CNC Advantage

Using a Computer Numerical Control unit (CNC) to control the operations from a router is often seen as not “authentic”. But the same could be said of other inovations like vaccination, antibiotics, soap and democracy. We have access to tools that allow us to do a better job as long as we use them properly. So here are some of the main reason that led me to slowly migrate towards using a CNC.

• Accuracy – I can measure ten times and still be more accurate using a CNC. The thing is, once set up properly, the CNC will carry on doing the same operation to perfection every single time. And if you find a way to improve or refine a process, then the improvements can easily be implemented from the next run onwards. I can also do some virtual modeling and see how an item will look long before making the first cut.
• Blind Frets slots – Fret slots are not only in the right place time after time, but they are cut at a set depth that follows the curvature of the fingerboard, even if it is using a compound radius, making sure that the least amount of wood is removed. As a result, the frets once fitted have very little airspace underneath them which helps the integrity of the build and improves tone. Even better, I can stop cutting before the edge of the fingerboard and have the last bit of the fret tang seated in such a way as to eliminate sharp or popping fret ends. The feel is smooth and “worn in” and as the fret tang is invisible and the slot doesn’t go to the edge of the fingerboard, the slots are called “blind”. I’ll write a separate piece soon on “Fanned” or “Multiscale” fretboards, which are also much easier to achieve using a CNC.
• Compound Radius – The Fingerboards can have a variable radius, flattening out as you get up the board. This allows for better ( lower ) action as it reduces the risk of strings choking out as you bend them while playing lead in the upper register.
• Less Human Error – It is easy to underestimate how much difference applying simple pressure while hand guiding your router or workpiece makes. Using my old Pin Router I can get great results but the operator needs to know the jigs, the wood, and the machine to compensate for a lot of limitations and idiosyncrasies. I had the odd guitar body fly across the workshop too and it’s scary.
• More time for other tasks – As I am typing these words, I am currently machining 3 fingerboards blanks. There are numerous tool changes to be done and all going well, it will take roughly 3 to 4 hours to get the boards radiussed, and cut to size, inlay pockets and fret slots cut. To be fair, you could probably do it by hand ( and by that, I mean hand controlled tools using jigs etc…) much, much, faster. But the result wouldn’t be as accurate and I wouldn’t be able to multitask.