To avoid stripping a bolt, you must use a socket that match the bolt head size correctly. Using a socket that is too large for the bolt heads can damage the bolt head; the socket may round the corners of the bolt head. Using a socket that is too small for the bolt head will prevent you from placing the socket upon the bolt head at all.
Therefore, you must measure the bolt head to ensure that the socket will provide a snug fit to the bolt head. To measure the bolt head correctly, measure from one flat side of the bolt head to an opposite flat side of the bolt head. Measuring from corner to corner of the bolt head will result in an incorrect measurement.
How to Choose the Right Socket and Ratchet
If you are not certain of the size of the bolt head, use calipers to measure the flat of the bolt head. By measuring the flats of the bolt head, you can ensure that you will select the appropriate sized socket for that bolt. Additionally, taking the time to accurately measure the size of the bolt head will prevent the bolt head from becoming a damage mess.
The SAE system use inch-based measurements for bolts and sockets. For instance, a standard 3/8-inch bolt will require a 9/16-inch socket to proper fit into that bolt head. For this type of bolt, you will need a 3/8-inch drive ratchet.
Some bolts will be heavy duty hex bolts. Heavy duty hex bolts are larger than standard bolts. Thus, a socket for a heavy duty bolt will have to be one eighth of an inch larger on the flats than a standard bolt of the same size.
Sockets may also be metricized; however, using a metric socket on an SAE bolt can lead to slop in the bolt connections over time. The metric system use measurements in millimeters for bolts and sockets. Small metric bolts, such as M5 and M6 bolts, will require 8mm or 10mm sockets, respectively.
Additionally, you will need a 1/4-inch drive ratchet for these type of small bolts. Larger metric bolts, such as those that are M12 in size, will require 18mm or 19mm sockets. For these bolts, a 3/8-inch drive ratchet will be needed.
Finally, very large metric bolts, such as those that are M20 or M24 in size will require 30mm or 36mm socket, respectively. For these very large metric bolts, you will need a 1/2-inch or 3/4-inch drive ratchet. The socket design can have an effect on the amount of torque that is place into the bolt.
For example, a six-point socket will grip the flats of the bolt head very tight. A six-point socket will be best used for bolts that are rusted or seized. Twelve-point sockets are useful in instances where there is limited space to place the socket onto the bolt head; however, twelve-point sockets have the potential to pinch the corners of the bolt head if too much torque is place into the bolt using the twelve-point socket.
Deep sockets are useful for situations in which there is long studs to be accounted for, while pass-through sockets can be used in situations in which long rods need to be tighten. Impact-rated black sockets are used with air guns. Additionally, chrome hand sockets should not be used with power tools as they can easy shatter.
It is essential that the drive size for the ratchet match the amount of torque that is required by the bolt. For instance, you use a 1/4-inch drive ratchet for tasks involving light work, such as bolts of 5/16 inches in size or less. A 3/8-inch drive ratchet is used for general automotive work; it can handle bolts that are between 3/8 inch and 9/16 inch in size.
A 1/2-inch drive ratchet will be used for heavy-duty vehicles and components, such as suspension components or lug nut, for bolts of 7/8 inches in size or less. Finally, a 3/4-inch drive ratchet is used for industrial equipment components that require very large bolt. Using a drive size that is too small for the bolt will result in the drive size for the ratchet snap.
To properly tighten bolts and avoid damaging the bolt heads, you should utilize some habits. For instance, you must ensure that the socket is seated onto the bolt head prior to applying any force to the bolt. If a bolt becomes stuck, you should treat it with penetrating oil for ten minute prior to attempting to loosen it.
It is also important to use a torque wrench when tightening bolts to the correct specification. Finally, it is essential to ensure that the bolt is of the appropriate size for the component into which it is to be inserted, using calipers to ensure the size of the bolt head, or by ensuring that the specifications of the component indicate which size bolt is to be used.
