Ames Portable hardness testers

Measuring Hardness Rockwell Scale

Hardness Testing in Rockwell Scales

Hardness Testing – Rockwell scales

Rockwell Hardness testing is a system for determining the hardness of metals and alloys of all kinds. The American Society for Testing and Materials (ASTM) has established a standard recognized worldwide to help manufacturers maintain the qualities they want in their products. If you are using the Brinell scale check out our conversion chart.      

ASTM Standards E-18 and E-110 defines the test method and parameters for a valid test using portable hardness testers. Following is a general description of the method. A spheroconical diamond penetrator or a carbide ball penetrator is forced into the surface being tested at a predetermined pressure load. The hardness is read as a function of the depth of penetration.

To overcome errors in measurement, two pressure loads are applied in sequence. The first, a minor load is applied and the readout dial is “zeroed” with the part being tested still under load. Then the major load is applied.  The penetrator is backed out to the minor load point to read the distance traveled. The hardness reading represents the additional depth of penetration beyond the minor load.  Tester accuracy is checked by running the test on specimens whose hardness has been certified by an independent testing laboratory. All Ames hardness testers perform genuine Rockwell Hardness tests, giving a direct Rockwell reading. Their accuracy meets or exceeds ASTM Standards E-18 and E-110. Each tester comes complete with test specimens to assure continued accuracy. 

*All Ames testers are
factory lubricated. Do not
attempt additional lubrication.
Keep the tester dry and free
from oil. Store in the case
provided. When necessary,
wipe with a commercial
cleaner

Maintaining accuracy with a portable Rockwell hardness tester

All AMES Hardness Testers, whether in constant use or not, require accuracy checks. To check accuracy, take the average of 5 readings on the test block. The readings on the barrel dial should agree with the marking on the test block, within +/- 1 point.
Further, to guarantee the accuracy of your tester, it is recommended that tests be made in high, medium, and low ranges. For example, C Scale, C-63, C-50, and C-28. Once per year, your tester needs to be factory calibrated. 

The distance between the center of two adjacent indentations shall be at least three times the diameter of
the indentation.  The distance from the center of any indentation to an edge of the test piece shall be at least two and a half times the diameter of the indentation. In other words, keep indentations 3 diameters apart. Indentations can only be made on one side of the test block.

Please check out our penetrators for hardness testing by clicking the link below

Penetrators for sale

Also check out more on how to properly use a portable Rockwell tester by following the link below

How to properly use a Ames Rockwell Hardness Tester

You may also contact us with any questions you may have. 

This Video Explains How to Use Your Rockwell-Brinell Conversion Chart:

Rockwell-Hardness-Tester-Bench-Stand

Portable Rockwell Hardness Testing is Easier With the Bench Stand

Since 1947 Ames has been providing you with top-of-the-line portable Rockwell hardness testers for the hardness testing of various metals. We are committed to ensuring the accuracy of your measuring instruments. You can count on our help to get your job done in a safe and convenient manner. This accessory is made of 100% cast iron specially designed to fit any of your Ames Hardness Testers (with the exception of the Model 8 and Model 16 special testers).  The sleeve protects your tester from scratching and the no-slip bottom ensures you can use both hands to conduct your Ames test with no worries.

Ames Bench stand helps you get an accurate reading by removingl the awkward and challenging issues when trying to test your equipment.

  • Cast iron for solid support
  • Holds tester at a convenient angle, freeing hands for ease of use
  • Internal fiber sleeve protects handle
  • 11 lbs.

Looking for instructions on how to use our tester? Download our famous Rockwell tester manual.

Stillion Industries Acquires Ames Hardness Testers

Exciting news for our customers!

As of July 1st, 2019 Stillion Industries has acquired Electro Arc Manufacturing. This is good news for our customers. Alongside Stillion Industries, Electro Arc now has state-of-the-art ISO9001:2015 compliant machining and on-site engineering. With Electro Arc’s long history of quality product lines and Stillion Industries’ expertise in machining, we are positioned to make both companies reach new heights.

The move coincides with the retirement of Harold Stark, Electro Arc’s President/CEO since 1958, and ensures the continuation of Electro Arc’s tradition of quality.  Stillion Industries, active in the Ann Arbor area since 1972, brings expertise in machining as well as manufacturing know-how from Dexter Manufacturing Incorporated, which joined Stillion in 2014.

We have retained all employees from Electro Arc, doubling our workforce to maintain the long history and experience of both companies. Electro Arc has been in the Ann Arbor area since 1947 Stillion Industries since 1972. Electro Arc Manufacturing includes the Ames Hardness Tester and Uni-tek metal disintegrator product lines. The acquisition will ensure we are here to stay and we are committed to customer service.  We at Stillion Industries feel Electro Arc, Ames and Uni-tek are time tested superior products. We are committed to providing great customer service and a high quality
product.

We look forward to your ongoing valued business as we continue to provide a quality product.

Stillion Industries

Keith Stillion
President

 

Rockwell-Metal-Hardness-Tester-Calibration

Portable Rockwell Hardness Tester Calibration – An Infographic

Rockwell-Metal-Hardness-Tester-Calibration

 

Don’t forget to calibrate your Ames Rockwell Tester once a year for continued accuracy

To get your Ames Tester calibrated or repaired please ship it to:

Stillion Industries
2055 N. Lima Center Rd.
Dexter MI 48130
United States

Please be sure to put your contact information in with the tester shipment.

Metal Rockwell Hardness Testing

How to Test the Hardness of Steel

Rockwell Hardness testing can be used for determining the hardness of soft and harder metals including steel. The American Society for Testing and Materials (ASTM) has established a standard recognized worldwide to help manufacturers maintain the qualities they want in their products.  ASTM Standards E-18 and E-110 defines the test method and parameters for a valid test using portable hardness testers. Rockwell hardness testing is a way of measuring the hardness of steel. Hardness means resistance to penetration. This test gets its name from Stanley P. Rockwell who invented the test and the original hardness testing machines.

Using the Rockwell method to test steel hardness

The Rockwell hardness testing of steel parts is done by applying loads to parts via either a tungsten carbide ball or a  diamond indenter.  The surface of the steel part has to be ready before the testing can begin.  If it is not, the chances of inaccurate readings rise.

Next, a light load is applied to the indenter or penetrator (usually either 3 or 5 kg) to zero out the portable Rockwell hardness tester. Next, a heavy load ( from 15 kg to 150 kg) is applied and held for a period of time.

The length the indenter traveled from the application of the light load to the release of the heavy load is documented and used to determine the hardness of the steel

Rockwell hardness is determined by measuring the distance traveled by an indenter when a heavy load is applied to a heat-treated part. The Rockwell method is the most common and accurate way to get a calculation on the hardness of steel

Take a look at the video below for further instructions on using an Ames portable Rockwell hardness tester.

Further reading

What metals can Rockwell hardness testers be used with?

Ames portable hardness testers collection

Benefits of Using a Hand Held Rockwell Hardness Tester

Hardness calculations on metals and a are important for the manufacturing of different things: from automobiles to electrodes. Hardness qulaity control is used in various fields like machine engineering, metallurgy, mining and energy resource extraction.

Metal hardness measurements are performed with the help of stationary or bench and portable hardness testers. The operating principle of stationary hardness testers on Rockwell scales are described in the standards on the corresponding methods. Hardness tests on stationary hardness testers are direct measurements. Consequently, hardness tests performed using these methods are more accurate than the measurements via indirect methods.

Hardness tests on portable hardness testers are indirect measurements. Most portable hardness testers use the ultrasonic contact impedance method. The result of measurements on portable hardness testers is recalculated into hardness values on the Rockwell scales. Usually portable hardness testers have the following error limits of hardness measurements: ± 2 HRC on Rockwell scales.

The following is why portable Rockwell hardness testers have an advantage. Portable hardness testers are significantly lighter, they can measure hardness directly on a manufactured detail and in hard-to-reach places. Portable hardness testers are the only hardness testers suitable for conducting measurements in the field. One portable hardness tester enables the user to obtain hardness values using at least three different methods. The cost of portable hardness testers is lower than that of stationary ones. Important characteristics of portable hardness testers are repeatability and reproducibility of measurements. Despite relatively modest accuracy in comparison with stationary hardness testers, portable units have high reproducibility and repeatability and can be successfully used for components screening, control of the product homogeneity on hardness, as well as measurements in the field

There are several other ways for hardness to be measured, but the Rockwell test is the easiest one to perform. The portable tester provides an accurate measurement that can then be converted to a number on the hardness scale. The device is also highly versatile, and metals of nearly any size and shape can be used

Call or email us with any questions.

734-475-8527

UK +44 (0) 1384 231535

Email U.S. @ sales@electroarc.com
UK @ sales@electro.co.uk

The Rockwell Metal Hardness Scales Explained

You can use the Rockwell hardness test to test the hardness of materials. You will use the Rockwell test to perform tests on metals ranging from thin steel all the way to harder metals like Titanium. However, there are multiple scales to test in and these are identified by a letter ranging from A-V  Each scale uses a different indenter and load to perform the test.

When you perform a hardness test using the Rockewell scale, you can determine the hardness of metals and alloys of all kinds.  You will use a sphero-conical diamond penetrator or a hard steel penetrator which is forced into the part being tested with a predetermined pressure load and the readings represent the hardness numbers.

You can avoid errors in measurement due to surface imperfections or distortions at the periphery of the indentation with both minor and major loads.  The minor load of 10 KGS is applied first.  Remove the major load turning the handwheel back until the indicator hand is in position “set” on the dial.  The reading is taken from the barrel dial, which completes the whole operation in a few seconds.

The equation for the Rockwell hardness test for metals is below:  d=depth from zero load point.  N and s = various scale factors that can be found in the chart below.

Rockwell A scale

Used to test: Tungsten carbide.

Rockwell B Scale

Used to test: aluminum, brass, and softer steels

Rockwell C Scale

Used to test: harder steels.

There are other scales that are associated with a Rockwell superficial test. These scales use a lighter loads and shallow impressions to perform the test. These are used on testing very thin metals.

Ames Superficial Hardness Tester
Note: There is only one row of dial numbers for the Ames superficial tester.

Get an Accurate Reading With Ames Rockwell Hardness Test Blocks

To ensure your Rockwell metal hardness tester is performing at it’s highest efficiency you should perform accuracy checks regularly.

You can purchase standard or superficial test blocks in:

  • Brass

  • Hard Steel

  • Soft Steel

You can also request a specially calibrated test block. Ames offers the best quality hardness test block selection.  Every Ames test block comes with a certificate of calibration.

Our test blocks are manufactured to meet the highest standards including automotive and aerospace standards.  When you Match specific blocks to a specific penetrator, a set relationship is established, and they can be eliminated as potential variables in the hardness test system. When an issue comes up our blocks help you quickly and accurately determine whether your Rockwell hardness tester is the source. Each block has been calibrated on a tester whose accuracy has been verified using ASTM and N.I.S.T. traceable load and depth measuring devices. The individual test blocks are marked with their own unique serial number.  More information available upon request.

 

How To Use A Rockwell Portable Hardness Tester

Using An Ames Portable Metal Hardness Tester

Find more helpful videos on our youtube channel. Below is a transcript of the above video.  If you have any questions or need more information on our portable Rockwell testers than contact us here.

We’re going to be testing a customer’s sample piece on her Model 1 a standard Ames portable hardness tester.  The purpose of this demonstration is to show you just how easy it is to operate the tester as a sample piece or using a small clip. It is a hard material spring-type steel.  I’m using a diamond penetrator for the flat Anvil.   I’m going to be measuring in the C scale which requires a 10-kg minor load and I’ve got a  150 kg major load.  First thing I want to do is initialize the Dow indicator Itself by rotating the setting of the stylus of the indicator. Next we’re going to trap the part between the Anvil and the penetrator and I’m going to establish my 10 kg. load. Simply do that by rotating the handwheel and the pin correctly. Next we want to establish the zeo point on the tester itself. To do that we  rotate barrel down and rest the pin directly on the magnifer. Next we will rotate the handwheel to 150. Once that is set, reverse the handwheel back to the set point. What you see is the C scale numbers in black and B scale numbers in red. We are looking at the C scale.  You can see the line underneath the number 40 there’s a thick line and then off on the left hand side there’s little hash marks each one of those small hash marks is 2 points.  The large broad line underneath the number itself is the whole number or in this case 40.  You can see it set up in 10 point increments.  So what we’re looking at is 40 which is the black line underneath the 40 and then we’re sitting right between the broad and hash mark which makes it a 41.  We want to thank you for your attention should you have questions please feel free to contact us by email telephone.

Below are a few videos featuring tips on how to use a Portable Ames Rockwell Hardness Tester. Make sure  to tighten extensions, penetrator and anvil. Also make sure the gage is set to the dot. When used correctly our metal  hardness testers are reliable for testing metals and plastics.

If you should have any questions on our portable hardness testers please contact us here.

The first thing we are going to do is, with no load applied we want to lift this needle and make sure it’s below that set mark and pointed right at the dot. The next thing we’re going to do is just make sure all our components are tight so starting with the anvil, the extension and the anvil adapter and finally our penetrator, just make sure all of those are finger tight.

Is your Ames Hardness tester genuine?

How to tell if your Tester is a Genuine Ames Hardness Tester

Ames began making Ames Portable Rockwell Hardness Testers in 1947.  In 1975 Ames was acquired by Electro Arc.  The Ames line of portable hardness testers has been made in Michigan since.

In 1997 it came to the attention of the Electro Arc company that each of it’s testers had been purchased by a company in China and duplicated.  Now Chinese copies of Ames Portable Hardness testers are available online, bearing a striking resembelance to the handcrafted testers we manufacture everyday.  Each of our testers are built one at a time following the ASTM E110 standard for the Rockwell scale.  Each genuine Ames Hardness tester is individually calibrated to the Rockwell scales and bears a signed certificate with each tester.

Is your Ames Hardness tester genuine?

How can you tell if your Ames Portable Hardness Tester is genuine?

  • It bears the Ames symbol within the dial indicator
  • You bought it directly from Amesportablehardnesstesters.com
  • Call us with the model number located on the front of your tester – we keep records of every tester we sell
  • Check the documentation included with your tester

How important is metal hardness testing? Consider the information provided by hardness testing and its significance in structural (i.e. bridges), aerospace, automotive, quality control, failure analysis and many other forms of manufacturing and industry. Determining material properties provides valuable insight to the durability, strength, flexibility and capabilities of a variety of component types from raw materials to finished goods.

Hardness testing is used extensively to characterize materials and to determine if they are suitable for their intended use. Why then would you buy a Chinese copy of a hardness tester?

  •  When quality is critical, should you trust a counterfeit hardness tester?
  •  Can it be calibrated?
  •  Will it hold up?
  •  Can it be serviced?
  •  Does it really meet the ASTM standard?

Ames Hardness Testers can be repaired and calibrated at our facility in Dexter Michigan.  We also service Dell models.  We do not offer service for any other brands.  When considering a purchase of a Rockwell Hardness Tester to insure quality, you should consider its quality, repeat-ability and reliability.