Unless you are using a CNC machine, after cutting the initial rough shape of the body neck or head there is just the beginning of the journey till the finished instrument.
There are tools carve holes and shapes, tools to reshape, to round and smooth. Some of the technics and tools are interchangeable and are a matter of personal preference and some are a must.
Router is one of favorite shaping tools. It has a variety of bits and sizes and performs some of the most significant tasks when shaping the guitar body and neck. From forming the shape with a template, rounding the edges to creating the pickup cavities and forming the neck. There is a bit or more to aid us.
Good quality bits are pricy and although they are surely worth it in the long run, it really depends on how much you really use them. My strategy is to get a cheap version, or a set, and after trying out a few times, decide which are the ones I will be using and invest in the good ones. Trust me, you will know. If you do have the budget, by all means, don’t bother with the cheaper ones.
It also takes some trial and error to get the hang of routing, so it’s a good strategy to try every new bit on some scrap wood and not on the guitar itself. When damage happens with a router, they happen fast.
A basic Bit Set
A simple bit set will give you a nice range of bit to get started. It will usually include variation of ‘chamfer’ bits, some ‘Straight Carbide Tipped’ or not so straight ones and a Flush Trim Bit. These may be fine for many routing tasks and will also give you a sense of which you will want to upgrade or change.
Flush Trim Bit (Template copier)
This one is a must if you plan to work with templates. Mimicking a line and carving it into another piece of wood is made easy with this bit. Some have the bearing wheel on the top, some on the bottom and some have both. To oversimplify its work, you just press it to the template and follow along the edge. They also come in different length and diameter and you need to make sure the match your router as well as the hardness of the wood you are working with. You will often get a cleaner result by doing two or three passes and going deeper every time instead of trying the full depth in one pass. If your router is not very strong and you are using a hard wood, this is a must.
‘Chamfer’ or ‘Round-over’ Bits
Another basic bit. It will evenly and consistently round (or other profiles) your edge. They come in different radiuses and the size will be grow accordingly. The chamfers have a bearing at the bottom side so they can just glide along the edge. Make sure the edge is smooth before starting. Working on a table will give you better results vs. handheld as wobbles can happen and create dents on the edge (a matter of experience as well as strength in relation to your routers weight and balance). You do need to consider the direction of the grain as well, but that is a subject for an article by itself.
‘Straight Carbide Tipped’
you are more comfortable and want to start manually carving cavities such parts as pickups, neck slots or other more creative, non-round holes, a straight carbide tip is the bit to use. It will literally eat up whatever it touches. They come in different diameters and depths, although the depth is usually adjustable. These work best (and more safely) with a ‘Plunge’ style router and it is good practice to always pre-drill a hole large enough to plunge into instead of the wood.
Some bits may not have been designated for guitar building but maybe a good fit. This bit for instance may totally solve (if you find the right dimensions) or at least give you a very good head start when shaping the back of the neck..
Another bit worth playing around with is the Finger Board Radiusing Router Bit
This one should give you a perfect radius (or half a radius) and save you a lot of sanding. It comes in all standard radiuses, from 7.25″ to 16″ and has a 1/2″ shank. There is a whole set for just 100$.
Other than standard drill bits, there are a couple you may need which are not found in your average toolbox and are not specific to guitar building but to specific tasks you will probably come across.
A very long, thin wood drill bit
In most styles of electric guitars, you may find you need to have wires running from one are of the guitar and often there are no cavities or covers and the only way is going through the body. A handheld drill with a long bit. At just the right angle will usually be the solution.
A self-feeding, drill bit
Whenever you need to hollow out a part of a solid body or make a large round hole. Also, useful to make a ‘pilot’ hole/s for the router when creating cavities. If there is a large cavity to create (the strat style area of the pickups and switches), you would prefer to eat as much as possible with the drill and then do the clean-up and edges with the router. The cheaper ones will do the same job, as well as the spade bits, but will tend to rip the edges.
Grinding, Planing, filing and sanding
From very rough to mirror smooth, there is a list of traditional and less traditional tools to accomplish any part of Lutherie
When rough is not enough and you really want to take a serious layer/ chunk of wood of, this disc will do it, and do it fast. Mount it on an angle grinder (not very intuitive to Lutherie) and carefully remove as much as needed. Probably more useful for outlandish shapes and designs. Personally, I would prefer an orbital sander with a 40 or 60-grit paper. It would take a couple of minutes more, but the result will not be as rough and it’s much more forgiving.
Hook and Loop Sanding Discs
For lower to medium grits I like using the orbital sander and even if sanding manually I use the same paper. I try and find packs that have a variety between 40 to 800 grit, and then just refill as needed. Most Orbital Sanders will need an 8 hole 5” disc (the holes are important for collecting and clearing the dust), but make sure it matches your model.
Depending on how hard a wood you are using and the sort of finish you are going for there are a few options for manual sanding.
My personal favorites for all-around sanding are sanding sponges. They come in packs of 500- 2000 grit, they don’t rip and bend like paper and are more comfortable to work with, especially on non-flat surfaces. There are a few variations and types of sponges, but I find these the most comfortable to work with, wet or dry.
Radius Sanding Block
When it comes to the neck and the fretboard in particular a radius sanding block is a must. Depending on the style of guitar, the curvature of the neck will vary and you should get the one/ ones that match. You never want to use a straight block for a curved fretboard. The radius will range from 7.25 (common with old fenders) up to 16” (loved by modern shredders). Most of them are wooden with the radius stamped on them and come in a length of 8”-20”. The longer they are, the most consistent the sanding will be but the less comfortable id will be for more localized sanding. There are also some high-end (StewMac) Aluminum Blocks