CNC – Lathe spindle – what the innards look like
1: Spindle lock nut 2: Spindle 3: Double row cylindrical roller bearing 4,5: Headstock housing 6: Angular contact ball bearing / Taper roller bearing. Prevents axial movement of spindle. 7: Double row cylindrical roller bearing 8: Labyrinth cover 9: Spindle bore 10: Spindle
Data courtesy: Micromatic Machine Tools Pvt. Ltd.
Action point The accuracy and life of a spindle depend on the material, the accuracy of manufacture, and the quality of the bearings. A better spindle gives you better better quality of parts and higher machine life. A better spindle also costs more money. So when machine X costs more than machine Y although they are the same size, it is probably because X has better build quality. Keep this in mind when buying a machine, instead of merely deciding on the cheaper machine.
Somnolent scorpion on an evening walk
I was on an evening walk on a friend’s farm recently, and came across this scorpion basking in the sun in the middle of the road. I wondered what it was doing in daylight, because scorpions are nocturnal. Biggish fellow, but nowhere near the world’s biggest scorpions, that are about 30 cm (a foot) long.
I was reading somewhere that scorpions are one of the hardiest creatures on Earth. They can live in extremely harsh climates, and can slow their metabolism drastically when there’s no food available, surviving on just one insect for a whole year. There’s also the story of how researchers froze some scorpions overnight, then put them out in the sun the next morning, and the scorpions just unfroze and walked away.
The sting of the scorpion is meant to kill or paralyze prey. Scorpions are nocturnal to avoid being eaten by other predators. These predators include humans – fried scorpions are eaten in some countries. There are about 1750 species of scorpions worldwide, of which only around 25 are fatal to humans.
Coincidentally, as I was cycling to my office in Bangalore a few days later, I saw this funky scorpion on the side of a bus.