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Forehand Vs Backhand MIG Welding Techniques

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Forehand and backhand welding are the most basic of all welding techniques. They are simple, have their purpose and provide a specific type of weld when used properly. In this article you will learn why these techniques are used and most importantly why.

Forehand Technique

Forehand is a technique where the welder pushes the puddle and keeps the arc slightly ahead of the puddle. Forehand welding is done with the MIG gun pointed in the direction of travel. For example, if the welder will be welding from right to left, then the MIG gun will point toward the left at all times. The angle that the MIG gun is pointed toward the direction travel can vary. The angle of the MIG gun can be anywhere between 5 degrees to as much as 35 degrees toward the direction of travel. When traveling forehand the welder must focus on keeping the arc slightly ahead of the puddle.

Backhand Technique

The backhand technique is the exact opposite of the forehand welding technique. In the case of back hand welding the welder keeps the MIG gun pointed toward the weld while traveling away from it. For example if the welder is welding from left to right then the MIG gun will be pointed toward the left. The angle of the MIG gun can vary between 5 degrees to 35 degrees toward the weld.

Understand the Reasons for these Welding Techniques

These MIG welding techniques do serve a very important purpose. What they do is control the weld shape and the penetration pattern.

Forehand welding is the most commonly used technique for MIG welding. What the forehand method does is produce a shallow but wide penetrating weld that is flat in appearance. This is the type of weld and penetration is used for most weld joints where overheating is not an issue.

Backhand welding is the least used welding technique when it comes to MIG. This technique produces the deep and narrow type of penetration that is best suited for thinner metals. The advantage of backhand welding is that the arc is focused onto the filler metal and that means extra material to prevent burn through. When welding thinner metals you always run the risk of burning a hole through the weld joint. With the backhand method the extra filler metal at the arc helps prevent this and at the same time can keep warp age to a minimum.

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What is This New Backside Illumination on the New iPhone?

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Recently Apple announced the new iPhone and a number of the hardware changes were targeted at the camera. Thanks to the infamous lost iPhone fiasco we expected the 5 mega-pixel camera and flash, but Jobs announced the camera had backside illumination. That left us puzzled so we did a some research on camera chips.

What is backside illumination?

First stop giggling… OK… I’ll admit I think they could have found a better name. Some of the jokes I saw on Twitter seemed to be especially crude about this feature. Backside illumination is a trick of getting better digital photos by getting more of the available light to where it is measured.

First an overview on digital cameras

The key part of all digital cameras is a chip called the CCD (charge coupled device) which senses the light falling on its surface. The light affects the charge a grid of millions of tiny capacitors created on the silicon when the chip is made (making chips is called fabrication and involves a lot of etching and depositing of thin layers and different materials in precisely controlled ways). For simplicity just think about black and white CCD’s where the array of capacitors corresponds to the array of pixels which make up a digital image (color sometimes uses a lot more tricks). The chip has additional circuitry that measures the charge of all of the capacitors which is basically how the light levels of the image are read. To be able to read all of these capacitors there are minutely thin wires running over the top. They’re not actually wires but a thin layer of aluminum or copper that is effectively sprayed on to the chip and then carefully eaten away using acids to leave connecting traces, which are pretty much metal wires bonded to the chip.

Why backside illumination?

All those wires and other parts of the capacitors sit on top of a square silicon tile (called the die) with the capacitors at the bottom. The circuitry and wires don’t obstruct it too much as it works but it does block some light and scatter some in to surrounding capacitors which reduces the quality of image captured especially with limited lighting. Back to that square silicon tile. Silicon is the main ingredient of regular glass (aka silicon dioxide) but the stuff used in making chips is a super pure silicon crystal and transparent. With backside illumination the issues with traditional CCD’s of the capacitors being on the bottom is quite literally turned upside down and now you shine the image on what was the bottom of the silicon tile and let the light shine through the silicon to the capacitors. This way you avoid all the wires and get more light to the capacitors.

With this new camera chip Apple has shown some beautiful looking pictures but they key performance area will be low lighting. Capturing scenes like the last light of a fading sunset. The earlier iPhones (Original and 3G) had very basic fixed focus 2 mega-pixel cameras which struggled in low lighting. The 3GS brought auto focus and auto white balance that improved performance but still struggled with such scenes, often distorting colors. Now with the new camera chip the iPhone should take vastly improved photos, coupled with the in-built flash to handle low lighting indoors.

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WOW Golden Pearl Farming – Fast Way to Make Gold on WOW

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Using the Auction House for making gold on WOW is the fastest way to make it on WOW. But what do you do if you need some fast way to make gold on WOW to begin with?

Many players are trying to farm gold as a fast way to make it on WOW – but that is not the best way, it is not even a good way for making gold on WOW at most cases.

Farming is only good at high level and even then it is not the best way!

This is true especially because when you level up you can make more gold at less time – so you will want to start by leveling up as fast as possible before you start farming in the first place.

But there is an exception to that rule – WOW Golden Pearl Farming!

WOW Golden Pearl Farming is good as they can be sold for a lot of gold at the WOW Auction House most of the time.

There are times that Golden Pearl are sold for 4g-5g, but more often than none you can sell them on the WOW Auction House for a very high prices – that is 80g-100g and even up to 200g per pearl!

This means that if you can get 4-6 Golden Pearls an hour from farming you can make between 500g to 1000g per hour, and you can start farming for Golden Pearl from as low level as 40 while leveling in the same time, or go pearl farming as a fast way to make gold on WOW at a low level as 50.

The secret is not to farm for the pearls themselves but to farm for specific clams that drop them as well as buy them from the WOW Auction House itself.

You see there is a secret for farming those pearls, and you will be amazed how simple it is to get them.

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WoW Best Gold Farming Spots in Wotlk – Wrath of the Lich King

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There is a great need for any player who wishes to survive in the recent expansion to the World of Warcraft (WoW), the Wrath of the Lich King (WotLK). Just like in the real world, living in WoW has become more expensive as new garb and weapons are becoming pricier. Even relaxing at a pub in Dalaran could be worth some amount of gold. This has spurred the emergence of not a few WoW gold guide articles that aim to help the WotLK gamer in farming for gold in Northrend. Most of these articles would tell you where to go to farm WoW gold and the fastest way to make gold in WoW. Even the best WoW gold making guide contains almost the same tips and techniques that you’ll find in these WoW farming for gold articles.

Here are some WoW money making tips that are constantly referred to in these WoW farming guides:

1. Get the right gathering profession. Having the right profession will allow you to be able to build on the right skills to make gold. The best professions are those that are easy to level up and easy to earn gold in. Some of these professions include:

o Mining: Your ores can fetch you lots of gold. If you max your gathering skill level into grand master level, you will be able to mine most ores. You can go to the Burning Steppes and the Un’goro for Mithil and Thorium or the Netherstorm, Terokkar, and Nagrand for Adamantite ore.

o Herbalism: You can find a lot of herbs to sell for gold in the different zones of WoW. You can find some Mana Thistle in the Outlands or some Nightmare Vine drops when you go to Shadowmoon Valley. Other herbs that you can find are Fel Lotus, Ancient Lichen and the Netherbloom.

o Skinning: There is a huge amount of gold that can be made with selling rare leather like those made from cobra scales and wind scales. These can be found at the Shadowmoon Valley, nagrand, and the Blade’s Edge Mountains. You can even be crafty enough to make these into armors and other more useful items to make it worth more gold.

2. Max your crafting profession: Just like your gathering profession, you need to make sure that your crafting profession level is way up before you enter the WotLK. These professions include alchemy, jewelcrafting, and leatherworking. As you would note, these skills can be combined with your gathering professions to be able to increase the gold values of your gathered items.

3. Trade your goods: Watch the auction house. You can make more gold in finding out which ones are selling for less amounts of gold but with potential of selling for higher amounts of gold at a later time. Follow the basic rules of trading which is to buy low and sell high. Watch for things selling at a bargain that could possibly fetch a higher price later on because of an increase in demand.

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