Step 3: ROUTING THE BODY AND CAVITIES
MAKE YOUR OWN BODY BLANK Another neat trick to create your own body blank for $10 is to get a 3/4" thick peice of Birch Plywood that comes cut into a 4' by 2' board. Simply cut out two rectangular sections of the board that will accomodate your desing and wood glue them together. Be generous with the glue to make sure there aren't any spaces between the boards when you press the two together, clamp and stack weights on top of it so the two peices are joined firmly and let dry overnight. This gives you a a 1 1/2" thick body blank that is rigid and works great for electric guitars. You will have to go with a solid color paint when you finish it but you won't be able to tell the difference between it and the solid wood blank. Plus you'll save a good chunk of change that you can use towards good pickups and hardware. If you want to make the body a little thicker, you can get a 1/4" peice of birch and glue it between the two thicker peices. It's also a good idea to prerout any wire cavities in that 1/4" peice before you glue them together. That way you don't have to worry about drilling them later and ruining the top of your guitar body with the drill.
MAKING A TEMPLATE Once you have traced out your design to the wood you can start routing. I recomend making a template first for the body rout out of 1/4" hard board or something equivalent to that. The professionals use cnc machines to carve and rout the bodies but smaller shops will use templates made from acrylic. The hard board works just fine, but might not last as long. You can also rout the body by hand and forget the template but if you mess up there's no going back so be carefull if you do.
I cut my template with a jig saw and a fine tooth blade to make sure it kept a straight edge. Then i mounted it to the body blank using small screws in the ares that would be routed out later like the neck cavity area and where the pick ups would be. You will want to start routing a bit outside your line or the edge of the template so you can get you router bit to the depth it will need to be at for the ball bearing to follow the template. I use a 1/2"x1" bit with a ball bearing guide on top.I make several passes around the body, lowering the router 1/4" at a time for smooth easy cuts. Once you have made your pass were the bearing runs along side the template, it is much easier to rout and you will end up with a nice squared edge to the body.
ROUTING THE EDGE I like to use a 1/2" round over bit on the edge of the body to give it a nice even curve. You dont have to do this butit is good to round the edges of the body a little bit at least. It's easier to polish the body after you gloss it and you don't risk burning through on those sharp edges.
THE NECK POCKET The next step is to rout the neck pocket and body cavities. For the neck pocket I like to use a 1/4" bit and leave the scrap wood edge around the body to give the router the extra support it needs when routing the neck area. To find out how deep you will have to rout the pocket measure the total thickness of the heal of the neck. Then measure the hieght of the bridge from the bottom to the top of the groove the string will sit in on the saddle and add about 1/8" to it. That allows for the string clearence over the frets. The subtract that from the overall thickness that you came up with when you measured the heal of the neck. That will give you a pretty accurate depth that you will need to carve the pocket down to. Be very careful when you rout the neck pocket! You don't want to make it too big otherwise you end up with gaps between the neck and the body and you don't want to go too deep because it can be impossible to fix. Rout a little bit at a time, and set the neck in each time to make sure you get the proper fit. It shouldn't fit to tight and the pocket should be slightly lager than the heal of the neck because you will have paint accumulation in it which will shrink it a little.
PICKUP CAVITIES Same basic thing here. Be careful routing as you don't want to go outside you lines. The pickup rings tend to be thin along the outter edge, so if you go outside you lines it will look like there is a hole in the body of the guitar once you fit the rings on. Determine the depth that you will need for the pickups you are using. This is usually based on the length of the mounting screws. You will need enough room for them to fit. I use a 1/4" bit for this as well. You can use a template if you want but I do it free hand because any imperfections will be covered by the pickup rings.
THE CONTROL CAVITY Routing the control cavity is just as important as the neck pocket but with a couple more steps. The best thing to do is to cut out the plastic cover. Trace the pattern that you came up with for it on the plastic then cut it out with a jig saw. Use a fine tooth blade to prevent the plastic from chipping and will also yeild a smoother cut. Once this is done, take your template and reverse it, trace the patern on the back side of the body. Next set your router to a depth that is the same as the thickness of the plastic plate and rout the cavity working out to the line you drew. I do this free hand since the first cut is too shallow for a template. Be careful when you do this and test fit the plate you cut to make sure you get a goo fit. Then you will draw another line about 1/4" along the inside of the cavity you routed out, leaving extra room in areas for the screws you will use later on to secure the control plate. Rout this area out in the same way, working out to the line you drew. When you start to get close to the half way point in the wood start to think about how much wood you need to leave at the bottom. Usualy 1/4" is good but make sure you are careful! I miscalculated once and ended up going all the way through the body. Bad experience.