The optimal combination for your sign
The work and knowledge that goes into the manufacturing for a sign is as unique as the artistic design itself. There is a combination of elements that must be considered to prepare the final products from cutting speeds in order to optimize the finish, to the type of material used, to the kind of router bit to give the appropriate aesthetic dynamics. Although many factors can determine the finished look of a sign, these are the three that this article will touch on.
When considering cutting speeds, it can be wrongfully assumed that cutting material at different speeds will yield the same results. The speed of the blade (measured in rotations per minute, rpm) works in conjunction with the rate at which the material is fed through, otherwise known as the feed rate. It is also important to note that different materials should be treated uniquely when it comes to speed and feed rates. In order to achieve the best surface finish, reduce the feed rate while keeping the blade speed high hence reducing the chipload. Be careful not to slow the feed rate too much as this will cause the tools to start rubbing and wear sooner.
The material that is chosen for a sign is picked for durability, design-ability, and the overall desired aesthetic style. Once a material is picked, it is important to know the optimal ways of using a CNC cutter to get the appropriate finish. For metal, generally a CNC mill is used because it has immense power, but a slightly slower blade. For woodworking (or generally weaker material such as plastic or acrylic), a CNC router is the best option because it has faster blade speed while allowing some flexibility.
Lastly, the kinds of bits that can be utilized in sign manufacturing are countless. The profile in conjunction with the orientation will change the final look and smoothness of the cut. While downward bits can leave a cleaner finish, debris or other chips can build up in the work area. To avoid this, downward bits are best used on shallow cuts, and with a slower feed rate. Oppositely, upward bits can be used for deeper grooves and doesn’t have as large of an issue with chip buildup. However, it does not leave as smooth of a cut. The profile of the bit is chosen depending on the dimension and design of the sign. For example, an Ogee Bit can create an s-shape on the edge of a stock, while a chamfer bit creates a 45-degree angled cut on the square edge of a piece of stock.
So no matter how big or small, intricate or simple, the proper combination of elements from a CNC cutting machine can change a plain piece of wood or metal into a masterpiece.