Comparison Tekhmann TRH-1120 DFR vs Tekhmann TRH-1120

The type of cartridge used in a rotary hammer to hold a working tool.

— SD+. Abbreviation for it. "Steck-Dreh-Sitzt" — "insert-turn-fixed." Today's most common rotary hammer chuck, used in low and medium power models. It has a 10mm diameter shank with 4 slots and accepts tools from 4 to 26mm in diameter and 110mm to 1000mm in length. The advantages of SDS + are the reliability of fastening and convenience when changing tools — it does not require additional devices such as keys. The main drawback is the significant beating of the tool during rotation, due to which such a cartridge is very poorly suitable for drilling.

— SDS Max. Modification of the SDS + cartridge (see above), intended for use in powerful professional models. It has a shank diameter of 18 mm and allows the use of tools with a diameter of up to 55 mm; otherwise similar to SDS+.

— SDS-Quick. A variation of the SDS cartridge (see above), in the shank under which protrusions are used instead of grooves. It is also possible to install tools with 1/4" hex shanks in such a chuck. The most common tool diameter for SDS-Quick is 4-10 mm. This chuck is used relatively rarely.

— Quick release. Chuck for holding drills and other tools used in drilling holes. The design is similar to those used in electric drills — it has 3 cams, it is designed for a too...l with a cylindrical shank without grooves, and hand force is enough to install / remove the tool. Such a cartridge is devoid of the main drawback of SDS — beats during rotation; this allows you to use the rotary hammer for drilling with good quality. On the other hand, it is much worse for chiselling than SDS. Therefore, keyless chucks are usually supplied as an accessory and are installed instead of the standard SDS chuck.

— Key. The presence of a special key cartridge in the delivery set of the rotary hammer, usually in addition to the standard SDS (see above). In terms of mounting design, this chuck is similar to the keyless chuck (see above) and is also designed for use in drilling. Its main difference lies in the method of installing / removing the tool: you can’t do this with your bare hands, you must use a special key to compress / unclench the cams. Such a system is somewhat more reliable than a quick-clamping system, but much less convenient: changing a tool takes a lot of time, and the key can be lost.

Possibility of quick replacement of the perforator chuck — usually from a regular SDS to a quick-clamping one (for more details, see "Chuck type"). Such replacement is carried out in a few seconds and does not require additional tools.

The maximum tool diameter that can be used with a rotary hammer when drilling in concrete. See "Maximum drilling diameter in wood" for details.

The maximum tool diameter that can be used with a rotary hammer when drilling with a hollow core. Crowns are used to create holes of large diameter (from 40 mm) in hard materials such as reinforced concrete and stone. See "Maximum drilling diameter in wood" for details on the maximum diameter.

— Additional handle. The presence of an additional front handle on the hammer drill, usually located at the base of the chuck. This handle can be non-removable or removable, rigidly fixed or movable. Holding two handles with two hands is much more convenient than holding one and the body, as it allows for optimal distribution of the load on the hands; this is especially important during long-term work and processing of “heavy” materials.

— Depth gauge. A device that allows you to make holes of a strictly defined depth in one go, without constant measurements and without the risk of drilling deeper than necessary. Usually looks like a rod fixed to the body of the hammer drill parallel to the working tool. When used, this rod extends to such a length that when the desired depth is reached, it rests against the surface of the material being processed, preventing the drill from moving further.

— Chisel. Complete attachment for impact work with a hammer drill in the manner of chasing, leveling hard surfaces, chipping tiles, bricks, concrete, etc. Different types of chisels are produced for different tasks — flat, blade, groove, crushing peaks with a sharp tip.

— Boring bit. The presence of Boring bit in the delivery set of tool designed for processing various hard materials by drilling with impact. Buying such a s...et eliminates the need to look for a drill separately, but the characteristics of the complete attachment must be clarified before purchasing, since they may not meet the buyer's requirements.

— Charger. The presence of a charging unit in the kit allows you to charge batteries. Accordingly, for models with batteries, this accessory is necessary to power the battery. However, there are models without a charger. And hammer drills with it can differ in the model of the charger, the name of which will allow you to learn more about its characteristics and, if necessary or as needed (breakdown), buy a similar one.

— Case included. The delivery set includes a special case that facilitates storage and transportation: it provides protection from impacts and adverse conditions (moisture, frost), is equipped with a special handle for carrying, in addition, in the case, along with the hammer drill itself, a set of working tools, replacement cartridges, etc. can be placed.

— Dust collector. The hammer drill comes with a special dust collector. As the name suggests, it is designed to collect dust generated during operation, which could otherwise cause significant inconvenience. It usually looks like a bag or container attached to the body; it can be either replaceable (thrown away with the collected garbage) or permanent. The dust collector slightly increases the weight and dimensions of the hammer drill, but it can be removed if necessary.

The weight of a fully assembled rotary hammer (in the case of battery power, with a standard battery installed). Unlike many other types of equipment, in the case of rotary hammers, light weight is far from always an advantage. So, heavy models are better suited for professional use — they are less prone to vibrations and, usually, are stronger, which is important when working with difficult-to-cut materials for a long time. But for small, simple works of short duration, a lot of weight is not required, and in this case, light models are useful, which do not require significant effort to hold on weight.