Parallel versus Tapered Threads

Threads

Limescale Removal

Calcium carbonate (limescale) dissolves in a range of mild acids.

Rust and WD40

WD40 stands for Water Displacement, 40th attempt (name used by the chemist who developed it in 1953). Norm Larsen was trying for a formula to prevent corrosion, achieved by displacing water. WD40 has no expiration date. It also cleans and degreases and can be used to lubricate the chain on a bike. WD40 cans contain carbon dioxide as a propellant.

You can remove rust with a wire brush and coat with WD40 to prevent rust.

Soap

The earliest evidence of soap-making comes from Ancient Babylon around 2800BC. A formula for soap consisted of water, alkali and cassia oil ("false cinnamon"). Recipes for soap have existed through the centuries. Only till about the 1850s did industrial production of soap commence. The Latin word "sapo" means soap.

Industrial Uses of Gold and Recycling

Gold has some useful properties that make it usable in electronics. Gold is highly conductive (lots of free electrons) and also resistant to corrosion and oxidation. Some people have tried to remove gold from household electronics.

Some experiences:
"I am using nitric acid and getting a good amount of what looks like gold"

What is Chicken Stock?

Chicken stock is the remaining water in which you boiled chicken, containing fats and oils. Sometimes used to cook rice.

Rowing Machines

Rowing machines, intended to simulate the sport of rowing, come in many shapes and sizes. The most common ones use "air pressure". They tend to be fairly noisy. You also get rowers with water resistance or magnetic resistance (the most quiet). You should always warm up before using the rowing machine, including lower back exercises. When rowing keep your back straight. Rowing hard at high resistance will increase shoulder size.

Games Hardware: PAL versus NTSC (and SECAM)

Game Territories

The PAL video game territory includes: most of Asia, Australia, South America, Africa and most of Western Europe.

NTSC is used in US, South Korea, Japan, Taiwan, Burma. Japan uses a modification called NTSC-J. NTSC = National Television System Committee. NTSC-C was a "region" created by Sony in 2003 for the release of its PS2 console in China.

Region lockout can make a game intended for one region unplayable in another region. Nintendo was the originator of region lockout in the video game industry.

Short History of Video Broadcast Standards

France still uses the SECAM standard which will be phased out in 2011. SECAM was introduced in 1967 in France to broadcast colour television, on "la deuxieme chaine". The PAL (Phase Alternating Line, 625 lines per frame) standard was introduced in the early 60's and implemented in most European countries (except France). A wider channel bandwidth than NTSC which allows for better picture quality.

What are Maltodextrin, Aspartame, Oligofructose?

Dextrins are carbohydrates produced by the hydrolysis of starch. They are produced from starch from enzymes such as amylases (similar to what happens in human body).

Aspartame is a sugar substitute (E951). It was first approved by the US FDA (Food and Drug Administration) in 1980.

Oligofructose is contained in some flavoured yoghurts. It is a healthy way of sweetening food and drinks - it's useful for people on calorie controlled diets.

Snow Chains

Snow chains are devices fixed to tyres to improve traction when driving through snow or ice. Driving with chains will reduce fuel efficiency and limits speeds to 30mph.