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This article delves into the critical aspects of using and caring for thread and cylindrical limit gages to ensure accurate measurements and promote a longer wear life. Contrary to popular belief, limit gages are not indestructible. Gages will nick, scratch, burr, chunks of threads will break off if not handled properly along with changes in size if they are not stored properly.

Storing a gage properly is very important. Gages should always be stored in a manner that protects them from moisture and damage. Gages should always be kept in a clean, dry, and temperature monitored environment. Gages should be dipped in seal-peel, kept in a container, or wrapped in a manner that will protect them from damage. Nicks and burrs resulting from improper storage can significantly impact the gage’s accuracy and reliability.

Protecting your gages isn’t limited to just when they are being stored. It’s crucial to prepare your parts and gages for use too. This includes thoroughly cleaning both the product and gage threads, removing any extra material along with burrs or nicks from the parts.

When applying the gage, use gentle pressure – fingertip pressure is usually sufficient. Avoid forcing the gage as this can cause premature wear, or locking the gage and part together. Align the gage accurately with the product to prevent nicking the first thread or end of the gage.

After each use, return the gage to a clean surface. Never leave a gage on the machine where it can be exposed to coolant, chips, or be knocked to the floor. This could potentially cause major damage to your gage. You never want to hit your gage with a hammer, force your gage into the part, or use your gage as a tap/clean out tool. However, we all know that accidents do happen. When they do, you want to make sure to have the gage checked over and possibly have it sent out for re-calibration. Remember calibration of your gage is the number one way of knowing that you are using a good gage.

The frequency of gage calibration depends on several factors, including:

• Frequency of use
• Type of material being gaged (abrasive materials like brass and aluminum cause more wear than softer materials like 1012 steel)
• Type of coatings (some coatings are abrasive, while others can build up in thread roots)
• Size and fineness of the thread pitch.

Monitoring the gage’s wear history is crucial in determining the optimal calibration interval.

It’s important to remember that gaging costs are directly influenced by the care, usage, and control exercised over the gages.

Remembering these best practices for gaging will help with your gage’s wear life.

• Learn proper handling and use techniques.
• Maintain detailed records of gage use, calibration, and any observed damage.
• Thoroughly clean gages and parts before and after each use.
• Wipe off fingerprints to prevent corrosion.
• Store gages on clean surfaces and in separate containers.
• Store gages in moisture-proof environments.
• Recheck gages after any damage.
• Use the correct gage for the specific tolerance.
• Inspect gages before each use.
• Ensure gage and product temperatures are similar.
• Avoid forcing gages onto or into parts.
• Refrain from using gages as taps, dies, or for any other purpose than gaging.
• Never use gages as hammers or tools.
• Avoid spinning parts on or off the gage.
• Avoid wiping gages with dirty towels.
• Avoid cleaning gages in water or soluble solutions.
• Avoid leaving gages in oils.
• Avoid laying gages on metal surfaces, machines, or dirty areas.
• Avoid using sharp tools on gage coatings.
• Avoid using gages with improper markings.
• Avoid using gages with visible irregularities.

When purchasing gages, it’s crucial to select the correct gages for your specific needs. Utilize ANSI tolerance charts and consider gage maker tolerances. Avoid purchasing only “Go” gages, as this can lead to inadequate control. Invest in high-quality, corrosion-resistant gages. Calibrate gages using proper equipment and traceable standards. Keep final inspection gages separate from production gages. Never use master gages for production inspection.

By adhering to these best practices, you can ensure the accuracy, longevity, and effectiveness of your thread and cylindrical gages, ultimately contributing to improved product quality and reduced manufacturing costs.