are shorter which means when it bows along the annual rings it bows alot less as the rings are shorter. Unlike when the wood is plain sawn where the annual rings are usually quite long which get shrunk along thus creating bowing.

Things to think about when buying wood:
1) Physical strength - Timber alot stronger along the grain rather than across it.
2) Asthetic properties - Knotts in wood , colour , complex or simple grain structure.
3) Moisture content - Shrinkage/timber movement , where the wood will be used ie ; outside, central heated house.
4) Protection - Dry/Wet rot , Insects.
5) Cost - Harwoods more expensive, Softwoods Cheaper, Rare woods usually very expensive.
6) Sustainability/Environmental issues- Using timber.
7) Size- Size of board available, may have to glue different boards together if wood size wanted not available.

Some examples of Softwoods are : Scots Pine, Douglas Fir , Paranah Pine, Larch and Spruce

Some examples of Hardwoods are: Ash, Oak , Beech , Mahogany , Teak , Walnut and Mahogany

F.S.C stands for the Forestry Stewardship Council

things i should never have bought!

I Should Never Have Bought!

A long while back I bought myself a Sony Ericsson walkman phone, the product on the whole I believed was good, it was a good looking phone and it was stylish aswell. All was well until a few weeks after my purchase when I noticed a fatal flaw in the design, the socket in which the phone charger end was inserted and also the headphone adapter was an absolutely atrocious design, the charger was held in place when charging by two small plastic bits, and the phone was charged by a few measly tiny metal prongs.
I found out from personal use that even with very little wear-n-tear eventually the plastic of the charger and headphone jack softens from being put in and pulled out all the time and the metal prongs wear out aswell so even if you eventually connect the charger most of the time it doesn’t work! Then if it doesn’t work like that you have to struggle to get into a really awkward position so that the prongs will connect and charge your phone!
I also know that I am not the only one suffering at the hands of the flawed Sony Ericsson phones lots of people I know always complain about it, things like the headphone jacks always break so they need to buy new ones.

Is it an honest flaw in the design or another way of getting people to buy more of their completely rubbish chargers and headphones?