Guide written by:
Michael, Professional and passionate welder, Sheffield
Rotary disk cutters, circular saws, metal band saws and angle grinders: these are tools made to produce perfect metal sections! Either on a frame or portable, for the workshop or the construction site, each distinctive cut has its corresponding metal cutting machine! Say goodbye to the hacksaw and hello to modern tools!
- On frame
- Circular saws
- Metal band saws
- Angle grinder
- Cutting depth
What is a metal cutting machine?
In the past, this massive workshop tool was often of Italian or German origin, composed of an enormous blade lubricated with soluble oil and featuring an automatic feed system with adjustable settings. These features allow the user tocut an extensive amount of sections. The professional tasked with supplying the metal and adjusting the length basically only has to monitor that the operation is going smoothly!
Several machines can easily work together at the same time. Another option to cut steel is the gigantic band saw which is a crucial addition to the ever expanding fleet of machines. These imposing cutting machines have however begun to be replaced with more compact, faster and less expensive alternatives. Progress! It can only make the tools we use even better!
Workshop machine vs on-site?
Whether you need to cut metal in the workshop or on site, you have the choice between a fixed and portable saws or cutting machines.
Workshop metal cutting machine
For frequent and intensive workshop use:
- A 350 mm disc cutter on a frame;
- A rotary disc cutter/milling cutter;
- The metal band saw on a frame.
Onsite metal cutting machine
For frequent and intensive use on site:
- A portabledisc cutter- with up to 350mm disc;
- A portable metal band saw;
- A 115, 125 or 230mm grinder.
For a versatile use that can be both intensive or occasional on constructions sites, the angle grinder (with 115 or 230 mm diameter) is the perfect tool to cut metals and different materials (various discs, fast assembly) with ease and speed.
Metal band saw
Metal cutting machine on frame: definition
The metal cutting machine, when fitted on a frame, is only suitable for the workshop. It can produce both perfect straight cuts and angled cuts, no matter what the angle, thanks to its pivoting seat and graduated resistance, segmented in specific degrees.
On top of the trigger control, the machine's controls consist of a progressive start switch and an emergency "punch" button for any unexpected developments.
The primary part of this tool is an abrasive 350 mm wide disc. This consumable part is composed of a conglomerate ofcorundum (a mineral almost as hard as diamond) and emery as well as other components that are glued on a covered surface that limits the projection of particles - especially if the disk ever accidentally burst. As its primary responsibility is to wear itself down during the cutting process, the disk should be replaced when it is used to the point of no longer being capable of cuting a section in one go (average thickness of 2 to 4 mm).
A metal cutting machine's rotational speed is generally around 3,800 rpm. Using this machine produces enormous sparks and particle spatters that must be directed towards a safe surface, such as a sheet of steel, to limit the risk of fire. On top of the disk's dimensions, which should be clearly labeled on the disk itself, the applicable standard, its rotation speed,its granulometry and the product manual should also be visible.
The main factors to look out for are the machine's cutting capacity and its power, expressed in watts.
The ultimate configuration is a laser sight, which greatly increases the precise nature of the cut. It is advisable to add one or two trolleys, a type of trestle composed of a straight or V-shaped frame on which the section are laid to support them as they go into the metal cutting machine.
What about the rotary disk cutter?
Designed for the workshop, itconsists of aframe on which is positioned a disc cutter, with safety controls and gear shift.
Its vice features a quick tightening function. The machine's base or head can pivot to achieve angled cuts ranging from 0° to 45°.
Generally sold in the 400V range, the power can vary, from 1,800 to2,500W - the stronger the disk cutter, the more easily it will be able to cut large sections.
Its disk, equipped with tungsten carbide teeth, is lubricated with soluble oil through a pump - often set in the frame, which also has room for tools and spare parts. The disc is protected by a removable cover to allow for its replacement.
Lowering the cutting mechanism is done manually by means of a lever placed at the top of the machine.
An adjustabledepth setting is normally also standardly present on machines to facilitate repetitive cuts. The machine has the advantage due to its cutting speed and cleanliness (no burrs).
Metal band saw: workshop and portable
Band saws are also divided into two categories: workshop and portable.
Fixed metal band saw
A fixed metal band saw is a machine that is installed on a frame, to work at an elevated hieght. Equipped with a vise and a progressive lowering system via an adjustablecylinder, the band saw can produce angled cuts. Its increased cutting width is one of its strong points. The blade can also be lubricated to achieve clear and precise cuts.
Portable metal band saw
A portable metal band saw allows you to work directly on the surface that needs cutting. Battery powered, handy and lightweight, It's not uncommon to see auto body workers using them to cut out car cabs!
What is a disk cutter?
It is by far the most commonly used model as it is available in both portable or fixed variations.
Fixed disc cutterThe fixed disc cutter is composed of a base on which the disc cutter is mounted on which is lowered via a handle onto whatever needs to be cut. It features a progressive ignition, around 2,200 W of power, 2,200-4000 rpm, and a 350mm wide disc - for a cutting depth ranging between 115 and 140 mm. The base is equipped with a vice - purely for maintenance - and can be fixed on a worktop. Depending on the model, they will have a more or less elaborate protective housing, which shelters the user from any projectiles during the cutting.
Mobile disc cutterA mobile disc cutter looks exactly like a grinder. Its technical characteristics are identical to the fixed model except that it has several different disk diameters at it's disposition (125, 180, 230, 355mm) and its power and rpm can vary. Some models may have rolling housings and be connected to a vacuum cleaner. When making your final choice, remember that for a disc cutter, the more powerful it is and the more rpms it produces, the easier it will cutting through materials - provided you have a high-quality disc of course!
Angle grinder: use and features
An angle grinder with a 115, 125 or 230 mm diameter cutting disc is very often used on the job site because it is versatile, light and powerful .
This machine, available in 220/230V and featuring anywhere from 1,400 to2,200W of power, uses disks whose defined use is precisely defined, and must not be used in any other fashion. Its low weight and maneuverability make it an indispensable tool.
Any finishing touches or difficult access to the surface is generally ensured by a 125 mm grinder while largescalecuts is the role of the 230 mm model. These grinders can also be pneumatic.
A angle grinder's average air consumption varies and is based to the disk's diameter. The use of a compressor with a steady flow, that is capable of supplying the pneumatic grinder while leaving a marge of security is required unless you want your machine to stall in the middle of a cut!
Final tips for use
The use of the metal cutting machines described above requires an increased level of focus and concentration.
Always try to anticipate what might happen. Can you make out where the piece will fall once it is cut before you start?
Use trestles and trolleys to simplify the task.
For passionate hobbyists, DIY lovers and heavy duty professionals looking for the right equipment, follow the links below for cutting-related accessories, advice from our editors and more helpful guides:
- How to choose your grinder?
- How to choose your cutter?
- How to choose your bench grinder?
- How to choose your grinder accessories?
- How to choose your plasma cutter?
- How to choose your tool box?
- How to choose your lubricant, grease and oil?
- How to choose your compressor?
- How to choose your portable tools' battery?
- How to choose your portable tools' battery charger?
- How to choose your trestle?
- How to choose your vacuum cleaner?
And to work safely
Guide written by:
Michael, Professional and passionate welder, Sheffield, 70 guides
I was trained as a pipe worker and a pipe-welder and after having traveled for 35 years working around the UK, I became the head a metal shop and then a designer and in the end the head engineer. I have designed and built a workshop where I make metal sculptures: I managed to find a piece of paradise where I can to let my imagination run wild. Auctions and garage sales are no secret to me. I find unusual objects and old tools there that I collect or transform into works of art. I also like decoration, painting on canvas, and gardening. I am developing new technologies concerning tools. To share my passion and humbly advise you in your choice of materials is a real pleasure.