Keyholes—also called dices, socket wrenches or of plinth— are an essential part of ratchet wrenches. Being interchangeable, they allow you to work with different sizes both in inches and in the metric system, and the different accessories available for the ratchet wrench make it a tool versatile and portable.
There are many tips and hacks for the use of keyholes; At DeMáquinasyTools we have compiled a guide of 10 questions and answers so that you can learn everything about them and clear up your concerns.
1. What is the best way to organize keyholes?
The keyholes They can be organized in many ways, but a very effective way, which allows any piece to be found immediately, is to follow an organization system according to different criteria, in order of importance:
- separate the keyholes according to the system of units (metric or imperial).
- Separate those groups, in turn, by the size of the socket.
- Each of the groups achieved in turn must be separated in its function (standard keyhole, deep, through, with electrical insulation, etc.). Also separate the accessories, if they are included among the pieces.
- Finally, order them according to size, from smallest to largest.
In this way, when we need a 3/4 pass-through keyhole for a 3/8 socket, we can locate it quickly just by following the same selection criteria that we use to organize them.
As for the storage stand, if you don’t have the original case, we can make a homemade stand out of a long enough strip of wood, with screws secured along it, with each measurement written below.
2. What sizes of keyholes are there?
While there are four sizes for the socket of the ratchet wrench, the measurements of the keyholes they are numerous.
There are basically two groups of keyholes: of imperial measures (inches) and metric measures. Socket size is always measured in inches (except for a few manufacturers that offer it in millimeters).
In the table above you can find the different measures of keyholes for each socket, divided into imperial and metric measurements.
3. How are the sockets attached to the ratchet?
Each keyhole has two ends: one, square, where it fits to the ratchet wrench; the other end is used to work on nuts, bolts and bolts.
The wrench crique or rattle It has a ball bearing at the end of which is held in tension by a spring. When placing the keyhole in the socket, this ball presses, holding the keyhole firmly.
4. What accessories exist? How are they used?
There are different accessories that allow you to carry out jobs that would otherwise be difficult to carry out.
The most common are augmenters and the reducers: if we only have one ratchet wrench of a certain insert size, with the enlargers and reducers we can use keyholes of other insert sizes. Reducers reduce the size of the socket square, while augmenters enlarge it.
Another commonly used accessory is the extender: it allows you to extend the depth to which the ratchet wrench.
The cardan coupling It is used for those cases in which the nut or screw is at an angle that is difficult to access; this accessory provides the possibility of transmitting torque at an angle.
There are also keyholes that in their work tip they have a screwdriver, which can be a flat tip, Philips, Torx, Allen, etc.
5. What care and what maintenance plan should keyholes receive?
The keyholes, like all metal parts, must be stored away from moisture, corrosive atmospheres and direct sunlight.
If possible, they should be kept clean and in their cases, ensuring that they close perfectly. If the case is not available, they can be stored on a shelf as long as they are covered with a light layer of mineral oil, to prevent them from rusting or corroding.
They should never be bumped or used for any purpose other than tightening or loosening bolts and nuts. As we will see later in this article, they should not be used either. keyholes common with impact wrenches.
6. How are extension bars used?
In a previous note we saw that the extension bars They allow us to reach nuts or bolts that are in places that are very difficult to access, such as inside a hole or between different parts of an engine. Remember that there are rigid and flexible extension bars.
Its use is very simple: just insert the extension into the ratchet wrench and by placing a keyhole at the other end. You just have to check that the lock (the small metal sphere in the socket) fulfills its function (otherwise the keyhole could come off).
7. My socket got stuck in the ratchet! What I do?
Don’t panic! This is a problem that can occur when the keyhole It presents rust or some dirt on its internal faces.
The easiest way to remove the keyhole is by heating it with a soft flame directly. It is best to do it with a liquefied gas torch, like the ones used by plumbers. As it expands as a result of temperature, the keyhole it will come loose more easily. If he keyhole it loosens but still won’t come off, you can tap it with a rubber mallet.
It is important to pay attention and apply the flame only on the keyhole, and never on the ratchet wrench or rattle.
8. Can common sockets be used with impact wrenches?
No way! The keyholes Common ones are not designed to withstand the impacts that occur in the socket area, and it is very likely that after a few uses they will break, which is very dangerous since the metal splinters can be projected at high speed.
Always use the keyholes specially designed for this type of use (keyholes which can also be used with ratchet wrenches common).
9. Are there keyholes with electrical insulation?
If it’s about keyholes covered on the outside with a double layer of rubber, which makes them suitable for working in special situations in which the fasteners to be handled are subjected to an electric current.
Anyway, be careful! Even with the cover in perfect condition, there is a risk of receiving an electric shock if special attention is not paid, because by their nature, the keyholes will have some exposed metal edges. Always work with the appropriate personal protection elements for this type of task.
10. I have a tight nut on top of a stud (threaded rod) and I can’t remove it with open-end or French wrenches; Are there keyholes for these cases?
Yes! Called pass-through keyholes, and due to their design, they can slide along a threaded rod without abutting problems.
Its operation is slightly different from that of the traditional keyholes: the fit is made through a hexagon carved on the exterior surface of the glass, thus making the interior, both of the ratchet wrench as of keyhole, are hollow and allow the passage of the rods.