Why Do Linear Drives Require Force Measurement?

Force Measurement

Many industrial processes are switching to linear drives as opposed to pneumatic and hydraulic drives. With this change, it is becoming harder and harder to measure pressure. However, there are alternatives that give machine operators hope. Force measurement is now increasingly relying on force transducers and sensors to measure force. This is because it is impossible to use pressure measurements to take force measurements in a pneumatic unit. First, however, let us understand the basics.

What is a Linear Drive?

A linear drive is a system that creates translational movements. In such a system, the machine elements are driven in a straight line. Linear drives are simple as they use modular systems but can be adapted to fit the needs of the client. They also have the additional advantage of being very versatile.

Understanding Force Measurement

Force is any interaction that changes the direction that an object us taking on condition that is process is not opposed. Objects that have mass can have their velocity changed including objects that were at rest. There are two main ways force is applied namely as a push or as a pull force. One feature of force is that it also has a magnitude.  This refers to how much force is applied to the object. It also has a direction and thus a vector unit.

Why Force Measurement?

Having linear drives offers the opportunity to measure forces directly during the process. Whether the transducer is linked to force flow makes no difference. The transducer can be on the actuator, the motor or even at the point where the force is applied. The reliability of the tests will still be highly accurate. Force measurement is critical in all sorts of applications. From machinery that produce our consumer goods to some of the products, we use ourselves. A good example of force measurement in everyday products is when it comes to springs. These are used in a variety of products including ball pens, automobiles and much more. The ability of these products to work well is dependent on how well force is applied by the springs that are in the product. Quality control experts must carefully measure the force that is released by the springs as it determines the functionality of the products.

Real-Life Applications for Linear Drives

Linear drives are found in a variety of applications. These range from material handling, as well as robotics. They are also found in food and beverage industries as well as agricultural machinery. Manufacturing facilities, especially those that utilize heavy-duty ventilation systems use electric linear actuators to open and close the heavy ventilation systems. Solar farms that have hundreds of large solar panels also utilize linear actuators to tilt the panels. This, in turn, allows for the panels to get maximum exposure to the sun. Without the ability to measure how much force these systems are putting out; it would be very hard for their operators to monitor their performance.

For the best in precision instruments, get in touch with Willrich Precision. We have years of experience in delivering great products to customers all over the United States.

Understanding The Practicality Of Hardness Tests In Materials Production Processes

Hardness Tests

You may have heard of hardness tests in quality control processes. Hardness tests can tell quality control officers a lot about a product. It offers insights into the flexibility, strength as well as the durability of a product. Hardness tests are performed on all types of products including raw materials and finished products. Hardness testing is easy to perform and is usually non-destructive. The test does not require major alteration to the product and advancements in technology mean that modern instruments give highly accurate readings.

How Hardness Testing Has Changed

In previous years, scratch tests were conducted to determine the hardness of a part. The testing was based on an object that had increasing hardness from one point to another. Testing was done by having the part being tested scratch various points of the bar. The level at which the part could produce a scratch on the object determined its hardness. As industries progressed, quality control officers began to use diamonds and even steel balls to determine how hard an object was. Regardless of which method, these approaches were slow and were not suited for the high-pressure demands of modern industries. For this reason, more refined instruments were developed to measure the hardness of a product.

Modern Methods of Hardness Testing

There are a variety of hardness testing approaches today. Some of these include the Rockwell Method as well as the Knoop approach. Rockwell works best with metals and alloys and is favored for the quick results that it produces. On the other hand, the Knoop approach works best for thin materials and coatings. Some hardness measuring instruments can give results very quickly and are highly portable. Modern hardness instruments leave an indentation that is so tiny that it is almost unnoticeable or does not affect the functionality of the product. For instruments that leave a much larger indentation, the indentation mark can always be sanded out so that it is not noticeable at all.

How Hardness Tests are Done

Various tests use different approaches to measure hardness. For example, the Rockwell hardness test process relies on making a small indent on the part being measured by applying a relatively small load on the indenter. This helps to establish the zero-datum position. Once this is done, a bigger indentation is made using a larger load. The difference between the first indentation (depth) and the second helps to establish the required reading. Typically, the process makes use of a diamond cone for testing metals and tungsten is used to test softer materials.

Importance of Hardness Testing

Tests done on the hardness of a material helps to determine the structural integrity of a product. This, in turn, helps manufacturers know whether the product will perform as expected in the market. We can thus say that hardness tests help consumers to use products safely and for long by helping eliminate those that are structurally unsound.

For the best in precision instruments, get in touch with Willrich Precision. We have over 45 years of experience in delivering hardness testers to customers all over the United States.

In The Limelight: Ra Measurements

Ra measurements

Ra is a unit of measurement that is used to express the average roughness of a surface finish. Ra measurement is especially useful because it shows the average deviation that a surface has in comparison to a mean line. However, Ra works great for general applications but faces some limitations when it comes to very specific measurements.

It also might be inadequate for machinists and quality control experts who deal with sensitive equipment. This is because any slight deviation on the surface finish can affect the performance of a part in a significant way.

Understanding How Ra Measurement Works

One of the things a machinist must understand is the relationship between the average roughness and the surface finish in general. Surfaces with varying profiles can still have a similar Ra value but the different profiles mean that these parts work differently.

For example, if a part has scratches on its surface, there is a risk that is might fracture prematurely. This calls upon machinist to ensure that they consider the surface features relative to the functionality of the part.

A More Efficient Approach to Ra Measurement

Sometimes, machinists and quality control officers recommend very tight Ra parameters in order to try and guard against scratches and peaks. This leads to a lot of wastage and is not a very efficient way of dealing with such issues.

Engineers who understand the relationship between Ra values and the surface finishes know that it is easier to clear off the peaks rather than try to use high-tolerance Ra specifications. This approach allows them to achieve the same results but in a far more economical and competitive way.

While this may sound abstract, the ability to do this makes all the difference when it comes to competitive bidding. This is because the former is able to present more competitive bids while achieving the same exact quality specifications.

Getting the Right Average Roughness

When you are machining a part, it is critical to remember that different machining processes produce different kinds of tool patterns. A good example is the roughness that comes from grinding. This is generally of a shorter wavelength as compared to turning. When a part surface undergoes milling, there are even longer wavelength patterns. Sing point boring generally produces the longest wavelength patterns.

Keep in mind that the wavelength we are talking about is the spacing between individual toolmarks and not how wavy the surface of the part is. When taking the Ra measurement values of a surface, care must be taken to ensure that the measurement is not affected by the waviness. This is done by making sure that the cut off length is short enough. At the same time, it must not be too short otherwise only a part of the tool mark is measured. Ideally, use a cutoff length that can include five complete sets of toolmarks.

Need An Excellent Mobile Roughness Tester? Try MarSurf PS 10!

With many manufacturing processes, there is always an emphasis on the quality of a product or part surface. For some products or parts, the surface finish determines how well the part functions. For example, too much roughness on a surface might weaken a part by making it more likely to crack and fail. This is especially true for parts that are subject to contact and thus friction.

Measuring Surface Roughness

The need for accurate measurements when it comes to surface roughness means that that quality control must have the right tools for the job. Not only must these products be very accurate but they must also be able to give quick results. This is because in a production setting, delays in the production line can mean loss of revenue for the organization. Sometimes the parts being measures are too heavy so they can’t be moved to the quality control room. In such cases, it becomes critical to be able to have the measurement instrument on the production floor. This reduces the time spent checking parts and thus saves the business money.

Introducing the MarSurf PS 10

The MarSurf PS 10 mobile roughness tester is one of the best in this category. The MarSurf PS 10 features state-of-the-art features such as a smartphone display that allows for easy use. The roughness tester also has internal memory for data storage but also the capacity to connect to a computer for the transfer of data. Its rechargeable data source allows for around 500 measurements and which increases its mobility. Its small size makes it very portable and very handy in a factory environment.

Other Features of the MarSurf PS 10

            •           Features a clear and adjustable display

            •           Data can be stored as TXT, CSV, X3P or PDF

            •           PDF documents can be created in the instrument

            •           Can undertake 1200 and above measurements between recharge

            •           Features a detachable drive unite

            •           Features the same number of functionalities as laboratory equipment.

            •           Has a favorites function that allows you quick access to commonly used functions

            •           Easy to use thanks to the automatic cutoff selection feature

Things You Need To Know Before Choosing An Ultrasonic Thickness Gage

ultrasonic thickness gage

Before you choose your ultrasonic thickness gage, you have to consider a number of factors. Some of the obvious factors include your budget constraints and also the reason you are buying it for. However, if this is your first-time purchasing equipment like this, then you might not be familiar with some of the other factors which might not be as obvious. It is important to note that these factors might be equally worth considering when choosing an ultrasonic thickness gage from such a competitive market. Furthermore, there are many factors that you need to consider when talking about the application of the instrument.

Before choosing the one that you want to get, you should find out exactly what you can and cannot do. Here at Willrich Precision Instrument, we provide a wide range of metrological products for any of your industrial needs.

Ultrasonic Thickness Gages Explained

Ultrasonic testing to measure thickness is becoming a very popular method. The main reason for using this device is that it can test the thickness of a wall without any form of destruction. It is usually used for the detection of thinning walls as a result of corrosion or as a method used for quality assurance. It can also be used for measuring boilers, aircraft materials, and even pipes.

The market for ultrasonic thickness gages is extremely competitive and there are many different manufacturers. The entry-level handheld units might cost as low as a few hundred dollars and can reach up to thousands of dollars. Usually, the software used for such products are very similar, but manufacturers can alter the internal software to cater to more specific needs. Many companies around the world offer the option to upgrade their products. As a result, a simple thickness gage can be upgraded to a device with datalogging capabilities and live waveform features.

The Material of Your Ultrasonic Thickness Gage

It is essential that you also list out the materials and the range of thickness for each material that you might want to test. Additionally, you should note down the accuracy that you want to achieve, the temperature when you are taking the readings, and the finish of the materials. In the case where a fluid can be applied to it, the fluid is most likely soluble in water and suitable for use with high frequency sound waves.

Considering the Weight and Size

When contemplating which model to purchase, some factors that you should consider include the weight and size of the ultrasonic thickness gage. Firstly, you must check if you have sufficient storage space for the size that you are looking for. Some ultrasonic thickness gages are compact and portable. They can even fit inside your pocket because they utilize AA size alkaline batteries that everyone knows are extremely portable.

On the other end of the spectrum, there are much larger gages because of the battery that they use. For example, if you need long-lasting battery life that uses latest lithium ion technology, then chances are your unit will be much larger. Additionally, you should consider how easy it is to service the unit that you want to buy, bearing in mind the place of manufacture and their reputation in this industry.

The Four Main Types Of Coordinate Measuring Machines

coordinate measuring machines

If you have no prior knowledge about coordinate measuring machines, then this article is for you. In the current market, there are four main types of coordinate measuring machines. These include the bridge, cantilever, gantry and horizontal arm coordinate measuring machines. They all have their own advantages depending on the components that you want to measure. Here at Willrich Precision Instrument, we understand that buying a coordinate measuring machine might not be as simple as you think. There are many types and factors to consider. However, we provide a wide variety of precision instruments for any of your industrial needs.

Bridge Coordinate Measuring Machines

Bridge machines have become increasingly popular over the years. This type of measuring machine allows for probe movement along 3 different axes, X,Y and Z. The unique thing about this machine is that each axis contains a sensor that can judge the position of the probe on any particular axis. It is capable of doing this with micro-meter precision. The bridge machine produces something called a “point cloud” which is done by sampling the three sensors and measuring a particular point on the object.

They have a very simple structure and is easy to use. Bridge machines are also cheap to manufacture and can withstand the test of time by maintaining accuracy consistently. Usually, bridge machines are fixed on a precision granite plate and have two legs to support the carriage. It is interesting to note that a typical bridge machine is only driven on a single side while the other sides are allowed to float freely. Close to 95% of them utilize air bearings so that there is greater ease of movement.

Cantilever Coordinate Measuring Machines

The cantilever coordinate measuring machines are typically used to measure smaller parts. In comparison to the bridge machines, they grant access to the user on three different sides. They also only allow for probe movement on X and Y, creating limitations on the size of the X beam. The rigidity of the machine makes it only suitable for measuring smaller parts. This type of machine will work well in a shop-floor setting because it has automatic loading and unloading capabilities as well.

Gantry Coordinate Measuring Machines

This type of machine is made specifically for measuring parts that are larger in size and heavy in weight but require the precision of a bridge coordinate measuring machine. Typically, gantry machines work best mounted to the floor. Thus, it is important that you provide it with a solid foundation. The smaller machines utilize four upright columns that support the Y-axis beams. On the other hand, larger gantry machines have 6 to 8 columns in relation to the length of the Y-axis.

Horizontal Coordinate Measuring Machines

The horizontal arm machine was first manufactured in Germany and were originally used as scribing tools. The first models were operated manually and were much harder to use as compared to today. The horizontal arm machine is different from the other three types in the sense that is has 2 axes mounted on a saddle that moves up and down the horizontal axis.

Understanding The Role Of Force Measurement In Linear Drives

force measurement

Force is defined as an interaction that has the ability to change the direction of an object. This, however, is only on the condition that the process is unopposed. Force is capable of making any object with mass to alter its velocity and this also includes objects that were initially at rest. Force takes many forms but is inherently either pull or push action applied onto an object. Force tends to have magnitude (how much of the force is being applied on the object) and it also has direction. For this reason, force always has a vector unit. When looking at force, there are certain concepts that one needs to understand.

Key Terms to Understand

There are a number of concepts that are common when talking about force. Thrust refers to the process of increasing the velocity of an object. There is also drag which counters the effect of thrust and decreases the velocity of an object. Another common term that is used when discussing force is known as torque which affects the rotational speed of the object in question. Another term that is common in this field is static. This refers to the description of objects that are at rest. In such cases, there is zero force acting on the object. Static can also happen when there are two opposing forces of equal magnitude acting on the object.

How is Force Measured?

There are various technologies that are used to measure force. These include Thin-film technology where a sputter process is utilized to achieve an atomic bond between the measuring bridge and the measuring cell body. This process is very ideal for measuring force in highly automated processes. Another common approach is to use a strain gauge where a resistance meander is attached to a strip of foil and this is then attached to the point where force is being applied.

Linear Drives

Linear drives are systems that cause translational movement. Because machine elements accelerate in a straight line, it’s logical to have force measurement in those drives as transformational change is taking place. Drive elements have traditionally been driven by hydraulics or are pneumatically powered. This is increasingly changing, and these kinds of drives are being replaced by electric motors, mechanical thrust units or a combination of both. Although these modern systems work through modular systems, they can be adapted to specifically match the needs of the user. The modern systems also have a greater degree of versatility. The only drawback of these systems is that you can no longer measure the pressure of the system.

Advantages of Force Measurements

Force measurement can be done with any linear drive. When you are looking to make precise force measurements, you can place the force transducer anywhere within the system. This will not affect the accuracy of the measurements that you take. Whether you place the force transducer on the actuator, the motor or the precise point where the force is being applied, you are still likely to get the right results.

Understanding Ra Values for Product Development

Ra values

Surface roughness is also known as Ra, but not many people understand what Ra values implies, how it is measured, and why it is critical to product design. Here is what you need to know about Ra values.

Understanding Ra Values

If you take a sample of a part and measure the high and low points of its length, Ra is the mean or average height that lies above or below the line of reference. The higher the Ra number, the rougher a surface is. If Ra is 0, the graph will show a horizontal line, which means the surface is flat. This is impossible.

Other measurement systems operate on the same principle but are not precisely similar. This can cause errors and confusion, so it is essential to know which method you are referring to and to ensure it is identical to that of your part manufacturer. Always ask if you are not sure as conversion charts are available for system-to-system translation if required.

How the Ra Value Concerns You

The Rvalue is the industry standard for giving instructions to a manufacturer on what the roughness level should and should not be for you. This is used for tooling, machined parts and prototypes. It also affects the part’s appearance, functionality as well as its performance.

Ra shows the average mean deviation or the highest high or low, calculated over the sample’s length. There are many ways to achieve the same mean by using various manufacturing processes. All of which will leave a distinctive pattern on the surface. Manufacturers utilize gages to measure and make comparisons on how different machining methods produce differing types of textures.

The patterns on the gauge surfaces differ in the groove spacing, also known as waves. It is one of the factors that determine surface texture. The waves found on the left are of a low frequency, and the frequency increases from left to right. The R, average height, may be similar but the appearance is not.

How Surface Texture is Measured

Surface texture can be measured with different methods, depending on the part geometry, material type, and part feature. A common technique is to use a stylus or probe, also called a surfometer. It is slowly drawn over the part’s face or feature. Any deviation from a reference line is recorded as a gap to be interpreted later.

The Ra value is calculated with ease via such a reading. It may be more desirable to look at the surface area from a broader view to check for more defects on the surface. This can be done via optical photometry.

One primary utilization of optical photometry to identify asperities. These may be scratches, contaminants in the raw material or voids. Mathematically obtained models tend to consider these irregularities as non-important, but for essential applications in defense, scientific and aerospace instruments, an anomaly would be disastrous.

It takes a combination of both machine and human intelligence for the right decision on surface texture to be made.

Do You Need Coordinate Measuring Machines Or Vision Systems?

coordinate measuring machines

Oftentimes, you get confused about which measurement system can best be applied in an in-house lab. The answer is usually either a Vision System or a Coordinate Measuring Machine (CMM). The CMM style probing has grown in popularity in use for vision systems. This makes choosing which system to apply in your business less straightforward. The following post aims to explain some important factors that need to be considered in order to make your decision of which measuring equipment to use simpler. Some of the important factors to consider when deciding on coordinate measuring machines or vision systems include:


Always have the size of your smallest feature in mind when choosing an inspection system. Vision systems are more accurate when dealing with smaller features of about 3-5mm. As for larger features, you need not worry about them since both coordinate measuring machines and Vision Systems can be used to handle them.


One of the key considerations to keep in mind when choosing a measuring system is the nature of the characteristics to be measured. You can equip your Vision systems with full probing, to make it a CMM for rapid coordinate metrology. By integrating the CMM with the Vision systems, a high speed, highly automated, 3D coordinate acquisition system can be developed. Its potential applications can be used in a broad spectrum of manufacturing problems with a big impact on inspection and metrology. 


Vision Systems are less dependent on probe approach speeds and moving probes. This gives them the potential to move faster, 5-10 times faster than other measurement systems. 


For the longest time, Vision systems have been used in 2D measurements. The ability to use CMM and vision probing on the same machine as well as interchangeably makes Vision systems the go-to measurement system in most 2½-Dand 3D applications. Vision systems and the part 2D in nature, are the preferred choice of measurement system in the event that the main datums are visible on one view of your print. 

From the above, it is safe to say that choosing which measurement system to use is not as black and white as some would think. A lot of key factors need to be put into consideration when deciding on which system to go for. 

At Willrich Precision Instrument, our staff is ready to guide you in determining which system best suits your needs. We are ISO certified and have been in business for over 40 years, offering solutions pertaining to gaging, inspection and metrology. We work diligently to maintain customer satisfaction by providing expert assistance through our knowledgeable staff. 

If you would like to discover more about our products and the services we offer, feel free to contact us today. 

What You Need To Know About Thread Inspection

thread inspection

Thread inspection is described as a ridge of uniform sections in the form of a helix on the external or internal cylinder surface. External threads are found on studs, screws, or bolts, while internal threads are located on tapped holes and nuts.

A large number of machine parts that are fastened to each other are attached via threading. Accurately produced threads are critical for each thread to bear the load evenly. If the male or female threads have a manufacturing flaw, the load distribution will be uneven, meaning some threads will bear more weight than they should. This can be quite disastrous, thus the importance of thread inspection.

Thread Inspection Basics

If you join two parts via threading, the two types of threads are male and female, with the male screwing into the female. As mentioned above, the two types of threads are internal and external. In a nut and bolt example, the bolt is the male and the nut is the female. The nut has threads on the inside, meaning it is an internal thread, and the bolt has threads on the outside, which makes it an external thread.

For the nut and bolt to fit each other, they have to be machined to the same size. The external thread diameter must match the internal thread’s smallest diameter, the pitch of the thread must match, the thread quantity per given length must match, and much more. 

The geometrical measurements needed to inspect a threaded component would be very labor and time-intensive and thus impractical. The solution to this is thread gaging.

Thread Gaging

Thread gaging is the process of inspecting threads, and there are two types of thread gauging:

  • Thread Plugs: Thread pugs are plugs that have external threading, and they are used to measure internally threaded parts such as nuts.
  • Thread Rings: Thread rings are the opposite of thread plugs. They are rings with internal threads and are used for measuring externally threaded parts such as bolts.

Thread plugs and rings are made from old gage steel, which is exceptionally resistant to wear.

Basics of Thread Gaging 

All threads are considered as attribute gages, which mean they do not give any feedback on the exact dimensions. This differs from the measurements you would get from a caliper, which provides you with the precise measurements of whatever you are measuring. 

Thread gages have what we call a Go/No-Go measurement. A threaded plug best explains an example of this measurement. For inspection of the internal thread, the ends of the plug are inserted into the threaded part. The plug’s Go-end should thread in, while the No-Go end should not. If the Go/No-Go test works, the component passes the inspection. If the Go-end part does not fit, then the threaded portion is too small, and vice versa. If the No-Go end fits, then the threaded part is too large.

A thread ring works based on the reversed version of a similar principle. The rings come in a set, and the Go ring is machined to a size smaller than the nominal while the No-Go ring is manufactured to be a little bigger than the nominal. In short, the Go ring is supposed to thread into the machined part while the No-Go ring is not supposed to do so. The Go/No-Go method of measurement is swift and very accurate.

Understand The Three Rs Of Sensor-Based Mechanical Measurements

Sensor-Based Mechanical Measurements

When you are dealing with sensor-based mechanical measurements, there are three important Rs that you should be aware of. These are Resolution, Response, and Repeatability. Understanding how these apply to your sensor-based mechanical measurements will ensure consistent and accurate results from instruments designed to take sensor-based mechanical measurements.


refers to the measure of variability in the results of a sensor-based measuring
system. Repeatability applies for a number of trials of an identical object in
an unchanging environment. Typically, quality control engineers will run about
three to five trials in order to establish repeatability. In a machining
process, this parameter is usually established by taking the average of the
variations in outputs across the various trials that have been done. It is
often expressed as a percentage of total output although some production
processes express repeatability as an absolute term.

thing to note when working with this parameter is that the tests must be done
exactly the same way for it to be effective.


is the second R and it measures the least variation in the input to a
sensor-based measuring system to produce a measurable change. This parameter is
affected by, among other things, the signal-to-noise ratio of the analog
output. This noise often masks changes in the system’s output and the machinist
should be aware of this variable. When expressing resolution, many quality
control systems express it as a percentage of the total output but some express
it in absolute terms.


parameter looks at the sensor-based measuring system’s operation while under
rapidly changing conditions. This parameter is not just a sensor specification
but is a measuring system parameter. Response is characterized in several ways
such as bode plots and phase lags. The purpose of this parameter is to look at
how well a measuring system can hold up to changing inputs before the readings
become unstable.

It is
important to note that all these three parameters are interconnected and affect
each other. For example, repeatability can be affected if the resolution is
inadequate and so on. Machine operators must always be aware of system-level
interactions that affect the overall accuracy of these measurement units. The
other thing to remember is that machining environments rarely offer the
constant environment that these sensor specifications are designed for. There
will likely be variations in temperature, humidity and much more. Being aware
of all these factors allows a machine operator to correctly calculate and
translate these readings.

At Willrich Precision
we do more than just sell high-quality instruments. Over the last four decades
that we have been in operation, we have built partnerships with our partners
that are mutually beneficial. Our clients can count on us for that personal
touch that our physical presence brings. That notwithstanding, we also have an
online presence for speed and convenience. By being both online and having a
‘brick and mortar’ presence means that our clients can always get personalized
service if they wish. They can also enjoy the speed and convenience of shopping
online from our store.