Ultimate Guide on How to Calibrate a Metal Detector

Metal detectors are used almost in all industries that produce what the public uses and the benefit of using these machines are for prevention. Though other experts use metal detectors to search for fortunes, iron, and coins, no one can ever predict how the metal detector machine works.

Calibrating detecting machines is necessary for whoever wants to go out for a successful hunt. Companies that want to satisfy their customers without getting them injured or end up receiving complaints on a product always make sure they calibrate their metal detector before usage.

In this article, I explained more about detecting machine calibration and how it is used to check unwanted equipment. To learn more about calibration, read me now…

What is a Metal Detector 9 Point System?

A metal detector 9 point system means testing and retesting a metal detector to get the appropriate setting for specific hunting or scanning. The word 9 points in this context means checking if the product you are scanning has any error in the nine positions.

Since the 9 point system is used for scanning products to check if obstructive material is in them, industries like food, apparel, and more use the metal detector and the 9 point system for calibrating their detecting machine before use.The table below illustrates the shape of the detecting machine and how the product has been positioned before it will be qualified for moving out of the factory.

Metal Detector 9 Point System

Metal Detector 9 Point System

The purpose of using the 9 point system is to prevent the distribution of contaminated products.

Metal Detector Calibration Standards

The metal detector calibration standard is the act of complying with international standard rules that are set out as the general requirements for the competent, impartial, and consistent operation of industries using the detector.

To make your industry’s metal detector calibrated and certified, you need to contact a third-party calibrator, an ISO 17025 certified and NABL accredited External agency. Third-party calibrators certified by iso or NABL accredited External agencies you can get for calibration include: American scale company LLC, Cross precision measurement and Fastec services, LLC.

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Overview on Metal Detector Policy for Garment Industry

Needle and Metal Contamination Policy:

The metal detection policy is regulated to ensure companies producing garment apparel are free of any broken needles or metal parts that could cause an injury to consumers buying and using their products.


In this part of the policy, the garment industry is required to always check their product correctly before distributing it to end-users. One of the reasons why prevention policy was mandated is that if a worker detects a needle is broken, they must fill a broken needle control log immediately. 

The data in the control log include date/time of the incident, production line, operation, operator, machine type, machine id, mount broken needle, panel/garment destroyed, yes or no, mechanic’s signature, and date.


The detection process is where the factory tests all the products produced if there is metal or needle in them before it is packaged for distribution. When testing at this period, the operator operating the metal detector machine must take away any metallic material around the detecting machine.

The policy stated that the detecting machine should be moved far away from the product during this process to prevent mixing up checked and unchecked products. In addition, the purpose of detecting is to prevent end-users from getting injured when using the product.

9 Point Calibration Process

9 Point calibration process is the primary task that occurs every day and every time before checking the products. It is a process where supervisors check if the detector is functioning correctly and operating at the correct sensitivity (1.2mm). According to policy, a 9 point calibration process is recommended to be done two times a day by a supervisor and fill in the control log to input the test result.

US Location for Metal Detector Calibration Services

Did you even need a specialist to help you calibrate your metal detector, or did you want them to help you diagnose yours? Below is the address, website, and contact of companies that offer calibration services for metal detectors in the United state (US).

1. America scale company LLC

Website: americanscaleus.com

Contact: contact link

Toll-Free: 888-205-1059 (24/7)

Direct: 704-921-4556

Fax: 704-921-4552

Email: amscale@americanscalenc.com


Charlotte Office:

7231 Covecreek Dr

Charlotte, NC


Raleigh-Durham Office:

8098 Old Middlesex Rd

Bailey, NC

2. Cross precision measurement

Website: crossco.com

Contact: contact link or call 855.889.0092

Address 1:

10940 Beaver Dam Rd,

Cockeysville, MD 21030

United state.

Tel: 410.666.3200

Address 2:

Cross Precision Measurement:

1712 12th Ave. North,

Suite F, Bessemer,

AL 35020

United state.

Email: sales@crossco.com

3. Fastec services, LLC

Website: fastecservices.com

Address: Office & Repair Center

750 Circle Drive

Travelers Rest, SC 29690.

United state.

Tel. 843-406-9745

Tel. 864-836-3600

Mail: Enquiry@fastecservices.com

4. Capital calibration

Website: capitalcalibrationservices.com

Contact: contact link

How to Get a Metal Detector Calibration Certificate

Since metal detector machines are used in many industries such as food, beverage, pharmaceutical, and other industries, you must calibrate to know what suits your service and get a certificate that will make your organization a certified user of the metal detector.

To get a metal detector certificate for your industry, you will need the visitation of a specialist that offers such services. Companies like MWS, American scale companies, and Cross help organizations test their metal detecting machine.

Step by Step Guide on How to Calibrate a Metal Detector

There are different types of calibrating machines used for various purposes. Some are used in industries such as food, clothing, etc., while others are used to find gold, silver, coins, and artifacts.

Even though the detector’s major thing is to detect iron and needles, they work differently, their structure is different, and the calibration process is quite different. In this section, I will explain how to calibrate a metal detector used in industries and the one used for searching for fortunes.

Easy Steps on How to Calibrate Hand Held Metal Detector

Suppose you want to be an expert or professional metal detector user. In that case, the best option is to always try to calibrate your metal detector so that you can know the kind of result that will show up when you use your detecting machine on a specific thing during a search.

The purpose of calibrating is to know the setting of your detecting machine and how it reacts to a specific thing found in the ground. Before you start calibrating a handheld metal detector, you will need to have a person standing in front of you and iron or coin on his body. How Do Metal Detectors Work

  1. Turn on the calibrator and give it some minutes to warm up.
  2. Ensure the person you want to use to test the detector is standing.
  3. Check the person’s front side by scanning from the left shoulder to the feet and from the right foot to the shoulder.
  4. Repeat the process on the backside.

Note: always retest an area if the detector beeps a sound during scanning.

How to Calibrate a Metal Detector 9 Point System

According to the definition above, the 9 point system is the process of calibrating a metal detecting machine by positioning it into four different areas: top, middle, bottom, left, right, and center. 

The reason why it is called a 9 point system is that the machine is triangular. Below is how to calibrate a metal detector. Before you start calibrating, you will need the equipment listed below:

  • A Test card – 1.2 mm or 1.0 mm diameter ferrous metal standard.
  • Calibration block – 60 60 90 mm

After providing the testing equipment, place the test card on the conveyor belt as it was analyzed in the table below to test.  

Step 1: Place the test card only.

Firstly, place the test card only on the conveyor belt to calibrate the detecting machine. When placing it for the first test, you must start with the A1-A2-A3 level, after which you can follow the step explained below.

Step 2: place the test card on the calibration block vertically

After calibrating the metal detector using the test card only, the next thing to do is to repeat the same process you did in step one but with a different placement.

In step two, you must place the test card vertically on the calibration block or insert it into the calibration block if it has a space on its body and calibrate it at the A4-A5-A6 position.

Step 3: place the test card on the calibration block horizontally

This is the final calibrating process where you will stop the process and start the process another time. Place the test card on the calibration block horizontally and calibrate it at the A7-A8-A9 position.

Note: make sure you retest if any point is not detected during the testing period. The purpose of retesting is for you to understand how the machine works.

Needle Detector Machine Calibration Procedure

Needle detector machine calibration is a machine that apparel and garment industries must-have. The needle detector is used to check if needles, broken needles, or metal is in a cloth so that the brand can remove it and prevent injury that may occur. Below is the needle detector calibration procedure:

To calibrate your detecting machine, the first thing you need to do are;

  • Firstly, turn on the detecting machine.
  • After this, place the test card only on the conveyor belt and test it at position A1-A2-A3 to check if the detecting machine is working perfectly.
  • After testing using the test card only tod8 calibrate the machine successfully, you can now use the test card and calibration block to perform another test.
  • Place the calibration block vertically on the conveyor belt and place the test card on it to test it at position A4-A5-A6.
  • This is the last part of the nest where you will place the calibration block vertically and run the test at position A7-A8-A9.

Note: when testing the card on each position, if it is likely that position A6 or another doesn’t beep a sound, kindly retest it to ensure there is not an error. Make sure you fill in the control log for your test result.

How to Calibrate a Metal Detector at Home

The equipment listed below must be provided to calibrate a metal detector at your house.

  • Metal detector
  • A metal or garret OTP

After the provision of the equipment, then you can now turn on your detecting machine, select the type of elimination you want to use ( standard or discrete trash), then start moving the metal on the surface of the detecting machine coil for testing in elimination level. read also White’s Treasure Pro Metal Detector Cost

How to Calibrate Garrett Metal Detector

To calibrate a Garrett metal detector for better usage, you will need a coin, medal, gold, or a piece of rock and a Garrett detector itself when calibrating a Garrett metal detector. After providing the time listed above, you can now do the next thing below.

  • Select a program you want to use in your calibration process.
  • Test detector sensitivity by placing a key or iron on your hand or part of your body.
  • Then walk through the detector pole.
  • The detector must alarm on items you wish to detect

How to Calibrate Fortress Metal Detector

When calibrating a fortress metal detector, you need to consider levels of testing, including clean product and contaminated product (metal – ferrous). Clean product signal ranges from 0 – 100 while contaminated products are 100 and above. Even though the clean product signal goes from 0-100, it should always be under 50 when testing it to avoid false positives.

The metal test can range from 120 and above when calibrating, while ferrous could be from 322 and above. Before you start the calibration, Turn on the metal detector to warm up for 5 – 10 minutes, after which you can now click on the calibrate button twice to start calibrating. After clicking the calibrate button twice, the display box will show a fast learn mode; you can now run a product on it.

Immediately the metal detector scans the product; the machine display bar will show fixed, indicating the calibration is complete. Once you see the fix, you can now check the level of the product if it is a contaminated or clean product. 7 Stores to Buy White Metal Detector Replacement Battery

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