Q:I'm talking about another thing

Screw is the use of objects of the circular circular rotation and friction of the physical and mathematical principles, step by step to fasten the tools of the tools. Screws are the general terms of fasteners, daily oral language

Q:Who knows who invented the screw?

The spirits were invented more than 2,000 years ago, but less than 500 years for fixing things. The first person who describes the spiral is the Greek scientist Archimedes (about 287 BC - 212 BC) The Archimedes spiral is a huge spiral in a wooden cylinder used to The water is raised from one level to another, and the fields are irrigated. Its true inventor may not be Archimedes himself. Maybe he just described something that already existed. Perhaps it was the ancient Egyptian craftsmen who had designed it to use the irrigation on both sides of the river. Archimedes spiral in the ancient society are used to raise water, no one considered to change it into a fixed piece. Archimedes spirals are widely used for water lifting. For example, the Romans used it to drain the mine. In the Middle Ages, carpenters used wooden nails or metal nails to connect furniture and wooden structures. In the 16th century, nail workers began to produce spiral nails, these nails can be more firmly connected things. It was a small step from this nail to the screw. At the end of the eighteenth century, screws were quite popular as fixed parts, because at that time a cheap production method had been found. Screwdriver (chisel) appeared in London around 1780 years. The carpenter found that screwing the screw with a screwdriver was better than a hammer and could fix something better, especially when a fine screw was encountered.

Q:Screw hole slip wire how to do?

Slippery wire that has been broken thread, once the damage is not possible to repair

Q:Is the tail screw? If it is mainly used in what place? If not what are they different?

This kind of screw called what I really do not know its name, the use of the place to see really not much, I see the place are generally used in machinery and equipment above, as you said what role, my personal point of view is To prevent slipping, because it is the head of a large slip wire, need to hand to adjust to the correct position to fall off, know that so much, not professional, Oh ~ hope to help you! The

Q:Also known as screw nails, I want to nail on the board, but there is no way to nail into the hard, how nail?

Wood must use a self-tapping screwdriver, if it is a common machine above the screws can not be nailed to the board above, if the wood is relatively hard, it is recommended to use a drill above the board to play a smaller hole than the self- , So more effort

Q:I would like to know the specifications of the two types of screws models, including length, diameter, diameter and pitch, etc.

M3 means that the large diameter (external thread is the outer diameter) is 3. Of course with M3 nut, the length of a move does not include the nut. Thread section length is also another specification. M6 indicates a nominal diameter of 6 mm and indicates that it is a standard pitch coarse thread.

Q:Was rusty rust, the screwdriver are turning how to do, is a very important thing

Burning: some screw embroidery is very serious, with the above method is still ineffective, you can use the "fire attack." Put the screws and nuts thoroughly with gas oxidation flames, then drop a few pieces of oil into the red screw. The purpose of the heating screw is to heat the screws. The purpose of the drip is to quickly shrink the screws cold, increase the gap between the screw and the nut, the oil into the back nut can be unscrewed. But if there are plastic devices near the use of this method

Q:How to remove the broken screw?

Thick (5 or more) easy to handle, playing a hole with a dedicated wire on the line. Fine can be trouble, it is better to just re-drilling tapping.

Q:Screws, bolts, screws, what is the difference between the three ah?

There are no hexagonal head but the middle of the screw with the middle of the pole known as the double-headed bolts (studs), the whole body is screw called screw, in addition to countersunk head neck bolts, T-slot bolts, anchor bolts, U-shaped bolts. Bolt tightening device for the torque wrench, the opening size of the various shapes of fixed wrench, the opening variable size of the movable wrench, hydraulic tight bolts need hydraulic pumps and other accessories. In short: fasteners with screwdrivers and hexagonal tools are screws, and fasteners with wrenches are bolts. Note: can not be distinguished by the size and length of the nominal diameter. For example, a M48 long 300mm cylindrical head fasteners, GB / 70.1-2008 standard will be defined as hexagonal head screws, not bolts.

Q:How does the screw twist?

For the hexagonal head of the screw can be directly vibration (pay attention to strength), and then twist; if not edge of the case, you can use the saw or flat shovel of the head of the screw slotted with a screwdriver.