Engraving is a process that involves marking a surface without the use of paint or inks. There are many different methods of engraving, ranging from high-precision laser engraving units to the more traditional methods of hand engraving with nothing but a graver and workpiece support. It is important to know the differences between the differing methods in order to determine which is going to be the right one for you.
Different types of Engraving
Diamond drag is a process that quite literally drags a diamond over the workpiece, leaving a bright, even scratch in its path. Manual Pantograph machines were among the first pieces of machinery to employ this method, which started to become popular in the engraving trade around the 1960s in New Zealand.
Pantographs have almost completely become replaced now with CNC engraving machinery that is driven by computers and can produce extremely detailed, fast results. Diamond drag engraving is mainly used to mark metals, but can also be used to engrave directly to glass.
Deep-Cut or Rotary engraving
Deep cut engraving can be used on metal, wood and plastic, and is often performed on the same machinery as diamond-drag engraving, with a few key changes. The difference being instead of a diamond tip being pushed around on the surface of the workpiece, deep-cut engraving employs a cutting head that rotates at high speed, to carve a deep channel in its path.
Deep cut engraving is arguably the most durable form of all types of engraving, producing a deep, tactile finish that is often enhanced by paint-filling or oxidising. Stamps, molds and stencils can be manufactured using this technique, as well as heavy deep-cut brass or stainless steel plaques(click here to see our range).
Laser engraving is a process that involves firing an extremely thin beam of high-intensity light at the surface to be marked. The laser beam discharges enough power to burn or scorch the surface it hits, and is driven by computer which allows a great deal of complexity and control to be achieved. Different types of lasers can mark or even cut any material, the most common types of Co2 engraving lasers are able to engrave types of plastics, wood, and some metals.
Special types of laminated plastics are available which consist of two or sometimes three layers of differing colours. When hit with a laser beam, the top colour is burnt away which exposes the second colour underneath. Certain types of plastic laminates such as this are UV-stable to resist fading, and are made for harsh environments which enables them to be used as a cost effective method of sign or label making for industrial use.
UV Printing is relatively new in New Zealand when compared to other methods of product marking found in the industry. An Ultraviolet printer is a machine that is able to print directly onto a variety of surfaces using special inks that are cured by high intensity UV light. UV printers can print full CMYK colour up to 5760x1440dpi, and can also print clear and white ink. UV ink is very tough yet brittle, and when cured correctly will produce a relatively impermeable ‘crust’ that sits on top of the surface it has been applied to.
The ability to print onto almost any flat surface, plus the durability of UV inks means that a UV printer can be set up to perform a large number of tasks, from printing logos on promotional merchandise to manufacturing huge outdoor signs. Here at Crown we use a large UV printer to manufacture most of our namebadges, along with custom acrylic awards, printed wooden plaques and shields, aluminium plates and promotional products.
UV Printed Materials
- A custom made acrylic plaque
- Aluminium badges with a resin dome
- Colourful Ultraviolet printed badges
- Printed flexible vinyl labels
- Braille printing on stainless steel
- Full colour printed acrylic awards
- UV Printed colour acrylic awards
- Sliding Door signs are our specialty
- Colour printing on textured surfaces
- A UV printed acrylic award
- Printed wooden desk stands
Printing or Engraving
UV Printing is innovative technology that delivers fantastic results, but the biggest drawback is the fact that it relies on surface-based inks that do not ‘soak in’ to the surface that they are applied to. All forms of engraving and most other forms of printing (latex, thermal transfer, solvent, inkjet etc) rely on sub-surface methods that allows the text to be absorbed or cut down into the surface, leaving a mark that has far greater durability. UV inks are designed to do the exact opposite of this, and sit on top of the surface they are applied to. This is what allows printing on such a wide variety of substrates without experiencing issues such as bleed or feathering. Curing of the ink is achieved through use of a powerful ultra-violet LED that allows the ink to solidify into a tough, textured exterior that develops a very strong bond with the surface it has been applied to.
Once fully cured, UV ink develops into a very hard, tough media that resists minor abrasion and impact. The fact that it is cured almost immediately after coming into contact with the product surface means that layers can be built up to several millimetres, so textures and contours can be produced, as well as Braille.
Any engraved product, whether it is laser, diamond drag or deep-cut engraved, will always have one common theme – lack of colour. Engraving is a totally different method that relies on cutting, burnishing or burning the substrate in such a way to leave behind a permanent mark. This instantly rules out any form of engraving for a lot of work that requires exact colours to be matched. There are some circumstances when colours can be used in engraving, such as the use of plastic laminates. Special types of laminated plastics are available which consist of two or sometimes three layers of differing colours. When hit with a laser beam or rotating cutter, the top colour is engraved away which exposes the second colour underneath. This enables basic colours to be incorporated into labels or plaques that have an extremely high level of durability, as this is the area in which engraving excels.
Industrial labels for environments of extreme or harsh conditions, outdoor plaques or signage, and products that will resist graffit or vandalism are all ideal candidates to be engraved instead of printed.