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Precision Gages

5 Thread Gage Details for Your Facility

Working with metals often includes a variety of materials. Focusing on welds, metal panels and parts could take attention away from the actual "nuts and bolts" used in projects as well. These pieces, along with screws, must fit well together and thread gages often make that possible. Measuring "threads" of screws and nuts ensures solid fitting, and gages are the tools you'll need. What gage details are needed to use them? 1. Using Appropriate Type If you never knew that "gage" was the name for the tool you've been using, you may also not understand that all kinds of different ones exist. Basic plug gages measure pitch diameter, but if you need information about how many times a screw will be turning every inch, a measurement called TPI, you have to engage a ring gage. Recognizing which gage is most appropriate will save time and get work accomplished faster. 2. Checking Gages Gages, like most instruments, will wear down over time and be less effective than when they were new. For this reason, testing with master plugs should reveal how effective your gages are on any given day. If you realize they're too old to do their work properly, consider new pieces.  3. Protecting Against Rust Gages, like the equipment they measure, are created from metals or metal alloys. As such, corrosion and rust aren't impossible. This is something you'll need to regularly protect against. Watch facility conditions and keep airflow venting well. Ensure that you purchase gages with anti-corrosion properties or that you keep them clean and dry. Oil-based waxes should help too. 4. Keeping Multiple Gages Whether your gages aren't calibrated properly or are in use by multiple workers at once, keeping multiple gages in workstations and on-site is wise. Estimate need, seek feedback about the types most needed, and buy accordingly. 5. Holding Training Sessions You may have hired employees based on their abilities with industrial machinery and equipment, but it's possible that their methods have become sloppy or that their memories of the proper technique are rusty. Therefore, it's beneficial to employ training sessions for both new and existing workers. Correct thread gage usage and test accuracy so that when they're using the equipment in their tasks, you can trust their work. Thread gage experts, retailers, and your own employees can provide more input about how to best work with these pieces in your business. Utilize these suggestions; gage work should be simple and effective for all. For more information, contact a company like WESTport.

Tips for Maintaining Industrial Thread Gages

Thread gages are important tools that are used in industrial settings to measure screw threads and calibrate gages properly. When your company invests in thread gages, it is natural to want them to last for as long as possible. While thread gages do not require a lot of maintenance, there are several things that should be done to keep them in good condition to ensure that they last a long time and can take accurate measurements and make the right calibrations. If you're ordering new thread gages, use the following tips to take care of them. Keep the Thread Gages Clean Keeping your company's thread gages clean can help extend their lifespan and ensure that they work properly as needed. Thread gages should never have extended contact with dirt and oil, as they can corrode the surface of the thread gage. This includes the oils on the skin, so make sure that anyone who uses a thread gage washes his or her hands beforehand. After calibration, the thread gage should be cleaned with a quality solvent that removes oil and dirt and then carefully wiped dry. Store in a Dry, Cool Area Since thread gages are used to make precise measurements, it is important that there are no changes to its size. Thus, it is important to keep thread gages stored in a cool, dry area where they will not be exposed to heat or sunlight since these things can cause the metal of the thread gage to expand and then contract when it cools down. It is best to store thread gages on a clean piece of cloth in a container and then place the container in a cool spot. Train Inspectors and Operators in How to Use and Care For Thread Gages When new thread gages are purchased for your company, it is a good idea to offer a refresher course in using and maintaining thread gages, so all inspectors and operators understand what to do. Proper training can help ensure that no thread gages are ruined due to improper use or not keeping the gages in the right condition. Keep Thread Gages Properly Labeled Since thread gages are available in different sizes, it is very important that each one is clearly labeled. If a thread gage is not labeled, it can be used for the wrong inspection or calibration, which can lead to the thread gage being damaged in the process. For more information, contact a company like WESTport.

Optimizing Product Lines: How to Guarantee Your Company’s Goods are Superior in Quality

A manufacturing company prospers or fails based on the quality of the products manufactured. Because quality is so important to the success of the company, procedures must be put in place to make sure the products properly meet the customer’s needs, not only the first time but every time. Create a Plan Before the first item rolls off the assembly line, management must create a plan of action. This plan of action addresses many factors, such as calculating how much manpower is needed to complete the order, ensuring enough raw materials are on hand to complete the order, and understanding what quality control measures must be put into place to make sure that each item produced exactly matches specifications. Maintenance The company must maintain three key factors to ensure the quality of a company’s goods remains superior to that of the competition. The equipment on the production line must be regularly maintained. Not only does regular maintenance prevent unscheduled outages, it assures the equipment will continue to produce consistently accurate products. When staff turnover leads to hiring new employees, those new employees must be just as qualified as the persons who left. Equally important to hiring qualified personnel is maintaining an active training program, especially when equipment upgrades occur and when replacing displaced workers. Lastly, the finished product is only as good as the raw materials that go into it. Purchase those products from a reliable vendor and regularly inspect purchases for consistent purity. Quality Assurance Whether a company makes cupcakes or bolts, not all quality assurance can be assessed by sight. Fortunately, you can find companies like WESTport Corporation that specialize in the development, production, and distribution of quality assurance devices. These companies provide the tools needed to assess to the nth degree just how accurate company’s goods meet specifications. Unfortunately, not all quality assurance companies are equally trustworthy. That is where word of mouth and reputation can aid in separating the winners from the losers. Commitment Superior goods come from a commitment to excellence. From the president down, instill the need for accurate calibrations, reduced defective products, and increased pride in a job well done. To guarantee your company’s goods are superior in quality, create a viable plan of action that details the who, what, when, and how of production. Follow up the plan with consistent maintenance and a reliable quality assurance routine and watch your defects numbers decrease while your customer satisfaction ratings skyrocket.

Med Tech: How Modern Technology is Impacting Patient Care

Posted on March 6, 2018 Technology has played a significant role in improving the quality of care for those in hospitals, nursing homes, or even the patient’s own home. Still, much of the public is unaware or skeptical of technology’s role in nursing and patient care. Here we’ll discuss some of the great strides made in technology regarding the medical field. Gauges Companies such as WESTport lead the way in the design and manufacturing of variable and fixed limit gauges for the use throughout the medical industry. Some of the common applications of these gauges are for bone support plates, bone screws, conical threads, etc. They are meant to help doctors with orthopedic and prosthetic devices. Restoring Vision Nano-Retina has created a duel-system treatment for the blind, with a chip being implanted to the eyeball coupled with sophisticated eyeglasses to restore several vision qualities using electromagnetic cells that work like photoreceptors. For disinfection efforts, new technologies like UV light bulbs and portable UV robots can be held in hospital rooms to create chemical reactions using oxygen in bacterial cells, causing them to die, the same way bleach would kill them. Emergency Treatment Electronic cameras placed in ambulances can now allow doctors to communicate with paramedics before even arriving to the hospital. Paramedics can administer medicine and physical treatment to patients in emergencies where time is often the essence of life or death. These are just a few of the physical devices that are in use today. Services & Remote Patient Care The revolution of technology and healthcare hasn’t stopped at the hospital, as the digital age has helped patients become more independent and safer within their own homes, along with services that help reduce the confusion regarding their next step. Need a second opinion? Online services like Grand Rounds and 2nd MD allow you to talk to doctors and get advice easy and quick for those instances where you’re just not sure. Analytic specialists like Metalogix and Lumiata help record patient information to help nurses monitor patients remotely through technology that allows them to track patterns in patients and their habits without having to be physically present. Other services like ZocDoc and Rightcare can help you schedule appointments and guide you through readmission processes. Even with everything discussed, there are still thousands of advancements available to help patients that much of the public isn’t aware of. It is important to be in the loop of technology, because not only has it provided us many luxuries, but it has also saved thousands of lives. by Lizzie Weakley

Gage Care Tips

How Should I Care for My Gages? Clean the part before gaging by removing any dirt, coolant or chips NEVER force the gage. Always use light pressure. Protect the gage from damage. Nicks and burrs cause inaccurate results. Keep gages clean and coated with a thin coat of rust preventative and stored properly. This will increase the wear life of your gage(s). Avoid handling gaging surfaces. The oil from your fingerprints causes rust. Gages should be protected from exposure to excessive heat, moisture and corrosive chemicals. The temperature of the gage and the part should be the same to avoid any effects of thermal expansion on the material. The best temperature for the part and the gage to be inspected at is 68° degrees Fahrenheit. Gages should be periodically calibrated to insure accuracy. Gages and "Go" gages in particular, will wear with normal use and require recalibration. Frequency of calibration is dependent on such factors as how often the gage is used, part abrasiveness, tolerance, and applicable quality procedures. All gages should be monitored and maintained accordingly to insure accuracy. Got Any Other Tips for Me? Quality Gaging Tips – Where’s the fault?

Types of Mechanical Gauges

Ruler and scales: They are used to measure lengths and other geometrical parameters. They can be single steel plate or flexible tape type tool. Calipers: They are normally of two types- inside and outside caliper. They are used to measure internal and external size (for e.g. diameter) of an object. It requires external scale to compare the measured value. Some calipers are provided with measuring scale. Other types are odd leg and divider caliper. Vernier caliper: It is a precision tool used to measure a small distance with high accuracy. It has got two different jaws to measure outside and inside dimension of  an object.It can be a scale, dial or digital type vernire caliper. Micrometer: It is a fine precision tool which is used to measure small distances and is more accurate than the vernire caliper. Another type is a large micrometer caliper which is used to measure large outside diameter or distance. Feeler gauge: Feelers gauges are a bunch of fine thickened steel strips with marked thickness which are used to measure gap width or clearance between surface and bearings. Telescopic feeler gauge: It is also known as tongue gauge and it consists of long feeler gauge inside a cover with tongue or curved edge. The long feeler strips protrude out of the cover so that it can be inserted in to remote places where feeler gauge access is not possible. Poker gauge: This gauge is used to measure propeller stern shaft clearance, also known as propeller wear down. Bridge gauge: Bridge gauges are used to measure the amount of wear of Main engine bearing. Normally the upper bearing keep is removed and clearance is measured with respect to journal. Feeler gauge can be used to complete the process. Liner measurement tool: Liner measurement tool is a set of straight assembled rod with marked length in each set. It is used to measure the wear down or increase in the diameter of the engine liner. American Wire Gauge: American wire gauge or AWG is a standard tool which is circular in shape and has various slots of different diameter in its circumference. It is used to measure cross section of an electric cable or wire. Bore Gauge: A tool to accurately measure size of any hole is known as bore gauge, It can be a scale, dial or digital type instrument. Depth gauge: A depth gauge is used to measure the depth of a slot, hole or any other surface of an object. It can be of scale, dial or digital type. Angle plate or tool: It is a right angle plate or tool used to measure the true right angle of two objects joined together. Flat plate: Flat plate is a precised flat surface used to measure flatness of an object when it is kept over the flat plate. Dial Gauge: Dial gauge is utilized in different tools as stated above and can be separately used to measure the trueness of the circular object, jumping of an object etc. Lead Wire: It is a conventional method to used soft lead wire or lead balls to measure the wear down or clearance between two mating surfaces. The lead wire or balls of fixed dimension is kept between two surfaces and both are tightened against each just as in normal condition. The increase in the width of the lead wire or ball will shoe the clearance or wear down. These are some of the main tools that are used on board ship. If you feel we have missed any important tool, then let us know and we will add it in the list. Snap Gauges: A snap gage is a form of Go/no go gauge . It is a limit gage with permanently or temporarily fixed measurement aperture(s) (gaps) which THREAD PITCH GAUGE   Three different sets of threading gauges: A thread pitch gauge, also known as a screw pitch gauge or pitch gauge, is used to measure the pitch or lead of a screw thread. The uppermost gauge in the image is an ISO metric pitch gauge, the larger gauge in the center is for measuring the Acme thread form, and the lower gauge is for Whitworthscrews. Thread pitch gauges are used as a reference tool in determining the pitch of a thread that is on a screw or in a tapped hole. This tool is not used as a precision measuring instrument. This device allows the user to determine the profile of the given thread and quickly categorize the thread by shape and pitch. This device also saves time, in that it removes the need for the user to measure and calculate the thread pitch of the threaded item.   PROFILE GAUGE A profile gauge or contour gauge is a tool for recording the cross-sectional shape of a surface. Contour gauges consist of a set of steel or plastic pins that are set tightly against one another in a frame which keeps them in the same plane and parallel while allowing them to move independently, perpendicularly to the frame. When pressed against an object, the pins conform to the object. The gauge can then be used to draw the profile or to copy it on to another surface. Applications Profile gauges are used widely in metalworking and woodworking. In architectural conservation, they are used to document the profiles of decorative moldings. In archaeological illustration, they are typically used to record the profile of pots, and are thus named pottery gauges; but in ceramics, a pottery gauge is a template used in making pots.   GAUGE BLOCK   A gauge block (also known as a gage block, Johansson gauge, slip gauge, or Jo block) is a precision ground and lapped length measuring standard. Invented in 1896 by Swedish machinist Carl Edvard Johansson, they are used as a reference for the calibration of measuring equipment used in machine shops, such as micrometers, sine bars, calipers, and dial indicators(when used in an inspection role). Gauge blocks are the main means of length standardization used by industry.   RING GAUGE A ring gauge, or ring gage, is a cylindrical ring of steel whose inside diameter is finished to gauge tolerance and is used for checking the external diameter of a cylindrical object. Ring gauges are used for comparative gauging as well as for checking, calibrating, or setting of gauges or other standards. Individual ring gauges or ring gauge sets are made to variety of tolerance grades in metric and English dimensions for master, setting, or working applications. "Go" spline ring gage There are three main types of ring gauges: go, no go, and master or setting ring gauges. Go ring gauges provide a precision tool for production comparative gauging based on a fixed limit. Go gauges consist of a fixed limit gauge with a gauging limit based on the plus or minus tolerances of the inspected part. A go ring gauge's dimensions are based on the maximum OD tolerance of the round bar or part being gauged. A go plug gauge's dimensions are based on the minimum ID tolerance of the hole or part being gauged. The go plug (ID) gauge should be specified to a plus gauge makers' tolerance from the minimum part tolerance. The go ring (OD) gauge should be specified to a minus gauge makers' tolerance from the maximum part tolerance. No-go or not-go gauges provide a precision tool for production comparative gauging based on a fixed limit. No-go gauges consist of a fixed limit gauge with a gauging limit based on the minimum or maximum tolerances of the inspected part. A no-go ring gauge's dimensions are based on the minimum OD tolerance of the round bar or part being gauged. The no go ring (OD) gauge should be specified to a plus gauge makers' tolerance from the minimum part tolerance. Master and setting ring gauges includes gauge blocks, master or setting discs, and setting rings are types of master gauges used to calibrate or set micrometers, optical comparators, or other gauging systems. Working gauges are used in the shop for dimensional inspection and periodically checked against a master gauge.   TELESCOPIC GAUGE Telescopic gauge set These are a range of gauges that are used to measure a bore's size, by transferring the internal dimension to a remote measuring tool. They are a direct equivalent of inside calipers and require the operator to develop the correct feel to obtain repeatable results. The gauges are locked by twisting the knurled end of the handles, this action is performed to exert a small amount of friction on the telescopic portions of the gauge (the smaller diameter rods found at the T head of the gauge). Once gently locked to a size slightly larger than the bore, the gauges are inserted at an angle to the bore and slowly brought to align themselves radially, across the hole. This action compresses the two anvils where they remain locked at the bores dimension after being withdrawn. The gauge is then removed and measured with the aid of a micrometer or caliper.   SMALL HOLE GAUGES Small hole gauge set. Sizes from top to bottom: 3 to 5 mm (0.118 to 0.197 in) 5 to 7.5 mm (0.197 to 0.295 in) 7.5 to 10 mm (0.295 to 0.394 in) 10 to 13 mm (0.394 to 0.512 in) Small hole gauges require a slightly different technique to the telescopic gauges, the small hole gauge is initially set smaller than the bore to be measured. It is then inserted into the bore and adjusted by rotating the knurled knob at the base, until light pressure is felt when the gauge is slightly moved in the bore. The gauge is then removed and measured with a caliper or micrometer. GO/NO GO GAUGE Hardened and ground plug gauge Replaceable thread and plug gauges   A Go-NoGo gauge (or Go/no go) refers to an inspection tool used to check a workpiece against its allowed tolerances. Its name derives from its use: the gauge has two tests; the check involves the workpiece having to pass one test (Go) and fail the other (No Go). It is an integral part of the quality process that is used in the manufacturing industry to ensure interchangeability of parts between processes, or even between different manufacturers. A Go NoGo gauge is a measuring tool that does not return a size in the conventional sense, but instead returns a state. The state is either acceptable (the part is within tolerance and may be used) or it is unacceptable (and must be rejected). They are well suited for use in the production area of the factory as they require little skill or interpretation to use effectively and have few, if any, moving parts to be damaged in the often hostile production environment.

3 Interesting Tidbits From the History of Fixed Limit Thread Gages

If you have used thread gages for decades in your daily work, you know that these simple objects offer a quick and easy way to test inside major diameter, outside major diameter, and pitch diameter limits on threaded parts. But you may not know the facts about these gages listed below. Read on to discover some cool-to-know tidbits about these valuable tools. 1. What's the Difference Between "Gage" and "Gauge"? Thread gages (and many other types of gages) typically use the g-a-g-e spelling, but for most English speakers and writers, g-a-u-g-e is the more common spelling. Why the discrepancy? According to the Merriam-Webster dictionary, both spellings of gage were widely used in the 1400s. At that time, English spelling had not been standardized by dictionaries and linguists as it has today. People used both "gage" and "gauge" to mean the same thing. (And, of course, when they spoke, spelling didn't matter.) By the late 1800s, "gauge" became the preferred spelling in common usage for the word that means an instrument or standard for measuring. However, the "gage" spelling remains common in more technical fields, such as manufacturing and engineering. Thus, thread gages still use the spelling without the "u"-and likely will for the foreseeable future. 2. When Did Thread Gages First Appear? It's almost impossible to pinpoint a specific date in history when thread gages (and other types of fixed limit gages) were invented. Rather, they came to exist as a logical necessity during the Industrial Revolution. In the USA, the story begins with Eli Whitney, the inventor known for creating the cotton gin. In 1801, he built 10 guns that all used the exact same size and shape of parts. He took them apart and put them back together in front of Congress to demonstrate the practical value of interchangeable parts. In truth, Whitney wasn't the first to show that interchangeable parts could save governments money on guns. A French man named Honore Blanc had performed a similar demonstration a few decades earlier. Also, Whitney's gun were actually handmade, rather than made by machines and tested with gages for conformity to a specific size standard. Still, Whitney's demonstration popularized the idea of creating parts to fit standard sizes. In the ensuing decades, engineers and inventors created methods for building clocks, sewing machines, steam engines, typewriters, guns, cars, and many other products with interchangeable parts. This development allowed goods to be produced faster and cheaper. Thread gages are one method manufacturers use to determine that parts are interchangeable, or, more precisely, manufactured to reliable and exacting standards. Thread gages test whether internal or external threads meet the requirements for a specific part that serves a specialized purpose. 3. What Makes Thread Gages So Important Today? Today's thread gages can test threaded parts to within very precise accuracy limits. For many industries, these parts must meet those exacting standards so the machines that use them can operate safely. For example, many car components are held together with nuts, screws, and bolts, as are airplanes. Those vehicles transport people and goods over long distances. If the individual parts of those vehicles don't meet exact standards, they may not operate correctly or even arrive at their destinations. Manufacturers use thread gages (and other fixed limit gages) to test various parts to ensure they make reliable, safe vehicles. Of course, thread gages have advantages beyond their ability to prevent crashes and machine malfunction. They also offer upfront cost-saving benefits to the manufacturer for the following reasons: Thread gages are portable, so you can move them from place to place easily for testing purposes. Thread gages are certified to meet industry standards. Thread gages cost less per tested piece than any other testing method. Thread gages are made from wear-resistant materials like carbide, steel, and chrome, so they will last and not require replacement very often. If you need high-quality thread gages, talk to our team at WESTport Corp. We serve clients worldwide who rely on precision measuring instruments.

Hand Taps and Proper Threading Techniques

Whether you’re repairing a damaged thread or threading virgin material, there are a number of factors to consider and procedures to follow to produce the best job, with the least amount of wear and tear —and breakage, on your tooling. Threading is divided into two types, internal and external. Internal threading is done by using a tool called a TAP in a hole drilled to a specific diameter for the thread size and pitch you want to cut. External threads, such as for bolts and studs, are made by using a tool called a DIE, which is applied to a specific diameter of rod for the size and pitch of the threads you want to cut. Both taps and dies can be used to either cut new threads or repair damaged threads. Taps and dies come in various configurations and materials, the most common being High Speed Steel (HSS) for softer materials and Cobalt for hard materials like stainless steel. Some manufacturers apply platings or coatings designed to increase the cutting ability and life of their products, beneath that, it is usually one of the two materials for most applications. The threads found on most mass produced externally threaded products such as bolts, studs and screws, are formed by a process known as thread rolling. A headed, but unthreaded blank is squeezed between two opposing dies, much the same way you would roll a twig between the palms of your hands. This rolling action displaces the  metal of the blank, forming threads. Machine produced threads are what is referred to as a Class 2A fit and has considerable variation in tolerance compared to a cut thread. Threads produced using taps and dies, whether by hand or machine, are what is referred to as cut threads. Cut threads are generally of better quality and closer tolerance which is why a die nut run on the threads of a brand new fastener might still remove some material, and/or plating. Hand Tapping Hand taps come in three basic configurations -Taper, Plug and Bottoming. TAPER taps have the first 7 – 10 threads at the tip ground flatter than the main body of the tap to enable easy starting of the threads in the hole. Sometimes called a starter tap, taper taps can be be used to start the thread in a blind hole for another tap to finish or used to cut threads all the way on a through hole. PLUG taps are like taper taps in that they have tapered threads at the starting end of the tap,  the difference is there are fewer of them, usually the first 3-5 threads, so you get to cutting a full thread sooner. Although not as easy to start as a taper tap, they can be used to start a thread. If you can only buy one type of tap, and you’re a patient user, plug taps can be a good choice because they are still easy to start, but they can also form complete threads deeper into a blind hole than a taper tap.   BOTTOMING taps have no ground threads at the starting end and are generally used after, and in conjunction with a taper or plug tap. Bottom taps can cut threads to the bottom of blind holes although they do not do well at starting threads.   Threading Dies Hand threading dies are generally of two types. ROUND dies are designed to fit in a T-handle while HEX DIE NUTS can be used with regular hand tools. (Wrenches and sockets.) Round dies are usually the choice for cutting new threads whereas hex die nuts are commonly used as a chaser to repair existing threads. Round dies also require a holder/handle to use them, whereas hex die nuts do not. Proper Hand Thread Cutting Techniques Taps Are Brittle – Handle With Care In order for taps and dies to cut, they must be harder than the materials they are cutting.  This additional hardness also makes them brittle, meaning, they can be easily broken, something you want to avoid at all costs. It is always preferable to use a proper T-handle for taps rather than a wrench or locking pliers. The latter two work, in a pinch, but you must be careful because turning the tap from one side only can put asymmetrical stress on the tap, causing it to go off center, or break. Using a T-Handle keeps the force applied over the center of the tap or die, maintaining proper symmetry. Lubricate! Although there is really not much heat build-up to speak of when had cutting threads, lubricating the cutting threads can reduce friction binding and aid in chip removal. You can use a a specialty tapping fluid, a light machine oil, a little WD-40, even a shot of PAM will work. In a pinch, you can even use saliva. You don’t need a lot of lubrication, a little sliptivity goes a long way and will make the job easier. Take Your Time You really don’t want to mess up a tapping job. Breaking a tap off in a hole —especially below the surface level will cause you untold frustration and possibly a number of colourful expletives! Remember, taps are very hard, so trying to drill one out can be difficult, if not extremely messy. Take your time, go slow, this is truly one of those situations where haste could indeed make waste —of several hours of your time and possibly, your wallet. Break Up The Chips The cutting teeth on a tap are not continuous all the way around the tap body. There are usually 3 or four cutting sections separated by a groove, called the flute, between them. Once the first full teeth begin cutting, the metal being removed may be a long strip, called a swarf, or chips. The flutes job is to provide clearance so the chips can be kept clear of the cutting teeth and pushed out the top of the hole. It is extremely important that these cuttings be broken up to prevent jamming and breaking the tap. The best way to do this is to turn the tap in the direction of cutting until you start to feel it bind. At this point, turn the tap slowly in reverse until you hear, or feel a ‘click’ of the chip breaking away from the material being cut. The vast majority of tap breakage can be avoided by making sure you break the chips, and the smaller the tap, the more important it is. Understanding Thread Type And Sizes In North America, and Canada in particular, there are two main thread series in use. The oldest of these uses Imperial fractional measurement and is often referred to as SAE which stands for The Society Of Automotive Engineers. Back in 1916 when the association was formed, the term ‘automotive’ was derived from Greek where ‘auto’ means self and from the latin word ‘motivus’ which means of motion. In other words, any form of self-powered vehicle. As the Society developed it came to incorporate the standards of the various other associations of self-powered vehicles, everything from tractors to aircraft. The SAE standard thread pitches are measured in TPI or threads per inch. For each diameter of SAE threads, there are also two pitches, commonly referred to as UNC or Unified National Coarse (commonly called coarse thread) and UNF or Unified National Fine (fine thread). The other, more recently adopted standard is known generally as metric but actually encompasses a number of different standards, from different countries. DIN, ISO, JIS, these are all metric standards. Metric thread pitches are expressed as the distance between threads, so a thread pitch of 1.0mm would mean it was 1.0mm between the tops of two adjacent threads. For the most part, the various metric standards agree on a dimensional standard and a common coarse thread pitch, which is the most widely used. Fine pitch metric fasteners do exist and often come in more than one fine thread pitch —some as many as 4 or 5! This can cause some confusion and one should really have a thread gauge if they are in doubt. For a better view of the SAE and metric thread available, download a copy of the handy Tap/Drill Chart at the end of this article. Use The Correct Hole Size Also on the Tap/Drill chart you will find the correct size drill bit for the hole you have to drill and it’s decimal equivalent. Using the correct hole size is important on two points. First, if the hole is too large, the root of the threads will be too shallow and insufficient and may strip out or fail. If the hole is too small, it will cause the tap to bind and quite possibly break trying to cut too much material. People are often unaware that there are four different series of standard twist drills. We all know about fractional and metric sizes, but with twist drills there are also Number and Letter drills. Sometimes, the hole size you need is not a standard fractional size. 1/4″-20 for example, requires a #7 drill bit for proper threading. Oh, and coarse and fine threads are always different drill sizes. On some softer materials, like aluminum and thin mild steel, you can use the ‘close enough’ principle, but consider the strength and purpose of the resulting thread. In such cases, it’s always better to use a slightly smaller bit than a slightly larger one. Chip clearing is even more important here and the tap should be well lubricated and extracted during the threading process to keep the hole, threads and tap clean and free of debris and chips. Buy What You Need — Buy Quality Sure, you can buy a complete tap and die set, but do you really need it? Oftentimes it’s better to just buy the taps you need or use on a regular basis, pay a little more, and get a better, more reliable tool. Economical tap and dies sets, while able to fill your current and future needs, might be false economy if the products are poorly made. FREE Tap Drill Chart How often do you get something useful for free? Well, here you go! Please feel free to download a copy of our Tap and Die Chart. It will give you all the threading information you need and includes an SAE-Metric-Decimal equivalent chart. Download Link KMS_Tap_Drill-ShopChartz™ Posted on January 8, 2012 by Gord Field

Useful Resources

Associations AMT Association for Mfg. Technology ISA Int'l Society for Measurement & Control NTMA National Tooling & Machining Association SME Society for Mfg. Engineers SAE Society for Automotive Engineers ANSI National Standards Systems Network NIST National Institute of Standards & Technology Trade Publications Cutting Tool Engineering Modern Machine Shop Quality Tooling & Production Quality Digest

Gage Calibration FAQs

What are gages used for? Fixed limit gages are primarily used to check dimensions and geometries; plug gages check internal and ring gages external dimensions and geometries. They effectively insure that a part being measured is within its designed tolerance limits. Fixed limit gages are highly accurate, economical and easy to use.   What are the principles of Go/NoGo gaging? To use as a "Go/NoGo" functional check, try and fit both the "Go" and "NoGo" gages into or onto a part being measured. The measured part passes if the "Go" gage fits and the "NoGo" doesn't, otherwise the part fails. A "Go/NoGo" check is strictly a pass/fail test. The actual part size is never measured.   What are the types of fixed limit gages? Plug gages are available in two types’ plain cylindrical and thread, and in several popular styles: reversible, Taperlock, and Trilock. The style is usually determined by the size of the gage. Ring gages are also available as plain cylindrical and thread type gages.   What kinds of wear resistance and tolerance are there? Gages are available in tool steel, chrome, and carbide. Chrome and carbide are harder and provide longer life to the gage. A choice of tolerance is also available. Please refer to the Gagemaker's tolerances chart to see which tolerance best suits your needs.   How is gage tolerance calculated? The standard practice for determining gage tolerance is to allow 10% of the product tolerance to be divided between the "Go" and "NoGo" gages. For plug gages, the "Go" is normally a plus tolerance and "NoGo" a minus tolerance. For ring gages the opposite is true; "Go" is normally a minus tolerance and "NoGo" a plus tolerance. Using this practice as a guideline, gage tolerance is always included in the part tolerance and accounts for up to 10%. This means that 10% of good product could potentially fail the inspection but that no bad product would ever pass.   Is it cost effective to outsource my calibration? Click for answer.   Is gage calibration an investment in quality production? Click for answer.  

Straight Pipe Threads Table Chart ANSI

The following table chart defines Straight Pipe Threads for Mechanical Joints, NPSM and NPSL ANSI/ASME B1.20.1, American Pipe Threads Standard. Straight pipe threads are designated NPSC = National Pipe Straight Coupling. Also generically referred to as "IPS Threads" or "Iron Straight Threads". Note that straight pipe threads, unlike tapered pipe thread do not provide any sealing function. Typically, a design that utilizes a straight pipe thread will incorporate a sealing features, like an oring to facilitate fluid sealing. All chart data given in inches Nominal Pipe Size Threads per Inch External Thread Internal Thread Allowance Major Diameter Pitch Diameter Minor Diameter Pitch Diameter Max. aa Min. Max. Min. Min. aa Max. Min. Max. Free-fitting Mechanical Joints for Fixtures—NPSM 1/8 27 0.0011 0.397 0.390 0.3725 0.3689 0.358 0.364 0.3736 0.3783 1/4 18 0.0013 0.526 0.517 0.4903 0.4859 0.468 0.481 0.4916 0.4974 3/8 18 0.0014 0.662 0.653 0.6256 0.6211 0.603 0.612 0.6270 0.6329 1/2 14 0.0015 0.823 0.813 0.7769 0.7718 0.747 0.759 0.7784 0.7851 3/4 14 0.0016 1.034 1.024 0.9873 0.9820 0.958 0.970 0.9889 0.9958 1 11 1/2 0.0017 1.293 1.281 1.2369 1.2311 1.201 1.211 1.2386 1.2462 1 1/4 11 1/2 0.0018 1.638 1.626 1.5816 1.5756 1.546 1.555 1.5834 1.5912 1 1/2 11 1/2 0.0018 1.877 1.865 1.8205 1.8144 1.785 1.794 1.8223 1.8302 2 11 1/2 0.0019 2.351 2.339 2.2944 2.2882 2.259 2.268 2.2963 2.3044 2 1/2 8 0.0022 2.841 2.826 2.7600 2.7526 2.708 2.727 2.7622 2.7720 3 8 0.0023 3.467 3.452 3.3862 3.3786 3.334 3.353 3.3885 3.3984 3 1/2 8 0.0023 3.968 3.953 3.8865 3.8788 3.835 3.848 3.8888 3.8988 4 8 0.0023 4.466 4.451 4.3848 4.3771 4.333 4.346 4.3871 4.3971 5 8 0.0024 5.528 5.513 5.4469 5.4390 5.395 5.408 5.4493 5.4598 6 8 0.0024 6.585 6.570 6.5036 6.4955 6.452 6.464 6.5060 6.5165 Loose-fitting Mechanical Joints for Locknut Connections—NPSL 1/8 27 ... 0.409 ... 0.3840 0.3805 0.362 ... 0.3863 0.3898 1/4 18 ... 0.541 ... 0.5038 0.4986 0.470 ... 0.5073 0.5125 3/8 18 ... 0.678 ... 0.6409 0.6357 0.607 ... 0.6444 0.6496 1/2 14 ... 0.844 ... 0.7963 0.7896 0.753 ... 0.8008 0.8075 3/4 14 ... 1.054 ... 1.0067 1.0000 0.964 ... 1.0112 1.0179 1 11 1/2 ... 1.318 ... 1.2604 1.2523 1.208 ... 1.2658 1.2739 1 1/4 11 1/2 ... 1.663 ... 1.6051 1.5970 1.553 ... 1.6106 1.6187 1 1/2 11 1/2 ... 1.902 ... 1.8441 1.8360 1.792 ... 1.8495 1.8576 2 11 1/2 ... 2.376 ... 2.3180 2.3099 2.265 ... 2.3234 2.3315 2 1/2 8 ... 2.877 ... 2.7934 2.7817 2.718 ... 2.8012 2.8129 3 8 ... 3.503 ... 3.4198 3.4081 3.344 ... 3.4276 3.4393 3 1/2 8 ... 4.003 ... 3.9201 3.9084 3.845 ... 3.9279 3.9396 4 8 ... 4.502 ... 4.4184 4.4067 4.343 ... 4.4262 4.4379 5 8 ... 5.564 ... 5.4805 5.4688 5.405 ... 5.4884 5.5001 6 8 ... 6.620 ... 6.5372 6.5255 6.462 ... 6.5450 6.5567 8 8 ... 8.615 ... 8.5313 8.5196 8.456 ... 8.5391 8.5508 10 8 ... 10.735 ... 10.6522 10.6405 10.577 ... 10.6600 10.6717 12 8 ... 12.732 ... 12.6491 12.6374 12.574 ... 12.6569 12.6686 For ANSI Standard Straight Pipe Thread the major and the minor diameters of the internal thread and the minor diameter of the external thread vary with the pitch diameter. The major diameter of the external thread is usually determined by the diameter of the pipe. These theoretical diameters result from adding the depth of the truncated thread (0.666025 x p) to the maximum pitch diameters, and it should be understood that commercial pipe will not always have these maximum major diameters. Notes for Free-fitting Fixture Threads: The minor diameters of external threads and major diameters of internal threads are those as produced by commercial straight pipe dies and commercial ground straight pipe taps. The major diameter of the external thread has been calculated on the basis of a truncation of 0.10825p, and the minor diameter of the internal thread has been calculated on the basis of a truncation of 0.21651p, to provide no interference at crest and root when product is gaged with gages made in accordance with the Standard. Notes for Loose-fitting Locknut Threads: The locknut thread is established on the basis of retaining the greatest possible amount of metal thickness between the bottom of the thread and the inside of the pipe. In order that a locknut may fit loosely on the externally threaded part, an allowance equal to the "increase in pitch diameter per turn" is provided, with a tolerance of 1 1/2 turns for both external and internal threads.

Fastener Black Book

The FASTENER BLACK BOOK is a Technical Fastener Resource Book consolidating the abundance of Fastener information into a easy-to-read and convenient user friendly format. Whether you are a Designer, Engineer or looking to understand Fasteners better, the Fastener Black Book is an invaluable tool for Apprentices, Trainees, Tradesmen, Machinists, Machine Shops, Tool Rooms, Technical Colleges, Fabricators, Sheet Metal Workers, even simply as a gift to a colleague. Click this link to purchase https://www.amazon.com/Fastener-Black-Book-Reference-Manual/dp/0958057133 Also available in Inch Edition Spiral-bound https://www.amazon.com/Fastener-Black-Book-Inch-Rapp/dp/1921722444

Interpretation of Geometric Dimensioning and Tolerancing 3rd Edition

  Completely updated for ASME Y14.5-2009! Geometric Dimensioning and Tolerancing (GD&T) has become accepted around the world as the international symbolic language that allows engineers and machinists to use engineering drawings to communicate from the design stage through manufacturing and inspection. Deductively organized, this book is a complete on-the-job reference that provides a thorough understanding to the complex ASME Y14.5-2009 "Dimensioning and the Tolerancing" standard. Uses a "building-block" approach with examples (some dimensioned and toleranced in inches and some in millimeters) to illustrate each concept. Reinforces the explanations with end-of-chapter self evaluation exercises (the answers to all questions and problems are contained in the back of the book). Includes over one hundred drawings that illustrate concepts under discussion. Provides the information needed to become conversant in the techniques of GD&T and how to smoothly integrate this knowledge into engineering design and modern inspection systems. Click this link to purchase https://www.amazon.com/Interpretation-Geometric-Dimensioning-Tolerancing-Puncochar/dp/0831134216  

Precision Machining Technology 2nd Edition

  Packed with detailed examples and illustrations, PRECISION MACHINING TECHNOLOGY, 2e delivers the ideal introduction to today's machine tool industry, equipping readers with a solid understanding of fundamental and intermediate machining skills. Now fully integrated with MindTap—an online, highly personalized learning resource—it provides learners with the most interactive and engaging experience available. The text is completely aligned with the National Institute of Metalworking Skills (NIMS) Machining Level I Standard and fully supports the achievement of NIMS credentials. It also carries NIMS' exclusive endorsement and recommendation for use in NIMS-accredited Machining Programs. More comprehensive than ever, the Second Edition includes new coverage of cutting tools, teamwork, leadership, and more. The text continues to provide an emphasis on safety throughout and offers thorough coverage of such topics as the basics of hand tools, job planning, benchwork, layout operations, drill press, milling and grinding processes, and CNC. A companion Workbook/Shop Manual provides helpful review material to ensure readers have mastered key concepts while guided practice operations and projects on a wide range of machine tools will enhance their NIMS credentialing success. Time-saving instructor resources are available at the Instructor Companion Site for the text. The carefully created resources include: PowerPoint chapter presentations with selected images, an Image Library containing images from the book, an Answer Key for both the Textbook and Workbook, and a NIMS Duties and Standards Correlation Grid. Also available with the text is a link to Cengage Learning Testing Powered by Cognero a flexible, online system that allows you to author, edit, and manage test bank content from multiple Cengage Learning solutions; create multiple test versions in an instant deliver tests from your LMS, your classroom or wherever you want. Click this link to purchase https://www.barnesandnoble.com/w/precision-machining-technology-peter-j-hoffman/1119330208

Precision Manufacturing

  Precision Manufacturing provides an introduction to precision engineering for manufacturing. With an emphasis on design and performance of precision machinery for manufacturing – machine tool elements and structure, sources of error, precision machining processes and process models sensors for process monitoring and control, metrology, actuators, and machine design. This book will be of interest to design engineers, quality engineers and manufacturing engineers, academics and those who may or may not have previous experience with precision manufacturing, but want to learn more. Click this link to purchase https://www.amazon.com/Precision-Manufacturing-David-Dornfeld/dp/0387324674

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