In short, a laser is a focussed beam of light that concentrates a lot of energy on a very small area. When this happens, the material in front of the laser burns, melts or vaporises, creating a hole. If you then add a CNC machine to the mix, you get a machine that can cut or engrave very intricate parts from wood, plastic, rubber, metal, foam or other materials.
Every material has its limits and advantages when it comes to the Laser cutting goes. For example, you might think that a Laser can cut everythingbut that is simply not the case.
Not every Material is suitable for laser cutting. This is because each material requires a certain amount of energy to be cut. For example, the energy required to cut paper is much less than the energy required to cut a 20 mm thick steel plate.
Keep this in mind when you buy a laser or order it from a laser cutting service. Always check the power of the laser or at least the materials it can cut.
As a guide, a 40 W laser can cut paper, cardboard, foam and thin plastic, while a 300 W laser can cut thin steel and thicker plastic. If you want to cut through 2 mm thick or thicker steel sheets, you will need at least 500 W.
Below we look at whether you have your own device or an Service for the laser cutting of metal and some design basics.
Your own laser cutter vs. a service
In the age of CNC machines, laser cutters that can cut metal are still too expensive for the average hobbyist. You can buy low power (less than 100W) devices quite cheaply, but these are unlikely to scratch a metal surface.
A Laser for cutting metal must have an output of at least 300 W, which will cost you up to EUR 10,000. Apart from the price, metal cutting machines also require gas - usually oxygen - for cutting.
Less powerful CNC machines for engraving or cutting wood or plastic cost between 100 and several thousand euros, depending on how powerful they need to be.
Another difficulty when purchasing a metal laser cutter is its size. Most devices that are capable of cutting metal require as much space as you can find in a workshop.
Nevertheless the laser cutting machines As laser cutting machines become cheaper and smaller, we can probably expect to see desktop laser cutters for metal in the next few years. If you are just starting out designing sheet metal, you should consider the following before buying a Laserschneider's online laser cutting services to consider. Let's take a look at a few options below!
Whatever you decide, remember that laser cutters are not toys, especially if they can cut metal. They can seriously injure you or cause serious damage to your property.
Design tips for laser cutters
As laser cutting is a 2D technology, it is very easy to prepare files. Simply draw the outline of a part you want to produce and send it to an online laser cutting service.
You can use almost any 2D vector drawing programme as long as it allows you to save your file in a format suitable for your chosen service. There are many CAD tools, including free ones, that are designed for 2D models.
To produce your first laser-cut sheet metal part, you need to do the following:
Draw an outline of the desired part in a vector drawing programme.
Save it in a suitable file format (see the list of online services and supported file types).
Upload the file to an online laser cutting service.
Check the price or ask for a quote, and if the price is right, order the part.
Wait for the delivery.
Before you order anything for laser cutting, there are a few rules you should follow. Most suppliers have some sort of guide on their website that you should follow when designing your parts, but here are some general guidelines:
1. closed contours
All cutting contours must be closed, full stop. This is the most important rule and the most logical. If a contour remains open, it will be impossible to remove the part from the raw sheet. The only exception to this rule are lines intended for engraving or etching.
2. line colours and thicknesses
This rule is different for each online service. You should check the colour and line thickness required for cutting. Some services offer laser etching or engraving in addition to cutting and may use different line colours for cutting and etching. For example, red lines could be used for cutting and blue lines for etching.
Some services do not care about line colours or line widths. Check with your chosen service before uploading your files.
3rd round holes
If you need holes with tight tolerances, it is advisable to pierce them with a laser and then drill them with a drill. When piercing, a small hole is drilled into the material, which later guides the drill bit during drilling. A pierced hole should have a diameter of around 2-3 mm, but this depends on the finished hole diameter and the material thickness. As a rule of thumb in this situation, start with the smallest possible hole (if possible, keep it as large as the material thickness) and gradually drill larger and larger holes until you reach the desired diameter.
4. holes with thread
This only makes sense for material thicknesses of at least 1.5 mm. Steel, for example, melts and vaporises when it is cut with a laser. After cooling, the cut hardens and is difficult to thread. For this reason, it is advisable to cut with a laser and drill a few holes before tapping, as explained in the previous tip.
5. round corners
Sheet metal parts can have sharp corners, but if you add fillets to each corner - at least half the material thickness - the parts will be less expensive. Even if you don't add them, some laser cutting services will add small fillets at each corner. If you need sharp corners, you should mark them as described in the service provider's guidelines.
6. notches and tabs
The minimum width of a notch must be at least 1 mm or the thickness of the material, whichever is greater. The length should not be more than five times its width. Tabs must be at least 3 mm thick or twice the thickness of the material, whichever is greater. As with notches, the length should be less than five times the width.
The distance between the notches must be at least 3 mm, while the tabs must have a minimum distance of 1 mm or the material thickness, whichever is greater.
Failure to comply with this rule can lead to deformation of the part.
7. multiple parts or thin features
If you several parts on the same tray cut, it is a good rule of thumb to leave a distance of at least the material thickness between them. If you place parts too close together or cut very thin parts, you risk burning away the material between two cut lines.
Summary
Owning your own laser cutter has many advantages. The most important thing is that you have full control over the machine. You also don't have to worry about delivery times or whether the company can handle your project. However, owning a laser cutter is not for everyone. They are expensive and take up a lot of space. If you don't have the money or space for a laser cutter, you can also use a laser cutting service.
Laser cutting services have many advantages over having your own laser cutter. The main advantage is that you don't have to worry about the cost or maintenance of the machine. You also don't have to worry about storage space or whether you have the right power source.
Another advantage of using a laser cutting service is that you can usually complete your project faster. This is because most service providers have several laser cutters and can therefore work on your project while you are busy doing something else.
Finally, many laser cutting services offer discounts for larger projects. This is because they can often cut multiple parts at the same time, saving them time and money.
When deciding whether you should use a laser cutting service or buy your own laser cutter, it all depends on your needs. If you need a lot of cuts or want to cut multiple materials, a laser cutting service is probably the best choice. However, if you only need to cut a few parts or just one type of material, then buying your own laser cutter is probably the best solution.
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