Hole or crown saws represent a rather specific segment of the tool, which is due to technical and operational features. If classic saws work with cutting equipment that implements a direct cut, then the ring tool performs circular cutting. Incidentally, this makes such models similar to traditional drills. In the process, a hole is also formed, only of a larger diameter and with minimal mechanical impact on the structure of the material. More importantly, the circular saw thanks to the design of the nozzles allows you to cope not only with cutting wood billets, but also with concrete, metal and even stone.
Structural Features of Hole Saws
The ring-type sawing complex is formed by two basic components. First of all, this equipment, due to which a force action is given, which makes the nozzle rotate. The main functional element is the cutting blade itself. This can be a set of crowns for wood of different sizes, and universal canvases for a wide range of building materials, providing for the possibility of adjusting the diameter.
A mandatory component connecting the power tool and the saw blade is the holder, or shank. The saw is screwed onto the holder before the workflow, and after it is untwisted with a hex wrench. In this case, fixation mechanisms may differ. Hexagonal holders are suitable for use with conventional drills, but more modern designs are integrated into the system using the SDS-plus keyless chuck. After completion of the work, the circular saw should be released from the cut-off part of the material that entered the empty niche of the crown. To perform this operation, a special spring is intended. Sawing products can also be removed manually. This method is carried out through special slots on the sides of the saw blade.
Technical specifications
In the ring system, only one parameter remains constant and unified - this is a height of 40 mm. Depending on the design, it allows you to cut holes with a depth of about 32-37 mm. The main characteristic is the diameter of the crown, which provides a circular saw. Its dimensions are divided into two groups - less than 30 mm and more than 30 mm. In the first group, the minimum value will be 14-16 mm. Manufacturers usually adhere to one initial value and apply it in all saws. The following covers almost the entire range of digital values up to 30 mm.
As for the range over 30 mm, its maximum is 150 mm. In this case, the step at the beginning of the dimensional corridor is on average 2-4 mm, and at its completion - up to 10 mm. There is also a special drill bit, available in the formats 168 and 210 mm. It is usually used for industrial purposes when equipping drilling machines. The diameter of the hexagonal shank, in turn, varies from 6.4 to 15.4 mm.
Functional support
Additional functions are more likely to relate to a power tool that drives the saw blade. Depending on the workflow, cooling and dust extraction options may be required. When working with concrete and metal, loads are excessively high, so water cooling becomes a necessity and even a safety measure. For this, drilling rigs are equipped with water tanks and its automatic feeding to the working head. Alternatively, experienced craftsmen recommend just stopping the tool at peak times. Dehumidification systems with the option of connecting an industrial vacuum cleaner are less often supplied with installations that include a wood saw, although this solution is theoretically possible. Putting a dust collector to a greater extent justifies itself when treating concrete and stone surfaces, the produced particles of which not only pollute the work site, but can also be dangerous for the operator.
Saw for wood 29588 from Kraftool
The German manufacturer Kraftool produces reliable and ergonomic circular saws. The line contains kits for different purposes, but the most popular solution is the 29588 kit. This is a circular saw set for wood, which is also used in plastics and drywall. As users note, the cutting part provides an almost perfect edge, which allows further use of blanks for point mounting works.
The kit contains crowns with diameters from 60 to 74 mm, so the kit will find application in professional construction work. Although the circular saw on wood as such does not require special reinforcement of the functional blade, the Kraftool developers made a special hardening of the teeth. Moreover, their wiring is made in such a way that the sawdust during the cutting process naturally reclines through the side slots.
Metal saw BAHCO SANDFLEX
For processing metal billets, saws are used from a special material. In particular, SANDFLEX offers bimetallic saws in 21 mm format. Such equipment allows cutting non-ferrous and ferrous metals, as well as wood. Thanks to the universal holder, the nozzle can be used in combination with hand drills and machine tools. The drilling depth in this case reaches 38 mm. Again, the drill bit was made with the expectation of self-removal of chips outside the working area. Side holes are provided for this, but depending on the model of the drill or screwdriver, it is possible to connect a separate system for removing processing products. By the way, the SANDFLEX offer is one of the most profitable in the segment at a cost - typical nozzles of common formats are available for 300-400 rubles.
HYCON HRS Concrete Saw
Equipment for working with concrete also has its own characteristics. They are clearly expressed in the design of the saw, marketed by HYCON. This is not just a circular saw, but a hydraulic ring cutter, which can also be used to form holes in reinforced concrete, brick and stone slabs. Such high technical and operational capabilities are due to the fact that diamond spraying is used in the nozzles. According to its characteristics, this saw belongs to a special segment, even within the industrial sphere. It is enough to say that only a specially trained team can operate the equipment. To ensure safety, the circular saw in the HRS modification is complemented by automatic shutdown. This function works when stuck in a solid-state niche, which also happens when using units of this type.
Terms of Use
First of all, the user must choose a suitable power base for the use of equipment. As already mentioned, this can be a drill, a puncher, or even a machine. Next, the optimal sawing mode and diameter are selected, if it is possible to adjust it. The process of making holes should be carried out without excessive pressure. It is important to feel the cutting pace set by the equipment motor. Otherwise, the circular saw may be deformed or even lead to malfunctions in the technical stuffing of the tool. After completion of the work, the processing product should be removed from the crown niche, after which the integrity of the saw teeth and the condition of the power unit should be checked.
How to sharpen a hole saw on a tree?
Due to the design features, the process of sharpening such saws is quite difficult to perform at home without special equipment. If you have the proper experience, you can use the traditional method of manual grooving. To do this, it is necessary to securely fix the equipment and, in accordance with the requirements for the condition of the teeth with a file or other hard abrasive, refine their geometry. If a standard set of crowns for wood from metal canvases is used, then this operation will not cause special problems. However, bimetallic and diamond crowns for solid materials are machined only in factory lines or on specially equipped construction sites.
Conclusion
Saws of the ring type have many variations and structural designs. In the selection, the principal criterion will be the structure and material of the fabric. In particular, the set of circular saws for wood is notable for its adjustment and flexibility. Kits for working with metal workpieces and concrete structures are more like crowns for perforators. The next step in the selection will be the specific size. It is important to consider that the final diameter of the hole may be several millimeters larger than planned, therefore, in some cases, when performing spot processing, you should initially choose nozzles with a smaller size relative to the expected. In terms of the quality of the material, there may also be different nuances of choice, but in this part it is also based on the possibility of destroying the structure of the target base. For wood and plastic, standard metal canvases will suffice, and concrete structures can succumb only to diamond solid elements.