Ceramic bearings are being seen about bicycles and additional hobby equipment, such as fishing reels, slot cars, and roller blade wheels. Ceramic bearings can be purchased in most sizes of bicycle cartridge bearings. The cartridge bearings generally use steel inner and external races, with ceramic bearings between. Ceramic bearings may also be bought as loose ball bearings .
The ceramic bearing has found uses in professional applications where there is great speed, great load, and, consequently, temperature. Bicycle riding easily does not cause high load, velocity or temperature. A bike going at 80 kilometers per hour (about 50 mph), will have hubs that rotate about 11 revolutions per second. An engine crank shaft, however, may turn at over 100 revolutions per second.
The standard of bearing could be identified by various ratings, such as the rating of ball roundness. A high quality steel ball bearing can be consider quality 25. The grade number refers to the tolerance per millionth of an inches. A grade 25 is exact to 25/1,000,000 of an in .. Less expensive ball bearings could be quality 300, which are a smaller amount rounded, at 300/1,000,000 of an inch. Ceramic bearings could be grade 5, that is a rounder ball bearing. The need for roundness, however, should not be overrated, as the bearing areas the balls operate on happen to be unlikely to always be as accurate as the grade of the ball bearing. The ball bearing is normally not the “weak hyperlink” in the machine.
Another aspect of the bearing is the property of the materials. There is a score for hardness known as the Rockwell level. Steel uses what’s called the Rockwell C scale, and ball bearings happen to be of course hard. This hardness permits them to rotate rather than wear, at least for a while. The bearings areas of the hub cone and cup routinely have a Rockwell C score of 55 to 60. A metal ball bearing may very well be over a Rockwell C of 60. A ceramic ball bearings can be a Rockwell C of 75, much harder compared to the steel races. This should provide good dress in features for the entire bearing system, not simply the ball bearing itself.
The top finish of a bearing is also important. Ceramic bearings aren’t necessarily smoother than steel balls. In the picture below, a Grade 25 metal bearing is magnified 200 circumstances . Grind marks are apparent. In the next photo, a ceramic bearing also show grind marks .
The ceramic material used in a ball is constructed of a grain structure, similar to a steel ball bearing . A significant property of any material is “stiffness.” This is a measure of how it deflects under tension or load, and the ranking of this property is named the “Modulus of Elasticity.” A metal bearing will be perhaps 30,000,000 pounds per square in .. Ceramic bearings made from silicon nitride can have a Modulus of Elasticity of 47,000,000 pounds per square in .. This extra stiffness means the balls will deflect a lesser amount of under load which will transfer energy better, proving a (tiny) savings. As the ceramic ball is approximately one-half the weight of a steel ball the same size, it is the stiffness that is important within their performance.
It conditions of Steel Ball Bearings service, there is absolutely no exceptional procedure or process. Bearing can be cleaned and lubricated as regular. Loose ball bearings will be installed and adjusted as with steel balls. Install bearings and completely cover with grease.
With cartridge bearings, it is possible lift the seal and check the grease. Remove the spindle or axle 1st. For many cartridge bottom level bracket bearings, it’s important to carefully remove the a plastic-type shield over the bearing. Use a seal opt for to lift the rubber seal from the interior edge . Wipe the bearing clean with a rag and add grease. Press seal into place.
Build a Basic but Fun Magnetic Gauss Gun a.k.a. Magnetic Rail Gun
The 3 items you will need are Cylinder Neodymium Magnets, Metal Balls and PVC Conduit for the road of the gun.