A global distributor of precision measurement tools


Yes. In fact, there are two main circumstances in precision measurement when you should not use a ball probe tip made of ruby. The first involves adhesive wear. Adhesive wear occurs when a ruby ball probe is used to scan aluminum and is caused by two materials having a chemical attraction. In order to avoid this, when scanning aluminum you should use a ball probe made of silicon nitride. The second circumstance in which to avoid ruby is when abrasive wear is a risk. Abrasive wear occurs when scanning cast iron and is due to the small particles that cause scratches on the ball probe tip. Zirconia should be used instead of ruby to avoid abrasive wear when scanning cast iron.

Calipers are used to measure the distance between two opposing sides of an object in a variety of ways. These great devices come in a range of types, with three very common versions—Vernier caliper, digital caliper, and dial caliper. A Vernier caliper is the most common of all, and the most precise. A Vernier caliper includes a built in Vernier scale, which is a visual aid that indicates specific gradations between measurement marks. Utilizing a Vernier scale for measurement allows for an incredible degree of accuracy. A digital caliper is distinguished by the digital readout screen that displays the final measurement after the caliper has been adjusted appropriately.

Finally, a dial caliper is built with a small dial in place of the Vernier scale. The dial is rotated when taking a measurement and the final number will be in millimeters or inches, as read along the manual scale provided.

Technically, no, they are not mandatory for making a measurement, and depending on your level of skill and need, you might only be aiming for accuracy and knowing that the measurement you have is close to the true value of what you are measuring. However, in order to have the best quality measurement, you do need both accuracy and precision. Just knowing the value you found is close to the true value is not enough when you require higher levels of measurement skill. You will also want a measurement system that is able to repeat those accurate measurements again and again, thus creating precision. No matter how simple or complex your measurement system may be, striving for both accuracy and precision ensures that you have the best measurements possible.

Yes, we have knowledgeable employees that are able to assist you with selecting the appropriate measurement tool for your application. Go to our Ask the Expert page in our Learning Center to e-mail us, or call 617-420-2517 and let us know a little more about your specific application. If it is easier to send a part drawing, feel free to e-mail it to us and we will get back to you as soon as possible.

There are two main references to set when using a height gage: the internal zero and the ball diameter. A couple of key checks to run initially when setting these references are very important. First make sure that the surface plate used to set the internal zero is completely clean of any debris or dust; same goes for the ball. Second, make sure that both the surface plate and the ball are securely attached to the height gage and not at all loose. Both of these could interfere with the precision of your measurements. In order to set the internal zero of the surface plate, lower the sensing head and touch it to the plate. This will then be your baseline zero for any further measurements. Setting the reference of the diameter of the ball is equally important. The standardized text fixture and routine that accompanies your height gage should be utilized to set this reference point. As an extra precaution, the process of setting each of these reference points could be repeated a few times to ensure precision.
A telescopic bore gage measures the size of a bore through indirect methods. Essentially, the telescopic bore gage is used to take the size of a bore, and then an external tool, such as a caliper or a micrometer, is used to measure the output of the gage. The head of the bore gage is extended at an angle within the bore and locked into place. The extended head is the part that is measured to get the final output. Very similar to inside calipers, which can also be used to measure bore diameter, telescopic bore gages have the added advantage of being able to be locked in place during the measurement process, thus ensuring higher accuracy. Telescopic bore gages are used by mechanics and anyone in metrology that needs to find the interior diameter, radius, or circumferences of a pipe or a hole.

The Vyndicator Wireless Test Indicator consists of a transmitter and a receiver. The transmitter uses an attached stylus to send signals back to the receiver through a microprocessor connected to a sensor. Another microprocessor is located in the receiver, which decodes the signals sent from the transmitter. All of these relayed messages contain information regarding any movement of the stylus. The receiver then displays decoded information on its OLED display in regard to these movements, allowing the operator to complete necessary adjustments. A horizontal bar across the bottom of the receiver display represents the amount of distance the stylus moves, supplementing the numerical information provided.

Hardness, strength, and toughness are very similar concepts, but come with important distinctions. Hardness is simply the degree of resistance to deformation. Alternatively, strength refers to the amount of elasticity and plasticity of a material. In other words, how much can a material temporarily change shape (elasticity) and how much can a material permanently change shape without any damage (plasticity). These qualities in combination make strength. Toughness, then, is the greatest amount of energy that a material is able to absorb before breaking. This is distinct from hardness because hardness references the amount of force that can be applied before a change in structure. Toughness has to do with how much energy can be taken in by the material before a fracture occurs, and is sort of the opposing feature to hardness.
The regularity for recalibrating a set of gage blocks is not standardized. However, overseeing entities, such as American National Standards in Dimensional Metrology (ASME) and Federal standards do suggest a particular period of time after which you ought to recalibrate your gage blocks. The higher the grade of your gage blocks, the more infrequently you can recalibrate them. Gage blocks with a grade of 0.5 or 1 will usually be recalibrated once a year or annually. Gage blocks with a grade of 2 or 3 are typically recalibrated semi-annually or as often as monthly. Once you reach the level of master blocks, since they are not used as commonly as other grades of gage blocks, the typical length of time between calibrations is about 2 years. As a general rule, the regulatory power for matters such as recalibration rests on the shoulders of agency inspectors, rather than the National Institute of Standards and Technology (NIST).
There are no set of rules or regulations that exist defining how often a gage needs to be calibrated. Ultimately, the frequency of gage calibration is up to the company or facility owner or manager. While some believe that annual calibration is a good rule to live by, there are resources at stake that must be considered. Calibrating one gage or multiple gages too often will waste a large amount of time and money. However, on the other hand, not calibrating a gage that needs it will result in poor accuracy. Calibration should definitely be done in regular intervals, but the definition of regular will vary based on the drift and use of a particular machine. Using historical trend analysis can help determine what gages require more frequent calibration and when to expect that they will need to be calibrated.

How often a gage is calibrated is completely up to the end user or their company. Most companies have to follow a specific calibration cycle set in place by their company or their customers. Higherprecision.com recommends having a gage calibrated at least once a year depending on how often the gage is used and how careful the operators are with the tools.

Sure thing! Distinguishing between accuracy and precision can be tricky, and it can help a lot of people to put these words into a real world context. Let’s use golf as our example. Now, if a golfer hits a ball and gets a whole in one, that shot was accurate. If he hits a ball and it lands a mile from the hole, then his shot was inaccurate. This is because accuracy means being close to the true value, or in our example close to the pocket. Now, if that same golfer hits ten balls and they all land in the same sand pit, then his shots are precise. However, these shots are not accurate, since they are not near the hole. If the same golfer hits ten balls and they land all over the golf course, then his shots are not precise. In order to be precise, the golfer must hit all of the balls into the same area, whether that area is around the hole or not. Finally, if our golfer hits ten balls and they all land in the hole or right around it, then he has shown himself to be both accurate and precise.

No. Accuracy is different from resolution and in precision measurement it is important to know what they both are. The resolution of a gage is the degree to which the output of measurement can be broken down, whether in decimal places, parts, divisions, or counts. The smaller degree to which a gage is capable of making a measurement, the higher its resolution. Alternatively, accuracy is how close the output of a measurement is to the actual true value of the measurement. In other words, the less error there is in a particular measurement, the higher the accuracy of that measurement. A high functioning gage requires both resolution and accuracy—you need one to have the other.

No. Precision is different from resolution, just as accuracy is. The resolution of a gage is the degree to which the output of measurement can be broken down, whether in decimal places, parts, divisions, or counts. Precision relates to the resolution, but takes it a step further. The precision of a gage is the smallest (resolution), true (accuracy) measurement that can be taken repeatedly and reliably. The more precise a gage is, the greater its ability to take finely-tuned and accurate measurements again and again. While a gage might take the perfect measurement once, what you really want is to be confident that the gage will take as close to the perfect measurement as possible, every time—this is precision.

Yes, there are many kinds of micrometers out there. Some are basic micrometers, while others are specialized micrometers for particular jobs or measurements. What makes each micrometer unique is the kind of measurement purpose it serves. Universal micrometers are built with parts that can be swapped out depending on the job at hand. Blade micrometers, pitch-diameter micrometers, bore micrometers, tube micrometers, and bail micrometers are just few examples of micrometers with specialized parts that identify them for particular measurement goals. Digit micrometers use mechanical digit markers that roll and tell the measurement, whereas digital micrometers have an internal encoder that reports the measurement on a readable screen.

It is completely normal for a micrometer to become un-calibrated. This is easily fixed by just recalibrating it. Often, you will be able to zero a micrometer by using a small pin spanner that adjusts the sleeve in order to realign its zero line with the zero line on the thimble. Once this adjustment has been made, you can double-check the accuracy of your micrometer by adjusting it such that the anvil and the spindle faces are touching, and seeing that the micrometer reads zero. Another way in which to test the accuracy of your micrometer is to measure a standardized item, like a gauge block or rod, for which you already know the exact measurement.

The resolution of your gage is pivotal to respectable measurement. In today’s world, technology is advancing at lightning speed. While there are bigger, more obvious ways in which this impacts the field of measurement, it also has a great impact on the smaller things too. The modern gage can be built to have an incredible degree of resolution. While a gage is used to conduct precision measurement on both small- and large-scale projects, this high resolution should never be sacrificed. The resolution of your gage is important in every practical setting because it directly impacts the accuracy of your measurement. Every project and measurement you take part in ought to value accuracy, and having high resolution is how this is done. No matter how basic the application, the technological advances that allow for incredibly precise measurement capabilities ought to be taken advantage of by all.

The TESA height gages by Brown & Sharpe are compatible with a number of different accessories. From panels and printers to probe holders, they come with it al. No matter the job you need to get done and the individualization your height gage requires, the Brown & Sharpe height gage can be built or adjusted to match. We have a number of probes with all sorts of fixations, shapes, and sizes. There are ball, disc, cone, shaft, cylindrical, and barrel probes. A special feature of the Brown & Sharpe height gage is its ability to measure both straightness and perpendicularity. You can easily attain these squareness measurements by utilizing the available accessories. Finally, the accessories come in different sets in order to maximize the efficiency of your purchase. The accessories that are compatible with Brown & Sharpe height gages reach far and wide. Call us at higher precision today to learn more about each of our height gage accessories.

The main advantages of the Fowler QuadraTest Electronic Test Indicator over older dial style indicators relate to the way in which the measurement data is recorded, stored, and transmitted. From the initial step of taking the measurement, the electronic indicator will give a precise measurement without risk of a human misreading the dial. That data point can then be transmitted electronically, further removing any possible error made by a person reading the number and transcribing it incorrectly. All of the data points measured by the electronic indicator are easily sent and stored on a computer, formatted for any analysis that will occur. All of this results in much faster measurements, guaranteed to be more exact. Finally, the Fowler QuadraTest Electronic Test Indicator has the capability to switch back and forth between metric and inch units. This prevents error and enormously speeds of the process of changing or updating the data. Overall, the digital test indicators exhibit an increased amount of control over the measurement process.

The micrometer is generally an excellent precision measurement tool. As with most things, the micrometer comes with some advantages as well as some disadvantages. Micrometers are one of the most accurate measurement tools available, measuring as far as the 100 thousandths decimal place on more advanced, digital models. The ratchet creates a uniform amount of pressure resulting in measurements that are both reliable and repeatable. The scales located on the sleeve and thimble of a micrometer function together, ruling out the need for external measurement tools. Also, micrometers exist in highly specialized designs allowing for even more applicability and precision. Finally, micrometers are built to be very durable. You will not break or wear these tools out quickly. As for the disadvantages, micrometers do have a naturally limited range. Bigger objects might require multiple micrometers or larger micrometers, which can get very expensive. Additionally, while the specialization of micrometers is also an advantage, needing a certain type of micrometer for different jobs makes them slightly less efficient. Overall however, micrometers are a requirement for any industrialist and are unmatched in precision.

Hardness can be measured in a number of ways, and often you will want to choose a particular measurement tool or scale based on the type of hardness you need to assess. We will review a few of the more commonly used tests. The Brinell Hardness Test applies a hard metal ball to the material being tested from a vertical angle, using a known amount of force, for a specified amount of time. The degree of hardness is determined from the pressure diameter and the force applied. The Vickers Hardness Test uses a pyramid-shaped diamond indenter to make an indentation on the test material. Hardness is then measured using the diagonals of the resulting indentation. The Rockwell Hardness Test uses a diamond cone or steel ball to make an indentation on the material being tested. A number is then calculated using the resulting depth.

Before the invention of the Vyndicator Wireless Test Indicator there were a number of cumbersome and dangerous jobs that can now be accomplished by this amazing measurement tool. These indicators can be used for standard quality control functions, to make sure that machines are well aligned. Beam deflections and shaft alignment can also be tackled by the Vyndicator Wireless Test Indicator. Machine debugging and repeatability, milling machine centering operations, and deep hole boring operations each come much easier with this useful tool available. Finally, the Vyndicator Wireless Test Indicator can even serve the purpose of replacing coaxial indicators.

Indicators are used in a number of different industries including machining, manufacturing, fabricating, and science. A Fowler QuadraTest Electronic Test Indicator might be used to assess run-out of an automotive disc brake, when working to fit a new disc. These indicators can be used to run quality checks regarding consistency and accuracy in manufacturing projects. Another application is initial or re-calibration of a machine before use in a production line, or testing accuracy of a tool in a tool production company. Also, many physics experiments and projects require the precise measurements offered by electronic test indicators.

If you are using an electronic height gage, it will be capable of transmitting measurement information to a computer. However, some height gages go beyond this maneuver and are hooked up to the computer through a wireless connection. For a successful wireless set up with your height gage, you need a transmitter and a receiver, just like you do for wireless internet. The major advantage of wireless communication with height gages is that it eliminates the nuisance of having a wire connecting the tool to the computer and getting in the way of the operator. One potential risk of working with a wireless height gage is that there may be signal interference, or a problem with the transmission of the measurement information. However, the modern wireless height gage is advanced to handle this risk and is well-equipped to protect against any interference. Additionally, wireless transmission eliminates possible transcription errors, keyboard mistakes, missing data, and any number of other manual issues with data coding.
The most important features of a ruby that make it the top-choice material for ball probes are 1) its resistance to abrasion and 2) its resistance to compression. A naturally hard substance, ruby is particularly tough when it comes to use in precision measurement. Knowing that your ball probe will not be damaged while conducting measurements is extremely important. The level of sphericity of the ball on a ball probe is crucial to the accuracy of the measurement. Any damage or warping that occurs will result in an unreliable readout. Ruby ball probe tips have incredible smoothness and are able to combat the damages that may occur with other materials.
The grade of a gage block is a specific rating given to the gage block that represents the degree of tolerance it has. Gage blocks used to come in grades depicted by letters – A, AA, AAA, B. Now the standard labeling is in the form of numbers ranging from 0.5 to 3. Each grade has a different purpose, but generally, the higher the grade, the tighter the tolerance. Tighter tolerances, and therefore higher grades, will result in a greater amount of accuracy and precision in your measurement. Depending on the country and the company you are working with there will be different ways to label grades. Higher grades, representing smaller degrees of tolerance (or higher degrees of tolerance tightness; ±0.05 μm) are often used to establish standards and calibrate, while higher grades, representing slightly larger degrees of tolerance (or lower degrees of tolerance tightness; 0.25 μm to − 0.15 μm) are used as shop standards for precision measurement purposes.

The probes available as accessories to the TESA height gage by Brown & Sharpe include ball probes, disc probes, cone probes, shaft probes, cylindrical probes, and barrel probes. The most common type of probe used with height gages is the ball probe. These come prepackaged with each height gage. Typically used in order to complete bore measurements or to probe centering shoulders and grooves, disc probes are excellent to have around. Cone probes are made to position nicely at the center of a bore and can be used to find their location. Measuring grooves, blind bores, and centering shoulders can best be accomplished by shaft probes. Finally, probes that are cylindrical or barrel in shape are ideal when measuring elements that are more difficult to tackle using a standard ball-shaped probe.

Calipers are capable of measuring in four ways: 1) outside diameter, 2) inside diameter, 3) depth distance, and 4) step distance. Whether you have a Vernier, a digital, or a dial caliper, you will be able to complete all four of these potential measurements. Outside diameter measurement assesses the distance from one edge of an object to another using the outside dimensions. Inside diameter measurement looks at the distance between two inside points of a space or hole. Depth distance measurement provides the distance to the bottom of a space or hole. Finally, step distance measures the distance between an upper and lower step of an object. Calipers are incredibly useful because they can accomplish each of these different measurements. These highly adaptable tools are a great asset to any precision measurement workshop.
The MIN and MAX readouts from your indicator are telling you the lowest and the highest point on the surface of your part, respectively. These measurements are determined by running the indicator across the surface of your part while rotating it along a centralized axis. The indicator will pick up on the points that are lowest and highest, allowing you to have a quantitative measurement of any discrepancies along the surface. These measurements are important for determining the flatness, roundness, concentricity, or any other intended shape. Once a part is made, testing the MIN and MAX of the surface is crucial to understanding if the part is shaped precisely the way it is supposed to be.
Ceramic gage blocks are a newer, but very popular option when compared to steel gage blocks. A few of the main advantages of ceramic gage blocks include the zero thermal expansion coefficient that ceramic has, the zero phase shift, and the resistance to corrosion. Due to these qualities, ceramic easily adapts to new temperatures, is not as impacted by risk of phase shift, and will last a very long time without damage from grit or humidity. In general, ceramic gage blocks are advantageous over steel gage blocks because they last a very long time without corrosion or damage. The main disadvantage of ceramic is that it is more fragile than steel. If being utilized in a context where there is risk of breakage, ceramic may not hold up quite as well. Ceramic gage blocks are an excellent choice, depending of course on your precision measurement needs.
Steel is the classic choice when it comes to deciding on a base material for your gage blocks. Steel has a distinctly hard surface and is therefore resistant to chipping or cracking. Additionally, this hard material will be protected during lapping and ideal for wringing. Another major advantage of steel gage blocks is that most industrial parts that will need to be gaged will also be made of steel. Therefore, steel gage blocks will very easily match the thermal expansion coefficient of the material being measured. The greatest disadvantage of steel as a gage block material is that it is not stable over time. While advances have been made, steel will expand over time due to the crystal makeup as well as the hardening process. Furthermore, steel is subject to corrosion caused by scratching or humidity and will likely rust over time. Steel gage blocks can be the ideal choice in a shop environment and are built strong depending on what you need for precision measurement.
The first level of electronic height gage functions very similarly to a mechanical height gage. They will have a comparable level of accuracy to a mechanical height gage. Additionally, these will include both a floating and an absolute zero, data output, and data unit conversion. The second level of electronic height gage builds upon the first group. This level will have an increased degree of accuracy, and might possibly come with more advanced features. Some of these features could include a tolerance setting, a maximum and minimum setting, TIR compensation, ID/OD measurement, or a probe compensation. Finally, the third level of electronic height gage contains all of the features of the first and second level, with higher accuracy and more features. The additional features you will likely see in this group are a motorized touch probe, a computer interface, air bearings, and the ability to store part programs.
Hardness in general is the amount of resistance a material has to any kind of deformation from an outside source. The three main types of hardness include: indentation hardness, scratch hardness, and rebound hardness. Indentation hardness is the resistance a material has to deformation from a consistently applied force. The higher the indentation hardness, the greater ability to not have any resulting deformation from applied compression. Scratch hardness is the degree of resistance one material has when it is subjected to friction caused by another material. Materials that are less impacted by this scratching will have higher scratch hardness. Finally, rebound hardness is the amount of bounce that occurs when an outside object is dropped on the material in question. Often tested with a diamond-tipped hammer, a material with higher rebound hardness will lead to a higher bounce when the hammer is dropped.
The standard IP rating consists of two numbers. Each of these numbers represents a specific level of protection. The first number in an IP rating represents the level of protection against solid ingress, while the second number represents the level of protection against liquid ingress. As a general rule, as each of these individual numbers increases, the amount of protection goes up. The IP rating for solids increases on a scale from 0 = No protection to 6 = Total dust ingress protection. The IP rating for liquids increases on similar scale from 0 = No protection to 8 = Protected against continuous immersion to a specified depth or pressure. Different factors to consider when choosing an IP rating include the context of the work you plan to do, what length of time you will need high or low levels of protection, and what debris or accidents could occur at the worksite.

That the Fowler zCat DCC CMM is direct computer controlled means that all of the features and capabilities of the CMM can be controlled by and recorded in the connected computer. The advanced technology of the zCat allows for direct communication between the tool itself and a computer through a wireless connection. The machine can be operated through the computer, or previously manual operations can be stored and repeated through the computer at a later time. Furthermore, all measurements captured by the zCat are swiftly and automatically transferred into the computer and stored in an Excel spreadsheet. Every Fowler zCat comes with built in ControlCAT software that performs all of these functions. The ControlCAT software is easy to use and operated by the touchscreen interface built into the zCat.

The Vyndicator Wireless Test Indicator comes with a wide breadth of features. To start, the wireless remote reading of this tool makes it stand out from its competitors. The first of its kind, this indicator seamlessly transmits measurements to the receiver wirelessly, making reading the movement of the stylus easy. The receiver provides read-out in most English and Metric modes, using a bright OLED display that is easy to read. The mounting VEES is the standard in precision measurement industry, and this indicator operates on batteries. The measure modes include Standard, TIR, Low and High, and this handy little tool is capable of using multiple units in the same area. There is a moving bar on the receiver that shows any stylus movement, and the stylus itself is reversible and comes in 4 different lengths.

The TESA Micro-Hite height gage by Brown & Sharpe is used in all kinds of metrology and a number of different industries. Mainly, these include automobile, moulds and tooling, medical, or plasturgy industries. In the automobile industry, height gages might be used to measure injection systems, brake systems, or engine components to ensure quality and precise design. The complexity and exactitude involved in moulds and tooling requires an excellent machine such as the Brown & Sharpe height gage. These height gages are vital to measuring various molds and tools that are then used to create millions of copies of different foods, aeronautics, cosmetics, etc. The standards set within the medical field are very high, and the controlled nature of medical devices and tools is very strict, since their eventual use involves high risks and high rewards. Brown & Sharpe height gages are built for excellence, and come equipped with the high-level analytic capabilities, regulatory compliance, and measurement precision that are imperative to the medical industry. The variability of plastic development and the regularity of product within the plasturgy industry is the perfect place to see the Brown & Sharpe height gage shine. This tool has the validity and stability that is essential to all processes in working with plastics.

A coordinate measurement machine, commonly abbreviated to CMM, is a measurement tool that takes a geometric reading of an object using a probe that senses the angles and points that make up the object. The probe on a CMM can be one of many types including white light, optical, laser, or mechanical. Furthermore, the probe on a CMM can be either manually or computer operated. On the Fowler zCat DCC CMM, the probe is both manually and computer operated and transitions smoothly just by how the operator decide to use it. Most CMMs utilize the Cartesian coordinate system to determine the discrete points on an object. This movement along the X, Y, and Z axes helps to create a precise three-dimensional model of a part.

The zero error on a caliper has to do with the baseline point of the caliper. If properly cleaned and closed, a caliper ought to measure 0.00 exactly. Occasionally, this will not be the case and then you have a zero error. A zero error on a caliper can be positive or negative in direction. A positive zero error occurs when the caliper jaws are closed, but the readout has some positive value, whereas a negative zero error occurs when the caliper jaws are closed, but the readout has some negative value. This can occur when a caliper is not properly maintained, or after normal wear and tear from use. No matter the cause, a zero error occurs when the caliper is not properly calibrated to the zero point. Knowing if your caliper has a zero error is extremely important for the accuracy of your measurement. If there is any discrepancy in the calibration of your caliper, you must then account for it in your final measurement.
While different experts in the field of metrology have differing opinions on how often gages need to be calibrated, one thing is agreed upon—there must be some sort of calibration schedule. One potential solution to regular gage calibration is to create a gage control program. Very simply, a gage control program is a systematized way to determine how often a gage requires recalibration. The central goal of a gage control program is to create a document that names each gage, records the intervals of calibration, and classifies the gage within a bigger system of groups defining when calibration will occur. This document then allows you to see when a particular gage was last calibrated, how often it has been calibrated over time, how frequently it is utilized, and who is charge of maintaining its use.

The repeatability measured by a gage R & R study refers to the variability in measurement which results when one individual measures one part using one gage. In other words, when one operator measures one part using one gage again and again, the resulting changes in measurement are due to an error that is occurring within the equipment. While infinitesimal repeatability issues are going to be expected, a gage R & R study can root out more serious inconsistencies. Testing repeatability is an important part of gage R & R studies, and it is what tells you that your gage is imprecise and requires attention.

The reproducibility measured by a gage R & R study refers to the variability in measurement which results from the irregularities of the operator. Reproducibility is tested by having multiple individuals measure the same part using the same gage. In this way, a gage R & R study can adequately determine if there is variability due to the individuals measuring the product, rather than the measurement process or equipment itself. The reproducibility is necessary to know how much variation results when different operators use the same equipment. Just as it is important to know that your equipment is functioning well, it is necessary to know how individuals are impacting the measurement process of a larger manufacturing system.

The Coefficient of Thermal Expansion, also known as CTE, is the degree to which a given material expands when it is heated. Depending on what material you are working with, that material will have a specific CTE that differs from other materials. When heat is applied to a substance, the distance between the individual atoms that make up that substance increases. This leads to an overall expansion of the material dependent upon the number of atoms involved, and therefore its size. Knowing the standardized CTE of a material allows you to account for any expected expansion when conducting measurements or using the material to build parts.

Small hole bore gages come in two main types: full-ball and half-ball bore gages. The terms full- and half-ball refer to the end of the bore gage that is inserted into the bore to complete the measurement. This end is typically opposite to the knurled knob used for setting the anvils. Full-ball small hole gages are generally simpler to set the anvils on and lock into place. More often than not, these bore gages will provide a more accurate and precise measurement of a bore. Half-ball gages are more prone to springing during measurement and require a more experienced user. Half-ball bore gages are more likely to result in an inaccurate measurement. However, some machinists prefer half-ball bore gages because they allow the user more control and leave room for adjustment in unusual measurement circumstances.

The total indicator reading (TIR), sometimes called total indicator run-out (TIR) mentioned for the Fowler QuadraTest Electronic Test Indicator refers to the difference between minimum and maximum measurement. In other words, the TIR measures the amount of deviation from whatever the targeted structure is (flatness, concentricity, cylindricity, roundness). The TIR is the value measured about a particular reference axis. TIR is highly important in preventing excessing stress, premature wear, and a failing system. This is because TIR assesses whether the central axis that is being measured is unequal in direction and/or angle.

A ball-tipped probe is most often used to assess the flatness of a surface, also known as scanning. By using a ruby ball probe, you are harnessing each of the advantages of ruby as a material—sphericity, hardness, smoothness, and resistance. Scanning is used in order to identify any flaws that a material might have. A ruby ball probe is used to measure the individual imperfections that are found during the scanning process. By running the probe across the surface of interest, you can find and measure the size of any flaws that exist. Ensuring smoothness and perfect sphericity of the ball on your probe is pivotal to successful scanning. Ruby is the best choice for this purpose since it is reliably spherical and smooth, as well as difficult to damage.
The IP rating, or protection level, that you need will vary from job to job. What is most important is knowing the context you will be using your gage in and then deciding the degree to which you require protection, and from what specifically you want to protect your gage. Some precision measurement contexts will involve high pressure water tools and you will want a higher number IP rating to account for this. However, others might involve no risk of water being nearby, but be in a setting with a great deal of construction that will lead to accumulated dust. You will need to focus on a higher first digit in your IP rating for this purpose. Finally, there is a certain amount of protection that you can strive for concerning potential risks that may or may not happen. For example, there might not be water directly in the vicinity, but there might be a sink nearby that runs the risk of overflowing with regular use. Alternatively, the area where your gage will be used might not be scheduled for regular cleanings, or not be cleaned until the end of the project, so you will want to account for potential dust build up. There are many moving pieces to each precision measurement context, and you will want to know the specific risks you have to determine the best IP rating.
The main qualities that you will want to consider when deciding on what material gage blocks to purchase include dimensional stability, accuracy, thermal conductivity, and hardness. Dimensional stability refers to how much a material changes in size over time. Through use and environmental changes, some materials are more susceptible to changes than others. Accuracy is the degree to which a material can be made more precise through flatness, parallelism, and the finish on the surface. Thermal conductivity relates to the coefficient of expansion of a material and refers to the ability of a material to move to the same temperature of another material. This is important, for various industrial parts will come with their own coefficients of expansion. Finally, hardness is the quantitative degree of resistance of a particular material. Depending on its grade of hardness, a material will be more or less resistant to wear or abrasion.
Human error is unavoidable in any profession. Similarly, in precision measurement, the height gage operator is a crucial factor in its accuracy and success. This is particularly salient when an operator is working with a manual height gage. The speed and pressure with which a part is touched onto a height gage can significantly alter the outcome of the measurement and introduce variability. Due to this potential for error, operators must go through very regimented and precise training in order to properly learn how to operate a manual height gage. The icons on a height gage have been specifically developed to be intuitive and instructive for use in order to aid the operation of the height gage. Finally, the more electronic the height gage, the less pressure that falls onto the operator, resulting in the minimization of error in accuracy due to operator involvement.

The Fowler zCat DCC CMM is the top notch CMM device available in the field of precision measurement today. The most distinguishing feature is its portability. The Fowler zCat weighs only 30lbs and runs on the included 10.8-volt lithium battery for up to 4 hours. Unlike any other CMM available, these features make it simple for you to bring your zCat to any part that needs to be measured rather than having to bring the part to the CMM. Additionally, the entire design of the Fowler zCat was created with the user in mind. Intended to be simple to use, the zCat has intuitive controls and a basic interface. Easily switched from computerized to manual, the zCat offers the best of both worlds for anyone that needs both functionalities. Finally, the Fowler zCat comes built with ControlCAT software, a specialized programming software made just for the zCat that is simple to use and incredibly precise.

Micrometers are certainly built to last, but that does not mean that you should skip these quick and simple steps to make them last even longer. First and foremost, take care to not drop your micrometer, or slam it down on any surface. This could impact its measurement accuracy. If you do accidentally drop it, make sure to recheck the calibration before using it for measurements. Another important habit to develop is to wipe down your micrometer on a regular basis. Particularly, you want to wipe the measurement faces in order to ensure that no dirt or build up impacts your measurement. Use a dry, lint-free cloth to do this. Also using a lint-free cloth, wipe your micrometer with a very small amount of oil after long periods of non-use or storage. This will help to avoid the build up of rust or other corrosive mater. When storing your micrometer, keep it in a place that is as close to room temperature as possible, with as low humidity as possible. This will help prevent warping of any sort. Finally, when your micrometer is not in use leave a gap between the anvil face and the spindle face. Prolonged contact between the two faces could lead to a less accurate measurement.

Finding reference tables containing the specific Coefficient of Thermal Expansion (CTE) for various materials is not difficult. However, there are two important features to remember about the principles of the effects of temperature on materials when utilizing these resources. First, there is no way to account for a guaranteed amount of uncertainty that is built into these tables. The original measurements used likely had a certain degree of human and machine error, and there is a natural discrepancy of CTE even between different pieces of the same material (even from the same manufacturer!). Second, the reference tables for CTE that you will find more often than not report a range of temperatures for which a specific CTE applies. This is somewhat unreliable should you be taking a measurement at a very precise temperature. While the CTE reference tables are a great resource, it is important to keep these warnings in mind when using the values for precision measurement.
The MIN, MAX, and DELTA (or TIR) measurements are important for ensuring that the part you have made is precise enough to function properly. If you are building a part that will need to work as just one piece of a bigger mechanism, then you will need that part to be the correct shape with the correct surface structure. Using an indicator to measure the MIN, MAX, and then the corresponding TIR will help you to do this. For example, if you are building an axle that will be used in a bigger machine that produces parts for space shuttles, you need that axle to fit precisely where it needs to in the bigger machine. Additionally, you want to ensure that over time, the surface of that axle wears evenly rather than unevenly, as uneven wear might disrupt the functioning of the machine and the corresponding parts it produces.

A man named William Gascoigne invented the very first micrometer in the 1600s. This micrometer was used to measure the distance between stars through a telescope, and to estimate the size of various celestial objects. Later, in the 1800s, Henry Maudslay upgraded the micrometer to a version built for mechanical use. This tool was made to be durable as well as accurate. Then, later in the 19th century, Jean Palmer created a handheld version of the micrometer, making it much more accessible and popular in industrial fields. The micrometer at the time represented an excellent pairing of technology and science. Today, the micrometer remains one of the most important tools in the industrial world, having many applications and reporting consistent and trusted measurements.

Both accuracy and precision are equally important in order to have the highest quality measurement attainable. For a set of measurements to be precise, there is no requirement that they are accurate at all. This happens because as long as a series of measurements are grouped together in value, then they are precise. However, there is no rule that the value they are grouped around needs to be close to the true value of the item being measured. Because of this, sometimes accuracy is valued over precision, simply because it can be more useful in determining the needed value. However, when maintaining a measurement system, the system must be checked regularly for both accuracy and precision, since they are both equally important for measurement success.

Gage calibration can be done by the owner or facility manager him or herself, it can be outsourced to a commercial calibration service, or it can be done by the original manufacturer who built the gage. There are pros and cons to each. Doing the calibration in-house can be a huge investment to set up the facilities, but can also save time and money. Outsourcing can guarantee that specialists complete the calibration, but can lead to long turnaround time. Going back to the manufacturer ensures that the gage is in the same setting it was originally built and tested in, but can also add to the time or cost of moving the machine. Usually, gage owners will use a mix of these three options dependent upon the work that needs to be done and the speed with which it needs to be done.

The type of bore gage required will vary depending on the measurement job at hand, as well as on the preference of the user. Dial bore gages are often an excellent choice when needing to conduct a highly precise measurement of a bore. The biggest benefit of the dial bore gage is that it does not require the transferring of the measurement to another tool (micrometer or caliper), but rather has a built in mechanism so that a bore can be measured directly. In general, dial bore gages are both highly accurate and highly fast. Additionally, a dial bore gage comes in handy if the user needs to assess a bore for wearing or tapering that could impact the roundness and symmetry of the bore. Dial bore gages come with a very high resolution, usually reaching an accuracy of 1/100 of a millimeter or 5/10,000 of an inch.

Essentially, the total indicator reading (TIR) and the full indicator movement (FIM) measurements are different names for the same output. Both of these terms are assessing the degree of difference between the highest and the lowest point on the surface of a part. The subtle difference between them is that TIR relies on the readout of MIN and MAX from an indicator, whereas FIM relies on the zero cosine error and thus provides a slightly more accurate depiction of the actual movement of the indicator along the surface of the part. Both of these terms refer to the discrepancy along surface smoothness and shape, and can be used for similar purposes. The biggest reason that both terms exist is likely a delay in updating both professionals and materials. Most engineers today were educated using the term TIR and the majority of paperwork in the field still uses TIR terminology. FIM is a newer term and will take some time to become the standard in the field.

Gage R & R studies are vital to determining the amount of variability within a measurement system. Knowing the magnitude of the variability within a production line allows you to ensure that your measurement system is running smoothly and producing accurate results. In the world of precision measurement, exactness is everything. Should you find after completing a gage R & R study that the variability is too large, you would know for sure that you could not use your system as it is, and that you need to adjust it in some way. Knowing that there is an issue is the first step to fixing it, and making you a better manufacturer. Constant vigilance with the accuracy of your measurements can be accomplished using regular gage R & R studies.

Temperature is extremely important in the field of metrology. From minor measurements to determine the length of a car part, to major measurement projects like building a piece of an aircraft, the effects of temperature on material must absolutely be understood and accounted for in every measurement. Depending on whether a measured material will be exposed to an increase or decrease in temperature, the material will experience some degree of expansion or shrinkage, respectively. When you are measuring the material you will use to build a part, or measuring a final product, you must account for variances in temperature that naturally occur between the lab, the workshop, and the real world. In a field such as metrology, exact precision is everything. If you are going to get precise measurements, you must fully understand the role of temperature.
An IP rating is an extremely important factor to consider when purchasing a gage. While there are circumstances where the precision measurement environment you will use the gage in is relatively controlled, you always want to know the degree to which your tool is protected. There will be a variety of needs for protection, and you will not necessarily require the highest level. However, knowing what level of protection you do have available can save you time and money. There are a number of different and unexpected circumstances that can happen to a tool when it is in use. Perhaps you need your gage for factory work and you know that the climate is controlled and clean, and there should be no risk of dust or water in the area. However, what if a pipe bursts in the wall of the factory, or someone forgets protocol and brings in dust particles from another project. While you cannot protect against every possible scenario, you will want to use the IP rating of your gage to your advantage to determine what level of protection is necessary.
Knowing the tolerance of your gage blocks, or their grade, is an important tool to simplify the process of using them. Essentially, the tolerance is a way in which to classify how accurate your gage blocks will be. When calibrating a fixed gage, you might normally need to know the tolerance to stay within the required accuracy. The grade, or tolerance level, of your set of gage blocks helps to standardize this process and ensure that the µm is where you need it to be in order to perform the calibration. This eliminates the need to calibrate the length of the block stack from the calibration report. Various grades, or tolerances, are used for various calibration and precision measurement purposes, but as long as you know the tolerance of your gage blocks, you are at an advantage.
Live Chat
Cart Summary