The 10 Best Micrometers
10. Neiko 01407A
- shaft has a depth measurement probe
- very affordable price
- not very accurate
|Rating||3.9 / 5.0|
9. Absolute Origin
- connects to computers via usb
- backed by 2-year warranty
- fine-tuning knob can start to slip
|Rating||4.0 / 5.0|
8. Platinum Fractional
- case made of high-impact plastic
- three different-sized models
- lcd screen somewhat dim
|Rating||3.8 / 5.0|
7. Carrera CP8812-T
- thumb wheel fine-tunes the calipers
- auto-shutoff feature
- memory recall can be inconsistent
|Rating||4.2 / 5.0|
6. Disc Brake Gauge
- conical anvils can measure grooves
- range of two-and-a-half inches
- outside dimensions only
|Rating||4.5 / 5.0|
4. IGaging Large Display
- comes in storage case
- includes ball attachment
- zero- to one-inch range
|Rating||3.9 / 5.0|
3. Mitutoyo 500-196-30
- reads absolute or incremental sizes
- gauges inside or outside dimensions
- made by industry leader
|Rating||4.1 / 5.0|
2. Starrett T444.1 Ratchet-Stop
- satin-chrome finish resists rust
- comfortable and easy to handle
- locking spindle for stability
|Rating||5.0 / 5.0|
1. Mitutoyo 293-340-30
- great for professional applications
- rugged ip65 construction
- high precision for close tolerances
|Rating||4.9 / 5.0|
Engineering Precision On A Small Scale
Modern conveniences are oftentimes things we underestimate or take for granted when we're so used to their normal operation. When opening a refrigerator door, for example, the expectations are that the light comes on inside and that the food contained on its shelves will be cold. We don't necessarily contemplate the dimensions of the fridge's components or why they've been shaped a certain way.
It's easy to overlook the amount of engineering involved in the construction of such appliances. However, without careful measurements and consideration for the size of small components, appliances like the fridge wouldn't be able to do their jobs adequately. When it comes to mechanical engineering and the machining of small parts that require precise measurements, a tool like a micrometer will be able to deliver a significantly higher level of accuracy than an ordinary tape measure or ruler alone.
Similar in design and application to a caliper, the micrometer (also known as a micrometer screw gauge) is a tool that measures the depth, length and thickness of very small objects, depending on the type being used. Examples of the tool's application include measuring the thickness of a sheet of paper, a wire, the diameter of a hole, the length of a screw's surface, or the depth of a slot on a piece of metal.
A typical micrometer has a series of both stationary and moving components. The tool's thick, C-shaped frame contains all of the non-moving components, including the anvil, lock nut, and sleeve, while the mobile components consist of a thimble, spindle, and ratchet. In order to take accurate measurements, an object must first be placed between a micrometer's anvil and spindle. The thimble is then spun in one direction, moving the spindle either closer to or farther away from the anvil until an object has been gently pinched between the anvil and spindle faces. The lock nut prevents the spindle from turning. The sleeve is equipped with internal threads that allow the spindle to move, as well as a linear scale that will determine an object's measurements. Located at the end of the tool's handle, the ratchet is responsible for limiting the applied pressure from the spindle to ensure it doesn't grip the object too tightly.
Versatility is one of the tool's major benefits, particularly if it's a specialized micrometer that comes with interchangeable anvils or other components. Why is its level of precision so important? Because many everyday objects require a certain type of construction, thickness, or evenness throughout, the micrometer has been specifically-designed to detect these measurements to ensure a high level of accuracy when manufacturing small parts.
Making The Most Out Of A Micrometer
There are several practical considerations to keep in mind when investing in a micrometer to meet your needs, one of the most important being the tool's durability. The anvil should be made out of either hardened steel or carbide. Both materials are good for use in abrasive industrial environments and will stand up to years of heavy use. Insulated frames that resist excess body heat will also come in handy when trying to ensure measurement accuracy. A solution with extra padding can prevent the tool's components from expanding or contracting over time.
When precise readings are important in your line of work, spring for an option that includes an LCD screen. Aside from making measurements easy to see, the addition of a digital display will also help improve overall accuracy, particularly when it is equipped with a zeroing out function. A zero function allows the tool to automatically calculate differences between measurements, minimizing the need to work out those differences in your head or with a calculator. The inclusion of a digital readout is often accompanied by an instant unit conversion function that makes it easy to change between metric and Imperial measurements.
Depending on your trade, a specialized micrometer can come in handy when working with a variety of different objects of varying depths and thicknesses. One with interchangeable anvils, for example, will allow you to adjust the tool accordingly without having to purchase several types.
Measurement And Innovation Through The Ages
The evolution of the micrometer has a rich and deep-rooted history in terms of human innovation as it relates to the building of various objects. The concept of measurement in terms of machining and engineering dates back to the construction of the pyramids of ancient Egypt. Although the principle of screw threads was utilized by the Greeks to raise water from one elevation to another, it was not used for measurement purposes until the 17th century.
In 1638, English astronomer William Gascoigne used the concept of threads to measure the distance between stars by finely adjusting the screw threads of his telescope. By 1639, Gascoigne invented the caliper micrometer, which consisted of a rotating handle attached to the end of a threaded rod that was itself connected to a movable jaw. Measurements on this device were recorded by counting the number of revolutions the handle would make against an attached disc.
British inventor Henry Maudslay developed one of the first tabletop micrometers by the early 19th century, referred to as the Lord Chancellor, which marked the beginning of precision measuring instruments. In 1848, French inventor Jean Laurent Palmer received a patent for the first handheld micrometer called the System Palmer, known for its U-shaped frame after which many of today's micrometers have been modeled. By the end of the 19th century, micrometers were being mass-produced and used in machine shops in an effort to improve product quality by means of measurement accuracy during the manufacturing process.
Mitutoyo founder Yehan Numata is widely credited with the release of the first commercially-available micrometer in 1937, followed by an increase in production demand for the tool by 1941 for the war effort. The measuring range for the micrometer increased significantly by 1953.
Today's micrometers are available in standard and specialized types to meet the needs of any machining task.