Propano-butane mixture, which is filled in cylinders for household gas stoves, in optimal conditions, burns in air with a flame temperature up to 1200 °C. It is sufficient to work with “hard” (sredneivkino) alloys: copper-zinc (brass), silver. But to get a flame, the burner must provide good mixing of gas with air, that is, feeding them at a specific ratio — no more and no less! For easy work with small parts torch should be fine, but at the same time steady and fairly hot.
BOLT INSTEAD OF KEY
In modern household appliances, sanitary wares found a lot of threaded connection parts with hexagon sockets for the key. If necessary to disassemble a node with such parts is not at any DIY tool in the Arsenal of the right hexagon. But the bolt and the corresponding socket and a pair of nuts to it Read more…
Modelist-KONSTRUKTOR No. 4, 2012.
In the early XIX century the French scientist Augustin Jean Fresnel has created an unusual lens, which are not brushed solid piece of glass with a spherical surface, and a set of individual adjacent to each other concentric rings of small thickness, having a cross-sectional shape of the prisms of the special profile. This he achieved small thickness and light weight lenses. Fresnel lens in the past, have found application mainly in large lighting fixtures type marine beacons and today is actively used, for example, in projectors, in viewfinders of cameras and flashbulbs. Small thickness of such a lens allows you to release them in the form of plastic transparent rulers bookmarks, which are usually used by people with low vision read small text.
Not so often, unfortunately, in the magazine there are descriptions of the improvised structures that exceed the current level of production of the Russian, and especially Western technology. And this is understandable: after all, do these Amateur machines, usually in a shed or garage where all the equipment consists of a drill and a welding machine.
The ventilation needs of many suburban buildings. Without it, mold in houses and sheds, get wet cellars and basements, and only use luftblasen, where there is no fan, to put it mildly, uncomfortable.