The reliability of handheld tools like calipers is frequently required in many areas that need higher accuracy and precision such as in engineering, metrology, manufacturing, quality control, 3D printing, etc. However, behind its advantage, these measuring tools are important to keep them well maintained to give accurate readings with extended life.
The care includes regular inspection calibration, how to store it well, how to avoid wear, and many more. Some of the maintenance and care require a frequent day-to-day basis while some require a certain interval.
Basically, these handheld calipers require two categories of care:
- Ensuring the use of the correct tool for the correct purpose to ensure that the caliper stays accurate.
- Another type of care is in the form of periodic, formal, and documented inspection of the caliper.
It’s also worth mentioning that each type of caliper requires a different threat. Therefore, we also consider the care of each caliper type in this article. These are the guide to take care of (vernier, dial, and digital caliper).
1. Regular Inspection and Calibration
Calibration of the caliper is done in-house, but many quality control programs refer to testing labs for professional calibration. These labs calibrate and service the equipment as per standards. It ensures periodic, formal, documented inspection of the caliper. The best practice is to send your caliper to an ISO 17025 accredited calibration lab.
This calibration is either done on newly procured calipers or such calipers that experience a shock or drop. It is done as per practice set in a company. Companies follow either their own calibration standard or international standards (ISO etc.).
Use of Gage Blocks in Calibration
Caliper calibration mostly takes advantage of gauge blocks. These blocks are precisely manufactured from steel or ceramic with approved dimensional tolerances. Simply said, compare the caliper’s reading you take with a known gauge block length.
If you want to calibrate the caliper yourself, at least, you have to use the appropriate grade. The grades represent their accuracy and price.
It’s also important to keep the gauge blocks well stored as well as avoid dragging one gauge block to another that may disturb their dimension. In other words, use the storage box. A gauge block set should always come in a storage box. Moreover, you should wear white gloves to handle gage blocks to avoid corrosion.
2. Avoiding Wear
Wear is caused when the caliper is handled without care, this includes no use of gloves or not washing grease or oil off hands prior to handling the caliper. This leads to the deposit of foreign matter that causes the tool to wear. Wearing white gloves can nullify this issue and protect the caliper.
The proper handling of calipers is always an effort that results in accurate performance. The calipers that are taken care of will provide better performance, extended life, and require less calibration. All these factors directly influence quality and productivity in a firm.
3. Care Based on the Type of Caliper
The calipers can be manual, digital, or dial and they require a different type of care which varies due to their mode of operations. The following paragraphs will highlight the procedure of care for a vernier caliper, digital vernier caliper, and a dial vernier caliper.
– Care of Vernier Caliper
Routine care and maintenance of the vernier caliper that you bought ensure functionality and consistency. It saves the equipment from unnecessary or unexpected malfunctions. Apart from the correct storage of the vernier caliper, you need to put attention to the following points to ensure brilliant care.
1. Don’t pair vernier caliper with other tools
Vernier caliper should not be used with heavy tools like drilling or cutting tools, hammers, and files. Moreover, Vernier should not be placed on lathe machines to avoid both damages to the tool and potential accidents.
2. Don’t expose the vernier caliper to temperature changes
Temperature can cause errors in the readings of a vernier caliper. This is because the material of the caliper may expand or contract due to temperature. Therefore, both the subject specimen and caliper should be at the same temperature.
Prolonged exposure to sunlight due to poor storage practices can cause thermal expansion of the caliper. Moreover, exposure to heat because of an electric heater, furnace, or any such equipment leads to permanent damage.
3. Correct application of vernier caliper
Vernier caliper should only be used for dimensions where it is applicable. It is a common practice to use a vernier caliper as a foot scale, which is wrong and it damages the caliper. Therefore, care should be exercised that it is used only for the purpose it serves.
4. Don’t try to repair the vernier caliper on your own
One should never try to repair a caliper if they are not trained for the purpose. Repairing on one’s own may cause bending, corrosion, or uneven measuring face. It is recommended to get the caliper calibrated or repaired from certified labs.
5. Don’t measure inaccessible dimensions using vernier calipers
Be careful about the location you are taking measurements from because inaccessible locations might damage the caliper. Moreover, the use of the vernier caliper for measuring inaccessible dimensions disturbs the calibration of the Vernier caliper.
6. Ensure proper cleaning of vernier caliper after use
Vernier caliper should be cleaned and made free from dirt or other particulates that may settle after every use. Use a rust-free lubricant to protect the steel caliper from rusting. Moreover, place it in a moisture-less place to avoid rusting.
7. Proper servicing of vernier caliper
A Vernier caliper must always be sent to certified labs for servicing to check for the correctness and functionality on regular basis. This aids in extended use of the caliper without compromising its accuracy or performance.
– Care of Digital Caliper
Digital vernier calipers have become increasingly common in homes, shops, and industries. This is because digital calipers provide extreme ease in measuring, anytime and anywhere by anyone, as measurements do not involve extra calculations.
However, due to their precise nature, even a minor issue can lead to great fluctuation in its readings. This is why users need to take good precautions and take extra care of digital calipers. Tips for taking care of any digital vernier caliper are as follows:
1. Measuring guide to digital Calipers
Even though it is very easy to take measurements with a digital caliper but it is advised to take precautions while doing so. Never apply excessive force on the jaws of the caliper. This leads to a definite decrease in the accuracy of the instrument.
The object being measured should be placed high up between the legs of the caliper instead of its tip to avoid excessive force on the jaws. Care should be exercised in adjusting the jib screws of the caliper so that the jaws are not loose.
2. Electronic maintenance of digital calipers
The calipers face issues because of their batteries or electronic assembly. The battery should be replaced as soon as the caliper shows symptoms like static, flashing, or no display. The battery contacts should be cleaned to avoid corrosion.
The digital calipers should never be repaired on one’s own. Instead, they should always be sent to certified labs for testing and rectification for maintaining their level of accuracy and enjoying the extended life of such calipers. If you can afford it, try to send your digital caliper to an ISO 17025 accredited calibration lab.
3. Dealing with zero errors in digital calipers
It is a commonly experienced issue in digital calipers which can be eliminated by a “zero button” provided on the caliper to reset the error. To ensure proper remedy, the process should be done several times to reset the error of the caliper.
Before zeroing, hold the jaws in front of a light source to ascertain if the jaws have any gap between them. In case the light passes, there is a need to either press them together or (if possible) send them to a lab for grinding to a smooth finish.
4. Storage of digital calipers
Water and moisture will adversely affect both the metallic body and the electronics of a digital caliper. Therefore, the caliper should be properly cleaned with a dry and soft cloth and the caliper should be protected from damp conditions.
5. Handling of digital calipers
The digital caliper should be handled with a light hand as compared to the manual caliper. The jaws should not be pressed with excessive force. It is advised to wear white gloves while using such calipers to save them from dust and moisture.
– Care of Dial Caliper
Dial vernier calipers are a type of analog calipers which show the readings it takes on a dial. These calipers operate on a rack and pinion arrangement and therefore require good care to uphold the level of accuracy. The following must be done for good care.
1. Calibration checks on dial calipers
The calibration of dial calipers must be checked on a daily basis and proper training for calibration is important because this caliper requires frequent calibrations. This would ensure that it maintains its accuracy.
2. Handling and cleaning of dial calipers
Check the beam of the caliper for any residue or dust after and before usage. Clean the beam with little oil using a clean soft cloth to ensure that the rack and pinion mechanism does not get stiff. Use gloves while handling for protection.
3. Storage of dial calipers
Care should be taken in ensuring the storage of dial calipers somewhere dry and moisture-free. Use the protective plastic provided with the caliper for storage. Proper cleaning prior to storage is advised and always store at room temperature.
Like other workshop tools and measuring instruments, a caliper requires consistent care and maintenance. These threats can prolong the caliper life and retain its accuracy. Whichever the type of caliper you have, they are the same in terms of regular inspection and calibration requirements. Besides, since their working systems are different, further care also needs your attention accordingly. Those are the tips you can have in mind when it comes to taking care of your caliper.