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Rand Moore's Cigar Box Ukulele Project 2, Part 1

Posted by Rand Moore on August 10, 2010 at 1:00am
Hi All.

I completed my Cigar Box Ukulele Project 1. The instrument turned out pretty good, but because I chickened out and only put diatonic fretting on the neck, I discovered that it makes ukulele playing a lot more confusing rather than simplifying it. Perhaps, with GCEA tuning, diatonic fretting doesn't work. I know I was confused, so I re-tuned it to "D-A-d-d" and used a nut and bridge set up to support dual course melody strings spaced 1/8'' apart from each other and 3/8'' apart from "middle" string (which is 3/8'' away from the bass string). So, it ended up as a short necked stick dulcimer (strum stick) with dual course melody strings and diatonic scale. I actually like playing the instrument a lot, except a lot of song tabs also use notes off string 2 which is a single string, so it sounds "odd" switching from single string to dual coursed and back periodically thru the song. So, I'm thinking of doing a 5-string long neck string dulcimer with dual course melody and middle strings, and a single bass string. Or, maybe dual course everything, but then the melody won't stand out so much from the drone strings.

Well, I have been a bit side-lined due to frustration over my poor woodworking skills. Then I decided to read up on woodworking in general on the Internet, and one of the articles I came across was the need of a good, solid workbench. This rang a bell with me, because the table I was using as a workbench is really shaky. It was built out of junk wood collected by my father-in-law and just nailed together. So, I have modified the table so that the back side is more rigid, and have added some additional pieces so that the table fits well tightly against the front porch wood railing, so essentially I'm using part of the house to stabilize the work bench. It also now has a 26'' wide x 13'' deep x 1'' thick "marble" top, so it's a lot more steady now. I have also sacrificed some wood to use on my workbench to help me hold my work piece tightly. I have no vice, and only 2 clamps, so I have to get creative sometimes in terms of how to clamp things down and hold my workpieces steady so I can cut them accurately. The results have been pretty good, so now I am starting up another Cigar Box Ukulele project. This time a tenor cigar box uke, with a 17" scale length.

The other thing I want to build is a hardwood miter box with 15 degree and 90 degree cut angles. But, I think I'll wait and make it in China as my collection of tools, parts and instruments has grown significantly and I need to port it home in my luggage. That's in 9 days. So, I'll wind up my current Cigar Box Ukulele project (project 2) and then carefully pack everything for my return trip.

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For CBU Project 2, the neck will be an inch longer, and the bridge on the box will be moved back to about 2/3s of the way to the "tail piece". This will provide a 17'' scale length. As I recall, the string spacing is a slight bit wider on a tenor uke, but I'm planning to use 3/8'' sting spacing like on my concert uke. I feel more comfortable with that string spacing. However, I like the idea of having a longer scale as when I playing up the neck, I'll have more room for my fat fingers. On my last project, the last few fret positions get hard to play, so hopefully a longer scale length will help correct for that. A 17'' scale length is also about the same scale length as a prima balalaika, so I'm thinking that down the road a bit, I may try to make it imitate a balalaika by using balalaika sized strings and tuning. This instrument will definitely be chromatically fretted. Here's a diagram.


Notice the changes in my design of the sound box. A single large sound hole in the middle replaces two smaller ones on either side of the strings. This is made possible by doing away with the through-the-body neck. Instead, I have beefed up the side of the cigar box which will receive the head/neck assembly, which will be attached using two 2'' long #10 wood screws. What is not shown in the diagram is a 2'' heel attached to the bottom side of the neck to make this connection stronger. Here is a diagram of that.


Also notice that the bridge & tail piece has be redesigned into a single piece and is backed up on the bottom side of the sound board with another board to distribute the strain of the string tension better. I'm also thinking of mounting a pair of piezo pickups under the bridge, possibly as part of the bridge assembly. But, I have not yet decided to do it as some people say it will sound better if the piezo pickups are mounted to the soundboard away from the bridge as they will be less sensitive to other noise (I assume on the strings, like pick strike noise on the strings). So, likely I will need to do some experimenting; again, once I'm back home in China. My soldering irons, heat glue gun, etc. are over there.

Well, that's the plan for now. Have to go now.

- Rand.










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3-String Headstock Design #1, Part 2

Posted by Rand Moore on July 4, 2010 at 6:00pm
Once you have a board prepared for use as the headstock (as described in the previous post), you need to decide how you will be attaching it to the neck and how you will be installing the tuning machines (tuners).

Let's start by discussing how I plan to connect the headstock to the neck. As you may recall from the first post, my neck and neck stock both have a 22 degree cut (plus or minus a degree), revealing a sloped surface about 2 inches long. The question is how the headstock will be positioned relative to the neck for gluing. Here are the four possibilities:

Here's my first diagram, and when positioning the two pieces relative to each other. Notice how this "method" tilts the headstock down by about 20 degrees, like many guitar heads. The reasoning for doing this is based on hearsay (not first hand scientific testing), and the story goes that the strings will stay in the groves of the nut better and that the strings won't buzz at the nut. I really don't know. It's likely just an old luthier's tales. But modeling an instrument after traditional design practices are more likely to produce a better instrument. So, I'm planning for a 20-25 degree tilt in the head relative to the neck.


However, I don't really like how exposed (visible) the head-to-neck joint will be. This is better illustrated in the diagram below (circled in red). I think this placement will look ugly without doing a lot of work with wood putty, bondo, or some other "filler" to round out and sculpt the joint to make it look better. But, that may make the problem worse should I go to stain and varnish the wood. So, at this point, I'll skip this method and move on to the next possibility.


The next head-to-neck positioning possibility places the headstock over the neck, hiding most of the ugly head-to-neck joint. This is how I'm going to do mine.



Like the first method, this second method tilts the headstock downward about 20 degrees or so, like a real guitar. But, unlike the first "method", this "method" hides the ugly neck joint under the headstock, making it a lot less noticeable as shown in the diagram below (see the red circled area).



There are a couple other possibilities... but they don't provide the traditional headstock tilt found on most guitars and other lutes. I have tried this third option on a "soda can on a stick" variety canjo and it worked pretty well, especially when I did a similar cut and join on the "tail" end of the canjo stick for the "strum hollow" and the can resonator. The net effect of this canjo design was to raise the "fret board" area of the neck up closer to the strings for easier playing action. This design would also allow you to sit your canjo down and it would rest on the flat lower head an lower "tail" sections, assuming you mount your tuners so the knobs point out to the side and the gears are recessed into the headstock. Issues for another article/post, I guess. The down side of positioning option 3 is that the ugly neck joint is again starring you in the face.

Well, the fourth method doesn't make much sense, but if you had to have a flat head-to-neck layout, it could be done; and the ugly neck joint would be mostly hidden by the headstock.

Okay, now that I have decided how to connect the headstock to the neck, I going to hold off on actually attaching the two pieces until I have finished drilling holes for mounting the tuners in the headstock, and until after I add frets to the neck. Adding frets with a 20 degree downward tilt in the neck is more difficult unless you've build some kind of "rig" to hold the neck steady without putting pressure on the headstock.

[As a note, when I do glue to two pieces together, I also will screw them together using a short wood screw. Want to mention that now in case I forget mentioning it later. The screw hole comes through the bottom of the neck through the headstock where the two pieces join along their sloped sides.]









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Rand Moore Cigar Box Ukulele Project 1, Part 3

Posted by Rand Moore on July 27, 2010 at 11:00pm
Well, last time I messed up on the head/neck scarf joint. The two mating surfaces weren't 100% flat and so when I clamped one side down, the two pieces rolled a bit, and I didn't notice it until after the two pieces had dried that there was a big gap on the other side. (Sloppy wood working, I know. Well, I'm just a beginner at wood working. I also screwed up my 3-string head/neck assembly (my other on-going project) by using super (crazy) glue to glue on cut nails as frets. Lesson: Forget using super glue! Maybe slower drying epoxy would work. I may be able to salvage my 3-string head and neck assembly, but I'll have to pry off the frets and do a lot of sanding, then re-stain and re-varnish it.) Well, since then I have made a lot of progress on my new head/neck assembly for my concert sized ukulele which I will describe in this post.

1.) On this build, I made the scarf cut joint with a "short head" rather than the "long head" as I had done with my last attempt. With the short cut head, after the scarf cut is made, the head is flipped over and the diagonal side (scarf cut side) of the head is glued to the bottom side of the neck. This differs from the long cut head, where the bottom of the head is glued to the diagonal side (scarf cut side) of the neck. Both methods produce a head with a 15 degree slope, but the "short head" method places the scarf joint entirely on the headstock, while the "long head" method places the scarf joint entirely on the neck, below the nut. I decided I liked the "short head" method better because when I glue on the "wings" (side pieces glued onto the head to widen it to at least 2'' wide), these side pieces strengthen the scarf joint. A diagram will probably make my words more understandable.

To resolve the "probable area of difficulty", I cut my wings (side pieces) a half inch longer so I'd have more material to work with. In the end, I filed most of the extra wood away, just leaving enough to cover the red area in the diagram above. My new head/neck assembly also differs from the drawing above in that the side pieces (wings) are 0.75'' wide, rather than 0.25" wide. I did this because I just have hand tools, and I thought one cut down the middle of a 1.5'' board would be easier than two 1/4" cuts down the length of the board. So, my new headstock is a very squarish 5'' long by 3'' wide. The following diagram was used to figure out my tuner placement and includes the 0.75" side boards in its dimensions. I printed this diagram at something near to full size and used it as a pattern to drill my holes for the tuners.




2.) I've also slotted the lid of the cigar box so that the head/neck assembly would pierce the cigar box as per my original drawing. However, this cigar box's lid was not as deep as the last one, so I decided to slot the neck about 1/4'' in two places so you could close the cigar box around the neck. The two lower box edges fit nicely into these two neck slots. Eventually I'll glue the neck to the top of the box, but after most of the project is done. There is also a shallow 1/8" "hollow" on the fret side of the head/neck assembly that will provide clearance for the sound board (top of the cigar box) to vibrate more freely. I am also thinking about gluing shut the lid, but I haven't decided yet. I do want to make some sound holes in the cigar box. I'll need a special drill bit (or something) to cut that. All my drill bits are 1/4" and smaller. I was thinking of a couple 1/2" holes followed by a couple 3/8" holes. Then put grommets on to make them look a bit spiffier.

3.) This time I also installed frets using real fret wire (medium size) and a hobby "razor" saw. They seem to be working, but I have yet to test to see if they are properly placed for good intonation. I used the WFret.com program to calculate the fret spacing, having had pretty good luck before using that program. Now I am staining and varnishing the head/neck assembly. I'm using polyurethane (not really varnish). The cigar box has some paper edger decorations, so I am thinking of varnishing the box as well. Do any of you know if this is a good practice? Will have to inquire of one of the forums. It'll be a couple more days for the varnishing to be complete (I want to do 2 coats). In the mean time, I have another 3-string canjo in the works using a fair sized spaghetti sauce can and will orient the can at a right angle to the canjo stick. The canjo stick's head will also be slotted in a manner similar to my McNally Strumstick.

Oh, I forgot to mention, the fretting on my new head/neck assembly is diatonically spaced, making the instrument more of a stick dulcimer (strum stick), but with a short neck. I was thinking that I could do two sets of nuts and bridges which would be removable (just held on by string tension). One would have the strings equally spaced across the neck, while the other would support dual melody strings for the first pair of stings (spaced 1/8" apart, and the other 2 strings (string 3 and string 4) spaced 3/8'' away from string two. I'm not sure if I can tune it to GCEA and get a diatonic scale that is useful, but it would be cool if I could produce an instrument that was either a 4-string ukulele, or a 4 string stick dulcimer, depending on which nut and bridge you use, and how you tuned the instrument. I am also planning to use ukulele strings, because nylon is easier on my finger tips and I like the more mellow (less twangy) sound they produce.

Any constructive comments on my build would be appreciated.









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CBG first time build - post #1

Posted by Stone Barnard on December 20, 2010 at 10:00am

Note: I realized after posting that the links will take you away from this page.

 

Hey there! This is the first post in a blog I will be keeping to document my first CBG build. As many of you reading this from Cigar Box Nation have been through this process many years ago I thought it would be fun to include you in my account of earning my 'strings'. (hahah.. strings, wings,that was good right?) Hopefully I can show other new comers that anybody can indeed build something that is useful and beautiful. I must add that I was an industrial design major in college, so I have a little more skill then the average person in building things. But my knowledge of these instruments is the same as anyone who has never seen one in person. Hopefully I will recruit several of you to assist me in my process. I will be taking as many pictures as I can and keeping the blog updated at least once a week.

 

As I learned in Design School several years ago, the best place to start is with an idea. Since I do not have an extensive background in instruments, specifically guitars, I knew I needed to look at as many examples as possible to get the idea in the first place. A quick run on Wikipedia.com produced a nice little history of the CBG and a picture that I found really useful.

 

9353727274?profile=original I knew that this style of guitar could be made in many different styles, but I did not expect to find the traditional versions so simple. I do find the idea of a simple build pleasing because the chance of success would be improved. However, I do not wish to construct something from a kit or that would not gain the attention of a seasoned vet. Out of all the simple builds available on the internet my favorite so far has been by GuitarIsMyLife with a nice breakdown of the several components. I also came across the documentary  Songs Inside The Box which I will definitely look into, although there are plenty of pictures of these amazing instruments there is little about the people who build them.

So my first task is going to be to design my CBG and see if it would be functional and what elements of the design would need to be changed. I'm also going to begin putting together a parts list with prices to develop an overall idea for the cost of the build. Again my goal here is not to produce a 'how to' but to document the process one would go through when attempting their first build.

Until next time.

-Stone 'Barnyard' Barnard

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Cigar Box Ukulele Project 1

Posted by Rand Moore on July 14, 2010 at 4:30am

I have found a couple sources for Cigar Boxes around my "summer home" in the SF Bay Area. I quickly made a one-stringer (diddly bow-like) CBG w/o frets, mainly to get the idea of how to attach the neck to the cigar box. Another goal was to make an instrument I could use to play around with a slider while using a chop stick to pound on the strings (a new style of playing), as well as picking while fretting with imaginary frets (also a new experience for me). Wish I knew more about how to play the Blues. My 5 y.o. daughter likes to fool around with this one- stringer as well, so I might just let her keep it as a toy. Anything to encourage her music interests. I can always add frets for her later.

Since all of the cigar boxes I've found are smaller than I imagined, I think they're probably best suited for use in a smaller instrument such as a ukulele. Fortunately, I'm familiar with ukes, and my favorite sized uke is the concert size (length = 24'' or 25'', a 15" scale with 17 or 18 frets, and 4 strings tuned GCEA). So I have been thinking about building a Cigar Box Ukulele (CBU). I'll use this Blog on CBN as my "thinking pad", and perhaps some of my ideas can be of use to other want-to-be Cigar Box luthiers (like me).

My first concern was how difficult it might be to reach the highest (pitched) frets (15, 16, 17 and 18) which are usually found on the part of the fretboard that overlays the body. With a somewhat bulky rectangular cigar box as a body, they might be hard to get to, so I decided I want to extend the neck a couple more inches so all the frets will be on the neck. To make sure this would work, I ran the Stew-Mac Fret Calculator to make sure I could get all the frets on a 10" neck. So, here's the fret positioning information for a 15" scale length ukulele:


As you can see, with a 15" scale length, you can have a 18 fret "fretboard" on the neck of 10" and have
5 more inches of space across the face of your cigar box before you reach the bridge.

Let's see. The cigar box I want to use is 7.75" wide x 8.0625" high x 2.75" deep. I want the bridge placed about 1/3 of the way across the cigar box from the tail piece. That's 2.58" across to the bridge, leaving 5.17" of space before the neck, where you'd strum with your right hand. But, the bridge will have to go (2.58 + 0.17 = ) 2.75" up from the tail piece to maintain the 15" scale length, with 5" on the box and 10" on the neck. Compare that to my 20 fret concert uke which has just under 4.75" of space between the last fret and the bridge. That's not bad. I never use those higher frets (19 & 20) anyways.

Time for another diagram.

Hmmm... Need to use larger print next time. Or, keep my diagrams smaller. Well, at least you can see the relative size and orientation of the parts.

By the way, this is not a left handed uke. I draw them as I hold them, not as the audience may see them. But, if you want a left handed CBU, all you need to do is to reverse the order of the strings. Everything else is symmetrical around the central axis running down the middle of the instrument, so it's good for right- or left-handed players.

The ruler above the neck shows the 15'' scale length, with 10" over the neck for the frets, and 5" over the box for picking and strumming. The nut and bridge will be a movable bridge (at least initially) so I can (hopefully) correct for any intonation problems, at least those related to nut and bridge height and placement. An instrument with "good intonation" is in tune throughout its entire scale, and that means my fret placement has to be exact, as well as good nut and bridge placement. Also, sometimes tilting the bridge counter-clockwise a millimeter or two can help with intonation problems caused by thicker middle and bass strings (but maybe not for the re-entrantly tuned 4th string - another problem to be solved later). So, it's probably a good thing to keep the bridge and nuts movable until you've completed your instrument build and have played with it a while and have had a chance to tinker with its setup to your satisfaction.

The ruler at the bottom of the diagram shows the length-over-all of the instrument, which should be (ideally) 24''. Mine is a bit short, I believe because of the short size of the cigar box resonator. Notice that the stick (neck) of my uke will run through the cigar box and come out the other end, by about 1". There I will either use some kind of bracket for a tail piece or drill 4 holes in the tail end of the stick and anchor the strings on this side using beads or something. I'll figure out those details later. I prefer this method of mounting the stick (neck) through the box because the stick (neck) will hold all the stress from the strings once they are tuned. That means I won't have to set up any internal bracing or figure out how to do any special neck-to-box joints. Keep it simple, Sam.

Notice I use two sound holes on either side of the four uke strings. This is pretty "un-uke-like", because most ukes have a larger single sound hole placed strategically under the strings like any acoustical guitar. However, this change is dictated by the fact that my uke will have a stick (neck) running down the middle of the box where a single sound hole would normally be placed. A stick covering most of the sound hole would make the sound hole pretty ineffective.

The Headstock

I usually begin at the head and work my way down. As the diagram above shows, the four strings will be run from the tuners on the headstock, across the nut, down the neck and across the cigar box to the bridge and are finally terminated at the tail piece. The strings are drawn 3/8'' apart, which is pretty standard for ukuleles and stick dulcimers. If you prefer 1/2" apart, you can do it with a wider stick (neck). The separation between the two outer strings and their respective edges of the neck is 3/16''. So, with 3/8'' string-to-string spacing, the width of the neck should be very close to 1.5''. For 1/2'' sting-to-string spacing, the width of the neck should be close to 2", providing a 1/4'' separation on each side from the two outer strings and their respective edges of the neck.

However, on a typical ukulele, the neck usually has a taper of about a centimeter on both sides, getting wider as it approaches the body. But, for simplicity's sake, I am NOT going to cut the neck with a taper. This decision is based on the fact that I am working with hand tools (no table saws, etc.) and because my wood working skills are rather limited. For these same reasons, the back of the neck will have minimal rounding and there will be no heel on the neck as used on traditional ukuleles to connect the neck to the sound box.

As you can see, the headstock design will be rather plain and simple. Like your typical ukulele or guitar, the head will be tilted "downward" by about 15 degrees. This usually involves cutting the head-piece off the neck at a 15 degree angle, flipping the head over and gluing it back on to the neck. I'm told that this is called a "scarf joint" and that the shallower the angle, the stronger the joint. So, a 15 degree angle will be stronger than say a 45 degree angle because there is a larger surface area for the glue to hold the two parts together. You can also use wood dowels or screws for additional strength, but my experience (so far) indicates that they aren't really necessary if you are using a good wood glue, are clamping the pieces together and letting it dry overnight.

My headstock will be 5'' long, 2'' wide, and 7/16" deep. Yes, I know the diagram says 0.75'' (3/4"), but I forgot to take into account the requirement of the tuners that the headstock be 7/16'' deep. Your tuners may differ, so double check that measurement with your tuners. I'll have to figure out how to plane down the head to 7/16". Lot's of planing, filing and sanding, I guess.

The headstock build will also involve gluing two "wings" or side pieces on to widen the headstock to at least 2 inches. The 4 separate tuners will be placed in a "2 by 2" configuration with about two inches separation so there will be plenty of room to route the strings to their respective tuners. Hmmm... Since I have to add to the width of the head, and plane it down by 1/4''; maybe I should go back to the hardware store to buy a piece of wood that is already 5'' x 2'' x 7/16'' (more likely 1/2'' deep), and preferably in the same kind of wood. That would simplify the job a lot.

Also, in the diagram above, I have added maybe 1/4'' to the length of the neck between the nut and the headstock for a 'slop factor", as my hand-sawn cuts aren't usually as accurate as I would hope.

I'll be focusing more on the headstock on my next post.


- Rand.









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