How to Choose Bits for Screwdrivers

You have purchased an electric screwdriver for your workshop or for your professional activity - carpenter, woodworker, mechanic - and now you need to choose the inserts to use in daily work. The quality of the tool must go hand in hand with the quality of the accessories you use to transmit the rotational force to the various elements to tighten and loosen. With the right precision.

Because, in the end, that's what we're talking about, right? Inserts are nothing but the medium to ensure that rotation is transferred from the tool to the screw or bolt. The quality of the inserts must guarantee that the force is not lost and that the torque is transmitted directly to the mechanical element. That's why it's so important to understand how to choose the right inserts for tightening and loosening.

Number of inserts needed

Let's start by clarifying a point: what is the right quantity of elements to buy? There is no right answer, or rather: if you want to work well, you shouldn't try to save money and try to adapt an insert to a job it can't do. So no forcing.

You risk ruining the screw and stripping the bolt, and at the same time you ruin the insert. On the other hand, it's useless to buy an oversized insert kit, carefully evaluate your work and get the right quantity and quality of accessories for your screwdriver.

Insert impression

One of the parameters you need to consider when choosing your inserts: the shape of the impression that must match the element you decide to work on. In addition to the size, you need to consider the model which can be a classic slotted or Phillips cross screw or a more articulated solution such as Torx pins with or without hole or in plus version, hexagonal, Pozidriv and much more.

The options are diverse and you find them in this graphic taken from the LTI catalog. Having a good number of profiles for your inserts is important so you can complete every job in the right way, without forcing or improvisation.

Accessories for use

Sometimes an excellent insert becomes unusable if you don't exploit it with suitable accessories. Like, for example, extensions that allow you to easily reach distant corners. Or maybe the joints that operate at a particular angle.

Conditions are not always useful to operate in a straight line: make sure you have the right angle adapters but also the adapters useful to never improvise and always be able to intervene properly. Because that's how a professional works.

Material of realization

A fundamental point when choosing the screwdriver inserts suitable for your purpose. The basic advice is this: it's worth buying tools created with resistant metal alloys, just like those used by LTI inserts offered by Krino.

We need to optimize the hardness and toughness ratio and to do this we don't just use high-quality materials like stainless steel or Chromium-Molybdenum-Vanadium thermally hardened in-house. The processing is done with CNC lathes, tools designed to perform high-precision operations that guarantee the inserts maximum adhesion with the element to be tightened or loosened.

Insert feature

An important decision must be made regarding the specific characteristics of the insert. In summary, in addition to tightening and loosening, what are the requirements to observe? It depends on the uses and the needs of whoever has to perform the operations.

For example, you might need inserts for impact drivers capable of withstanding the force of these tools (like the Pulsar models). Or in some circumstances, it can be useful to use inserts with magnetic element that holds the screw and facilitates work in difficult situations. Another important model: the one with titanium coating.

Then there's the one capable of withstanding high torque spikes (an LTI example). For critical uses there are also inserts with diamond coating, which reduce the cam out effect because the tiny diamond particles get a grip in the screw cavity.