The ABC’s and XYZ’s Of Precision Sign Manufacturing
Computers have changed everything! This statement has never been truer than in modern sign manufacturing. The use of Computer Numerical Control (CNC) equipment ensures that precision is virtually guaranteed. Not to mention how efficient these newer CNC controlled machines are at cutting and shaping a wider variety of materials every year.
With the advent of digital technology so many years ago, modern sign manufacturing was quick to take advantage of the control and processing power that computers gave us. One of the more utilized tools in a sign shop is the CNC driven Router. A Router is simply a very powerful high speed motor called the Spindle. Some modern routers now turn as fast as 60,000 Rotations Per Minute (RPM). The spindle uses a variety of differently shaped bits. These router bits are designed to cut specific materials. Depending on how hard or soft the material may be and what type of cutting is involved. The spindle RPM, the bits used, the speed and depth of travel through the cut are all parameters that are controlled by the cutting software program.
The spindle is mounted to a carriage. The carriage maintains very precise control of three basic coordinates; X, which is one lateral direction (North to South) Y, the other lateral direction (East to West) and Z, (Up and Down). Using a computer program specifically designed for this purpose, the operator will program the carriage to perform a very precise sequence of tasks. Including how fast to spin the tool, In what direction to move the spindle. How fast to move through the cut, how deep to cut into the material and how many times the router bit will need to move through the same tool path if multiple cuts are required. Modern routers can even change their bits, depending on the tasks that are programmed into the cutting file.
Since we now have precise control over how deep the Router’s bits will cut on each pass, shaping material is also possible. Cutting shapes with rounded or angled faces, as is the case with a prismatic letterform, is now simply a matter of programming.
Some systems now incorporate additional tools and parameters to the basic three coordinates used in flat cutting & shaping. These additional coordinates control the rotational movement around the axis of a part that has been setup on a Router Lathe Attachment as shown here:
This enables a traditional router, typically used for 2 dimensional cutting, to now machine a fully 3 dimensional part.
Because of their flexibility, the Router Table is usually the first choice for Sign Shops. Profiles, letterforms, hole patterns, openings in sign faces for plastic to fit in and other various layers of materials that are used to build signs, are now precisely cut to ensure that parts fit together perfectly with minimal seams. Since Routers can only cut materials that are softer than the bits used in the routing process, it takes a different process to cut steel and harder materials. In Fact, cutting these harder materials requires a different process all together. Lasers, Waterjet and Plasma cutters all work from the same set of XYZ coordinates that a Router table uses. The difference lies in the tool head of these different machines.
Lasers are great for precise cutting of thin steel sheets up to ¼” in thickness and plastic sheet materials up to 1” in thickness. Some more powerful lasers can cut thicker steel plate but it takes a lot of energy to drive them and that is usually where Plasma cutters take over. Plasma is less accurate than Laser cutting but it takes much less energy to cut through thicker steel plate than a Laser would need to do the same job. Plasma is typically less accurate due to the fact that the Plasma arc itself is not as focused as the Laser’s very thin cutting stroke. The laser process is well suited for cutting the many plastic materials used in sign manufacturing. Due to the high heat involved in the cut, the edges of many of these materials, including acrylic, emerge from the cutting process with highly polished edges.
When it comes to strictly flat cutting capability, one process has emerged that truly rules them all; The CNC Waterjet machine. Using water, that is forced through a tiny orifice at extremely high pressures, a CNC driven Waterjet machine can easily cut steel and other very hard materials 2-3 inches thick. Glass, stone, and stainless steels are no match for the modern Waterjet machine. The thickness of softer materials is only limited by the upper limits and table clearances of the carriage system that holds the water jet cutting head. Typically, when cutting steel and other harder materials, powdered abrasives are mixed with the water jet stream to help cut more efficiently and accurately.
The photo below shows how precisely a Waterjet stream, mixed with abrasives, can cut through a solid block of aluminum:
Signs Plus takes full advantage of the precision offered by these CNC machines on virtually every project we build. This ensures that every element involved in your project will be exactly as designed. Taking the artwork directly off of the pages as rendered, we will scale it, convert it to language that our machines can understand and cut it. Once everything is cut, our skilled fabricators will fit together, weld and finish all the elements of your project. Our expert crews will then install it all in full compliance with the latest building & electrical codes.
Ensuring that your brand, logo and every signage element will be built and installed as precisely as it was shown in the original design. Not only that, our CNC driven equipment virtually guarantees that everything will fit together perfectly and with the highest tolerances for fit and finish available in the industry today! Call now to find out how we can apply all this awesome technology to your next project!