Selasa, 04 Juni 2013

SKATEBOARD

A skateboard is a type of sports equipment used primarily for the activity of skateboarding. It usually consists of a specially designed maplewood board combined with a polyurethane coating used for making smoother slides and stronger durability. A skateboard is propelled by pushing with one foot while the other remains on the board, or by pumping one's legs in structures such as a pool or half pipe. A skateboard can also be used by simply standing on the deck while on a downward slope and allowing gravity to propel the board and rider. If the rider positions their right foot forward, he/she is said to ride "goofy"; if the rider positions their left foot forward, he/she is said to ride "regular". If the rider is normally regular but chooses to ride goofy, he/she is said to be riding in "switch", and vice versa. A skater is typically more comfortable pushing with their back foot; choosing to push with the front foot is commonly referred to as riding "mongo." Recently, electric skateboards have also appeared. These no longer require the propelling of the skateboard by means of the feet; rather an electric motor propels the board, fed by an electric battery. There is no governing body that declares any regulations on what constitutes a skateboard or the parts from which it is assembled. Historically, the skateboard has conformed both to contemporary trends and to the ever evolving array of stunts performed by riders/users, who require a certain functionality from the board. Of course, the board shape depends largely upon its desired function. Longboards are a type of skateboard with a longer wheelbase and larger, softer wheels. Skateboards have three axes. The tail axis (running from nose to tail), the central axis (running straight down through the center of the board), and the short axis (running from the width of the board, perpendicular to the tail axis). The two main types of skateboards are the longboard and the shortboard. The shape of the board is also important: the skateboard must be concave to perform difficult tricks.[1] Parts Descriptions of the following skateboard parts are the ones most prevalent in popular, modern forms of skateboarding. Many parts exist with exotic or alternative constructions. Most decks are constructed with a six to seven-plywood, the deck, trucks, wheels, bearings, hardware, bushings and griptape. Older decks also included plastic parts such as side, tail, and nose guards. Deck The side of a skateboard Modern decks vary in size, but most are 7 to 10.5 inches (17.78 to 26.67 centimeters) wide. Wider decks can be used for greater stability when transition or ramp skating. Skateboard decks are usually between 28 and 33 inches (71.12 and 83.82 centimetres) long. The underside of the deck can be printed with a design by the manufacturer, blank, or decorated by any other means. The longboard, a common variant of the skateboard, has a longer deck. One of the first deck companies was called "Drapped" taken from Jonny's second name. "Old school" boards (those made in the 1970s–80s or modern boards that mimic their shape) are generally wider and often have only one kicktail. Variants of the 1970s often have little or no concavity, whereas 1980s models have deeper concavities and steeper kicktails.[citation needed] Grip tape, when applied to the top surface of a skateboard, gives a skater's feet grip on the deck. It is most often black but can come in a variety of colors including clear, allowing the top of the deck to be decorated. It has an adhesive back and a sandpaper-like top. Trucks An Independent brand skateboard truck Attached to the deck are two metal (usually aluminum alloy) trucks, which connect to the wheels and deck. The trucks are further composed of two parts. The top part of the truck is screwed to the deck and is called the baseplate, and beneath it is the hanger. The axle runs through the hanger. Between the baseplate and the hanger are bushings, also rubbers or grommets, that provide the cushion mechanism for turning the skateboard. The bushings cushion the truck when it turns. The stiffer the bushings, the more resistant the skateboard is to turning. The softer the bushings, the easier it is to turn. A bolt called a kingpin holds these parts together and fits inside the bushings. Thus by tightening or loosening the kingpin nut, the trucks can be adjusted loosely for better turning and tighter for more stability. Standard Kingpin nut size is 3/8" - 24tpi. Skateboard trucks are manufactured in a number of different axle widths. In general an axle width should be chosen that is close to the width of the deck it will be used with.[2] For example, a 7.75" wide deck will usually be fitted with trucks that have axles between 7.5" wide and 8.0" wide. (Standard truck axel nut size is 5/16"-24tpi UNF, and the thinner "jam" style with an optional nylon lock.) Trucks that are too wide can make doing tricks difficult and can cause the wheels to get in the way when the skateboard is being ridden. Trucks that are too small can be hard to maintain stability and can cause wheel bite to occur when turning. Longboard specific trucks are a more recent development. A longboard truck has the king pin laid at a more obtuse angle (usually between 38 and 50 degrees[3]) to the deck, this gives a greater degree of turning for the same tilt of the deck. This allows riders to go much faster while still maintaining stability and control. Giant strides have been made in the truck industry over the years. In late 2007, Gullwing Truck Company manufactured a truck named "Sidewinder" that can pivot on two different angles, thus greatly decreasing the turning radius of the board, resulting in a greater feel between the rider and the sidewalk. Wheels The wheels of a skateboard, usually made of polyurethane, come in many different sizes and shapes to suit different types of skating. Larger sizes like 54–85 mm roll faster, and move more easily over cracks in pavement. Smaller sizes like 48–54 mm keep the board closer to the ground, require less force to accelerate and produce a lower center of gravity, but also make for a slower top speed. Wheels also are available in a variety of hardnesses usually measured on the Shore durometer "A" scale. Wheels range from the very soft (about Shore A 75) to the very hard (about Shore A 101). As the A scale stops at 100, any wheels labeled 101A or higher are harder, but do not use the appropriate durometer scale. Some wheel manufacturers now use the "B" or "D" scales, which have a larger and more accurate range of hardness. Modern street skaters prefer smaller wheels (usually 51–54 mm), as small wheels with lighter trucks can make tricks like kickflips and other flip tricks easier by keeping the center of gravity of the skateboard closer to the deck, thus making the deck easier to spin. Street wheels are softer. Vertical ramp or "vert" skating requires larger wheels (usually 55–65 mm), as it involves higher speeds. Vert wheels are also usually harder, allowing them to maintain high speed on ramps without sliding. Slalom skating requires even larger wheels (60–75 mm) to sustain the highest speeds possible. They also need to be soft and have better grip to make the tight and frequent turns in slalom racing. Even larger wheels are used in longboarding and downhill skateboarding. Sizes range from 65 mm to 100 mm. These extreme sizes of wheels almost always have cores of hard plastic that can be made thinner and lighter than a solid polyurethane wheel. They are often used by skateboard videographers as well, as the large soft wheels allow for smooth and easy movement over any terrain. An Animation of the working principle for a ball bearing. N.B. The diagram shows an 8-balled-bearing whereas a skateboard bearing is typically 7-balled Grip tape Grip tape is a sheet paper or fabric with adhesive on one side and a surface similar to fine sand paper on the other. Grip tape is applied to the top surface of a board to allow the rider's feet to grip the surface and help the skater stay on the board while doing tricks. Grip tape is usually black, but is also available in many different colors such as pink, yellow, checkered, camo, and even clear. Often, they have designs die-cut to show the color of the board, or to display the board's company logo. Bearings Each skateboard wheel is mounted on its axle via two bearings. With few exceptions, the bearings are the industrial standard "608" size, with a bore of 8 mm, an outer diameter of 22 mm, and a width of 7 mm. These are usually made of steel, though silicon nitride, a high-tech ceramic, is sometimes used. Many skateboard bearings are graded according to the ABEC scale. The scale starts with ABEC1 as the lowest, 3, 5, 7, 9. It is a common misconception that the higher ABECs are better for skateboarding, as the ABEC rating only measures tolerances, which do not necessarily apply to skateboards. Bearing performance is determined on how well maintained the bearings are. Maintenance on bearings include periodically cleaning and lubricating them[1]. Bearings that are kept unmaintained have their performance greatly lowered and will soon need to be replaced. Bearing cleaning kits are commonly available on the market. The ABEC rating does not determine how fast or how durable a bearing used for skateboarding will be.[4] In particular, the ABEC rating says nothing about how well a bearing handles axial (side-to-side) loads, which are severe in most skateboard applications. Many companies do not show the ABEC rating, such as Bones Bearings, which makes bearings specifically for skateboarding, often marketed as "Skate Rated". Each bearing usually contains 7 steel or ceramic ball bearings, although other configurations are used as well. Hardware Mounting hardware is a set of eight 10-32 UNC bolts, usually an Allen or Phillips head, and matching nylon locknuts. They are used to attach the trucks to the board. Some sets have one different colored bolt to show which side is the nose of the skateboard. Hardware is available in various lengths for mounting trucks with or without risers.

Cara Alami Mengatasi Rasa Kesemutan di Kaki dan Tangan

Cara Atasi Kesemutan di Tangan dan Kaki

 Hai shobat semua, Apa kabar? Mudah mudah2an saat ini shobat semua dalam keadaan sehat semua. Pada kesempatan kali ini Kak Imam akan share tentang Cara Alami Menyembuhkan Kesemutan di Kaki dan Tangan .
Berikut ini adalah cara mengatasi kesemutan caranya tidak terlalu sulit, cukup dengan memperbaiki aliran darah di bagian tubuh yang kesemutan. Boleh dengan cara memijat atau melepaskan bendungan yang jadi penghambat aliran darah. Atau, dengan memberikan obat-obatan untuk mengembalikan fungsi saraf sehingga kesemutan hilang. Misalnya, kalau kita terlalu lama duduk bersila, biasanya ketika bangun akan mengalami kesemutan, maka secara perlahan digerak-gerakkan saja bagian yang kesemutan tadi akan hilang atau biasanya dengan cara menghentakkan kaki ke lantai.

Apabila kita duduk dalam jangka waktu yang cukup lama dengan posisi yang tetap atau sama , kemudian di saat kita berdiri biasanya terjadi kesemutan pada kaki kita. Hal ini sering kita alami. Nah untuk mengatasi rasa kesemutan pada kaki kita saya punya cara yang benar-benar mudah seperti berikut ini :



Ikatkan gelang karet pada ibu jari kaki yang kesemutan atau keseluruhan kaki kita ikat. Usahakan ikatannya jangan kuat-kuat atau pun terlalu kendur , sedang-sedang saja. Kemudian diamkan beberapa saat. Jika udah begitu maka tak berapa lama lagi kesemutan dikaki kita biasanya akan hilang.

Tapi untuk kesemutan biasa yang disebabkan adanya gangguan pada fungsi saraf bisa diatasi dengan minum vit B1, B6 dan B12 karena Vitamin B1, B6, dan B12 disebut vitamin neurotropic, yaitu vitamin yang akan membantu perbaikan fungsi-fungsi syaraf dan berfungsi sebagai zat pengantar dalam metabolisme tubuh. Ketiga vitamin tersebut tidak dapat diproduksi tubuh, maka harus dipenuhi dari makanan. Proses metabolisme berlangsung setiap hari, sehingga tubuh kita membutuhkan vitamin neurotropic setiap hari.

Bila Anda terlalu sensitif sehingga gampang kesemutan, bisa dikarenakan pada dasarnya sensitif. Namun bisa juga hanya karena terlampau kurus, sehingga sarafnya bertonjolan. dapat pula dilakukan dengan cara berolah raga secara kontinyu, sambil tetap menjaga sikap tubuh yang baik, mempertahankan pola makan sehat, dan menghindari stres, jauhi alkohol juga.

Kalau gejala kesemutan itu makin lama makin berat, intensitasnya makin tinggi, bidang cakupannya makin luas dan frekuensinya makin sering, segeralah periksakan diri ke dokter, karena kemungkinan kesemutan ini merupakan gejala dari penyakit yang serius.

Nah sekarang udah tau kan cara mengatasi kesemutan,silahkan di coba semoga bisa bermanfaat untuk shobat semua