There are many methods to measure hand inch, but in general, there are three methods, one is diameter method, the other is perimeter method, and the other is special ruler method.
1, diameter method
There are also two kinds of diameter methods, one is to directly measure the rings worn at ordinary times. Take the ring that you are comfortable to wear, lay it flat on the ruler engraved with the reading, see what the maximum diameter of the inner ring is, and then use the obtained diameter to get your own number.
The other is to measure fingers directly. Compare the diameters of fingers with a ruler. The scale on the edge of fingers is the diameter of the ring. Or use vernier caliper to measure the diameter of finger. But the diameter method has a disadvantage, that is, the error is relatively large.
Because everyone's joints are different, and the ring must pass through the joints, the size of the joints will also seriously affect the size of the ring.
2, perimeter method to measure the size of the ring.
Perimeter method can also be divided into three types according to the different materials used. The simplest method is the paper strip method. First, wrap a small piece of paper on your finger, then cut the paper and straighten it, measure the length of the paper with a ruler, and then compare it with the ring size comparison table to get the size. Use rope, rope is the same as paper. After winding, measure the length and compare the dimensions.
Both of the above methods have a disadvantage, that is, there are still some errors in measuring the circumference of the root without going through the joint. So the third is to measure with iron wire. Use wire to simulate a ring and make a circular iron ring on your finger. Try to put on and take off the hoop several times. After the tightness is moderate, fix the iron ring and mark it at the lower left. Take off the iron ring and spread it in a straight line, then measure the length, and then get the hand size according to the comparison table. It is best to use inelastic copper wire. This method has the smallest error, but the material is not easy to find.
3, ring size measurement method ruler measurement method
General stores will have special rulers. Put the ruler on your finger, adjust the size, record your reading, and then the value you get is the size of your hand.
If your hand inch is measured with a special ruler of a specific brand, it must be accurate. But if it is the measured diameter or circumference, it must be compared with the ring size comparison table of the corresponding brand to get the accurate hand inch. The key problem is that different brands use different standards in the ring size comparison table.
Ring size comparison table standard
At present, the hand-inch standards adopted by major brands mainly include the following.
1, perimeter method
The perimeter method is determined according to the perimeter of the ring, and the value obtained by subtracting a specific value from the perimeter is the size of the hand. Here are several standards. Chinese mainland's standard is perimeter minus 40. For example, the circumference of 44mm is No.4, and the circumference of 62mm is No.22. Many brands have guessed this unified standard, such as "Zhou Shengsheng", "Thomson" and "Old Silver Village".
2, the inner diameter method
The inner diameter method, as the name implies, is determined according to the diameter of the ring inside the ring. Subtract a specific value from the diameter to get the ring hand inch. Generally speaking, this value is 10mm, that is, a ring with an inner diameter of 15mm, a ring with a hand shape of 5, a ring with an inner diameter of 2 1mm and a hand shape of1. Many brands adopt this standard, such as "Stone" and "Keira".
3, the inner diameter increase method
The way to increase the inner diameter is to increase the diameter by a fixed length for every number added on the basis of a certain value. Brands with different standards will have different starting standards. For example, in the "Silver Age", the diameter of No.4 was 1.42cm, No.5 was 1.45cm, and No.6 was 1.48cm, and each number increased by 0.03cm.
The ring size of Mankalong Jewelry is also based on the increasing inner diameter, from 6# diameter 14.05mm, 7# diameter 14.4mm, and 8# diameter14.75 mm ..................................................................................... ..
4. Increasing perimeter method
The perimeter increase method, like the inner diameter increase method, is based on a certain amount, and each increase in perimeter will increase by a fixed length. For example, "Chow Tai Fook", the circumference is in inches, and the fixed length is increased. The circumference of Chow Tai Fook No.9 is about 2.08 inches, that of 10# is about 2. 12 inches, and that of 1 1# is about 2. 16 inches. By analogy, each additional one will increase by 0.04 inch.
American standards are also based on the algorithm of increasing perimeter. First, the perimeter of No.4 is equal to 1.85 inches, that of No.5 is equal to 1.95 inches, and that of No.6 is equal to 2.05 inches. ...