This tutorial will walk you through the process of modeling a flawless straight-radius fretboard in Fusion 360, but the design principles can be used in any CAD environment and even applied to your hand-built fretboards.
There are three parts to this process – base sketch, extrusions & radius sketches, and the fret cuts. The walkthrough is made so that absolute beginners can follow along as well, so the sketching phase may seem a little tedious to some of you. If you happen to know a shortcut or see room for improvement in the process, feel free to email any suggestions here!
Feb 08, 2019 I'm in the process to start my first neck build and been thinking about my options for cutting fret slots. I don't have a fret hand saw like many here use with a jig, but I do have access to a CNC machine. They can scribe all the frets on the board for me, which is already a big step forward in accuracy, but their engraving bit cuts V-slots so. Game hand cutting fret slots variety is a big plus on the Internet side of things. Here, the state government of the micronation ran the casino itself, and Blanc was right at the center. It does not represent the views of Eleven Warriors unless otherwise noted. Milling Fret Slots on an Undersized CNC Machine - Part 3 by curtisa is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. You are free to: Share — copy and redistribute the material in any medium or format.
This tutorial makes use of our fretboard distance calculator, but there’s a few more options out there (especially if you’re wanting to work in Metric instead of Imperial units). We are using example fret wire measurements from Steward MacDonald.
I’d encourage anyone with the desire to learn more about the technical aspects of your instrument to get yourself a trial version of Fusion 360 (which is indefinite for hobbyists) and try modeling one. Even if you don’t intend on using it.
CAD from a Hand-Builder’s Perspective
Contrary to the common train of thought regarding automated machining as being a talentless, lazy method of guitar making, I have found the opposite is true. Being deprived of the wood, hands, intuition, and a straightedge forces you to strip the process down to its bare math. It takes me far longer to make a model of a guitar neck than with a block of wood and a rasp.
Since undertaking a quest to master modeling perfect guitars for CNC machining, I can say I know more now about the mathematic principles and design considerations that go into making a guitar than ever before.
Get Your Fretboard Measurements First
We will use a 25.5″ scale / 9.5″ radius for our example, but feel free to adjust those specs to your liking if you’re following along. You’ll want to know the following set of numbers before beginning your model:
Before we begin, we need our measurements. The scale length and fretboard radius is just a matter of preference really – this tutorial only deals with straight-radius fretboards though. If you’re making a guitar with one of our free templates, the nut width can be measured after printing or in a program like Adobe Illustrator.
The bridge width will depend on whatever hardware you’re choosing for the guitar. If you don’t have the bridge in hand to measure just yet, the manufacturers will usually include precise diagrams and/or measurements on their websites.
Bridge Height, String Clearance, and Fretboard Thickness
When you’re making a guitar by hand, you don’t have to have all your math down on paper from the start, but you should know exactly which bridge you’re going to be using beforehand. This way, you can assure that you’ll have a perfectly flat plane between the nut and saddles.
It’s no different for CAD designs – you want to know that you’ll have string clearance and play in the action before you commit.
Considerations should be made for your bridge’s adjustment heights before you route a neck pocket, pitch the neck, or thickness a fretboard. The bridge’s base height will dictate a lot of things along the scale length regarding string clearance, and is best used as a starting point for planning the rest of your guitar.
It sounds like a lot of measuring and figuring, but if you take a look at the first diagram in this article (this one), you’ll see that you can check clearance by dry fitting the parts and placing a straightedge on the fretboard and extending a line out to the bridge saddles. When in doubt, make your fretboard thicker and plan to shave some off of the bottom with a belt sander to get the height right when test-fitting it.
How to Model a Perfect Fretboard (Straight Radius version)
Click the images in the galleries below and cycle through with your arrow keys.
There you have it – a perfect straight-radius fretboard with perfect slotting. The CAM process is going to come down to your own equipment and preferences, so the process for creating toolpaths has not been included here.
I was looking for an easier way of cutting multiscale fretboards and this is what I came up with. I'm happy with the performance of this little jig and, having not seen anything of the like before, thought I'd post it up here hoping some others may get use from it.I know many of you are using the tablesaw/fret template method to cut slots in your fingerboards however there are always times when odd scale lengths arise for which you don't have the template; the template does not exist or the expense can not be justified for the one job. Also, as previously mentioned, this does a great job of cutting the slots on a Multiscale guitar which I don't think there is a method of doing easily by tablesaw; so it is of use to any luthier I would think.
I personally also don't have the tablesaw set up for such jobs so for me it was necessary
So here it is, sorry for the poor photo quality - had some trouble uploading higher res images. The labels in the first pic are not because I think you couldn't work this out yourself, but that I refer to them later.
So that's it. A base, fence, two hold downs and a pivoting magnetic guide - pretty basic but works well. I have been using versions of this jig for years but this is the most versatile currently. The hold down clamps (I love these things for jig making) are close enough to the saw as to provide secure clamp force, while far enough not to interfere with the cutting action. Here is another shot showing clearance for up to an 8mm thick fretboard under the guide. Also note the routed section to provide clearance for the cut at any required angle and the two countersunk magnets to guide the saw.
The pivoting guide is locked by an allen key bolt. This clamps up surprisingly firmly with little to no movement under tests with decent hand pressure applied to the end of the guide. Remember too - this is only a guide; the actual sideways force when in use with the saw would be far less than the tests applied. In any case, it has not moved in use at all. In this next picture (left) you can see the base contains a 'captured' nut. The fence mounts on top of this to secure it and to provide a more even clamping pressure, I have rebated an area for a washer under the fence to sit flush against the nut - as shown on the right.
The fence now gets screwed down to the base. The guide is made from a scrap piece of rock maple I had around. The bolt is drilled through the end and the hole is countersunk providing enough room for another washer on this side, while the entire head is below surface level so there is nothing to get in the way. Two rare-earth magnets are countersunk to provide firm attachment and guiding of the saw, yet allow enough movement to be a smooth cut. Something like silverglide could be used if you like to really free up the cutting action. So now it's ready to use on the current project.
The clearance under the guide is important as the more room you give, the harder to line up accurately it will be. I usually use a 7mm thick board to start with so there is just enough clearance to move things around but easy to line up. The length of the guide is long enough to cover the fret board but not too long exacerbating the risk of movement. Action shots - a few slots done.
Note Hesh - erm of course I'd normally attach my shop vac to the erm, saw blade, but um, photo clarity and all that you know?
Finally, there is nothing worse than not being able to find the right size key when you need it. Hence I simply drilled and rebated a slot in the fence to hold this one by magnet. It always goes back there when I'm done - in use it sits in the guide itself as a 1/4 turn is enough to loosen then re-lock it for the next fret.
Cutting Fret Slots By Hand Crossword
The end result on this particular multiscale fretboard.That's it. I hope it's of some use. If anyone can think of any improvements or other ways of cutting fanned frets, I'd love to hear it. I'm still trying to get my head around designing a mitre system that can take two fret slot templates... The beauty of this jig too is that there is no reason you couldn't add a pin to accept the fretting templates, though you would have to design it with this in mind and compensate. Also, you can cut fret slots on a single scale length guitar who's fretboard is already tapered or not square. Simply run the fretboard against the fence and set the guide to the required angle. All the slots can then be cut without changing the guide. Probably others will now point me to where this jig already exists and could have saved me the trouble of dreaming it up...
Cheers,
Cutting Fret Slots By Hand For Sale
Cutting Fret Slots By Hand
