This is part 3 of my 3-string headstock design and build project.
Well, now I have a block of wood about 5.5" long by 2.25" wide by 0.75" deep with which to build my headstock. It also has a 22 degree angle cut for where the head piece will mate with the neck. The headstock diagram I drew will soon be used to shape the headstock and to drill out the 3 holes for the tuning machines (tuners). Before starting this work, let's look and talk about the headstock diagram in more detail.
From the diagram above, you can see that I have centered the three strings with the mid-line of the neck and headstock. The two outer strings are spaced 1/2" on either side of the center string, which is a fairly common string spacing for a cigar box guitar (CBG). With a 1.25" wide neck, minus 1" for the strings, this will leave 0.25", or about 1/8" between the outer strings and the edge of the neck. If you are planning to use fret wire for frets (or some other fretting scheme that crosses the entire width of the neck), then this spacing should work fine. I am planning to use industrial sized staples (click here for that article
) which are 1.125" wide, and I want a bit more room between the string and the edge of the staple-frets, so I have decided on a 3/8" spacing between stings. This will leave about 3/16" between each outer string and the edge of the neck.
With the string spacing decided, I extended the lines for the strings up my headstock so I'd know at least one side of the two angles for placing the tuners on the headstock. The other angle is formed by a line through the three tuner posts that will extend through the 3 holes we'll need to drill in the headstock. You can see this gray line on my diagram which passes through the three tuner holes highlighted in yellow. Notice that the line of tuner holes must parallel the edge of the headstock so the tuners can be mounted on that edge of the headstock. So, this angle pretty much dictates what angle I should use when cutting the left-hand side of the headstock. If you want a narrower string placement, then you'll need to increase the slope of this angle, and if you want a wider string placement, you'll need to decrease the slope of this angle.
The right side of the headstock (as viewed in the diagram) is not important, so I left it straight. The same is true of the top edge of the headstock. On my diagram, I show an "artistic" angle sloped upward at about 30 degrees. In practice, I left out this cut and just rounded off the corners. The other main differences in the piece I cut compared to the diagram above are the two angle cuts on the bottom sloping edge of the headstock. Instead of doing the "artistic" 2-cuts per angle shown on the diagram in black, I made a single cut as shown by the two gray lines, taking the shortest / easiest route.
The tuner holes should be about 1.25" to 1.5" apart. I split the distance and placed then 1 & 3/8" apart. This dimension, was in fact dictated to me, since the tuners I originally planed to use were the 3-in-1 kind where their is a single plate to be mounted that includes 3 geared tuners (as you'd find on a "3 x 3" six stringed guitar).In fact, my tuners are for a "3 x 3" six stringed guitar. The other 3-in-1 set of tuners I'll probably use, but will likely have to flip the headstock design around so the knobs of the tuner are on the right (or if holding it guitar style, the lower edge) of the headstock. I have heard (and seen) that the proper orientation of a geared tuner must be so that the round toothed gear sits below the worm gear (and post of the tuner) and closer to the neck. I'm not sure it this is an actual "must", or if it is just another old luthier's tale.
Okay, so why did I decide on a different set of tuners for my headstock? Well after building the headstock and drilling the holes for the tuners, I placed the 3-in-1 tuner in place and found that the holes on the tuning post (that the strings go come through to attach to the tuner) were not visible. My headstock was 3/4" thick and the Chinese made 3-in-1 tuners assumed the headstock would be about 1/2" thick. Well, luckily I had gone to a guitar shop a few days earlier and bought several sets of individual geared tuners. These tuners have two holes, one set higher on the tuner post than the other. These fit my headstock just fine, so now I plan to use them instead of the Chinese made 3-in-1 tuners. The lesson learned is to measure the height of the hole in the tuner posts relative it the mounting bracket to see if it will fit given the thickness of your headstock.
Well, I'm getting ahead of myself here. One of the purposes of having a drawing / diagram of your headstock is so that you can print it out in full scale and use it to position the tuner holes on your headstock. Well, the way I did this was to draw the headstock using MS Paint. After saving my headstock diagram, I printed it using the Windows "Preview" utility that you can activate by right clicking on the image file's icon on the desktop. If you use MS Paint to print, it will wastefully print it on 4 pages which you'll have to cur and tape together. After so many versions of Windows and MS Paint still has this "feature". Yuk. Well, I printed it out and it turned out too small. So, by a process of trial and error, I used the Windows "Preview" utility to zoom in a bit, then did a screen capture (Ctrl-Alt-Print Screen) and saved the image using MS Paint. With MS Paint, I'd edit out all the screen image except for the enlarged headstock diagram, and then re-save it. I would then leave MS Paint and use Windows "Preview" to print it again. After 4 attempts, I got it right. I then cut out the headstock piece of the diagram and used it as a template to place the holes for the tuners. I then used a sharp nail to punch through the paper of the diagram and mark the wood where it would need to be drilled. I then drilled out the three holes using a succession of larger drill bits until the tuners could fit. I did have to ream-out the holes a bit to make the 3x1 tuner fit (before realizing the holes weren't visible).
To mount the tuners, you will likely need a 3/8" counter sink drill bit so you can widen the hole for the do-ma-jiggy metal piece on the other side from the geared tuner to fit. I need to see what these things
are called. So re-write and expand upon this here. Should also drill guide holes for the mounting screws.Problems with my build?
1.) I used a hand drill instead of drill press, so my holes for the three tuner posts are not lined up or cut as straight through the wood as they could have been with better tools.
2.) One tuner hole cut through a dowel, which may compromise the strength of the center-line joint of my headstock. If I do it again, I'll plan my dowel placement so the avoid the tuner holes. Alternatively, I make life simpler and start with a double-width board for my headstock, rather than building from 2 half-size pieces. This way, the grains will match.
3.) The angle of the cut for the right (or top) side of the headstock cut through the same dowel described above, making that side a bit uglier than I had originally intended.Still a work in progress...
Was messing with the neck, trying to see how to fret it. I had thought the staple route might be easiest. That route was to use electrical staples 1.125" wide, and I bought some at Home Depot, but now that I sit down with them, I wonder how that guy was able to cut the side prongs down to say 1/4". That stuff is pretty stout stainless steel. He must have a real machine shop. My little nippers and files are probably not up to the job. In addition, the stapes are nearly as wide as my neck. I could slot either side of the neck and make them fit. [Hmm... that's an idea. I could put a string on either side of the neck. No, that would only complicate the playing of the instrument.] For now, I'll forget the idea of using the staples. I'll do it next time I have a 1.5" or wider neck, maybe for a 5-string banjo or a 6-sting guitar project.
Instead, I think I just have to come to terms with my fears of fretting a neck using standard fret wire and my finest saw. I'm sure I'll screw things up along the way, but the longer I put it off, the longer it will be until I perfect a professional looking fixed fret technique. I've tried a couple frets just for practice on scrap wood and it seems to work with the tools I have. So, I'll give it a go. That will probably be a week away as I have to take my wife, daughter, and her cousin Disneyland during the remainder of this week. (July 6th, 2010).
In the mean time, I think it's time to stain and then varnish the neck and headstock. I've been sanding on the neck and have got it pretty smooth, and the corners comfortably rounded. I've got a small can of pecan wood stain and a can of polyurethane. A couple coats of each should probably do the trick. I can start the staining today and finish with the varnishing when I get back from SoCal. After that, I'll be ready to add the frets, then join the head and neck.
I also need to be thinking about how to join the round cookie tin to the neck. I plan to have the neck pierce the cookie tin in two places so when I terminate the strings on the "tail end" of the neck, the string tension won't be carried by the cookie tin. I have also seen that some builders whittle away an area of the neck just under the "drum head" so that that surface will be more "free" to vibrate. I will also need to be thinking about what to use as a bridge. Since this is my first build for a 3-stringer, I'm taking my time with it, thinking through all the alternatives and documenting the process as best I can so I can replicate and improve upon my work in the future, and to share with you all my experience.