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haven't decided what it is going to be yet...found a solid mahogany cigar box, making a mahogany neck, slotted some rosewood @ around 13" scale(i don't recall). this is all wood i had on hand, i'm sorta making it up as i go along. never built an acoustic instrument before so i'm worried about tension tearing it apart....yet i don't want to overbrace. heck it is just for fun though....
i've got some mandolin fretwire which i have never worked with before....any thoughts on radius? i'm prettymuch planning on 9.5"....or flat. which would be a better choice for such a small scale? i don't have any other radius blocks...

I think little instruments like this are a lot of fun. The only advice I can give (and my advice won't be worth much) is that four strings would put less stress on it than eight strings. And gut strings might be easier on the top than steel strings. But I'm sure you could brace it to handle almost any string configuration. How is the neck attached?

Nice box, CBG's or I guess CBM's, or CBU's are a blast and a great way to get some building chops without spending a fortune. I would drift towards the ukelele version. Less tension, 4 strings destined for an open tuning. Have fun, learn something and apply what you learned to the next. Definitely keep posting pics of this though. Thanks for posting.
Rob

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i haven't attached the neck yet ! i didn't really think it through to well...i think i'll just use a dowl or two; i'm worried about lateral movement mostly...
i plan on having the fingerboard running out over the soundboard, like most acoustic guitars, but i am wondering" should i put the frets in 1st, then glue on the fingerboard? or fret it after? because i am afraid of tapping the frets in over the soundboard; that mahogany is very weak
also the cigar box is very old and dried up; i was wondering what i could moisturize it with, if i plan on using shellac/nitro to finish it with? or should i leave it thirsty/as is(i think the cigar box is 30+ years old! and it never had a finish on it)

making dot inlays with aluminum wire

made more progress with the fretboard. i don't know why this is taking me so long; i guess because i am making it up as i go along. still don't know how the strings are going to be anchored, i think i'm going to go with a tailpiece and movable violin type bridge....except the fretboard is on the same plane as the instrument top. i radiused the FB at 9.5", as thats the only radius i have
on the positive side, it is very resonant when knocked about. next stop, i guess i will put a hole or two in the top, then glue it on.
...by the way, that neck is just butt-jointed with hide glue, nothing elaborate...i'm betting it will crumple as soon as i start tensioning the strings....so, as a last ditch fortification i added a 1/4" oak dowel, in the only position i could get at with a drill....oh well, i'll keep it tumed low, if it holds

still not sure about the tailpiece. think i'm going to go with a piece of heavy sheet metal or a bent spoon or something. anyone have any ideas? fingerboard soundhole cutout still needs to be tweaked....

Gotta like those Te Amos. Nice work.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

so far this project is a complete failure do to complete lack of volume! i am astounded at how quiet it is, it is about the same as an unplugged electric, and even worse with nylon strings....i am just surprised because in handling the instrument during construction, it seemed very resonant and musical.
initially i made a rosewood tailpiece and mounted it on the rear, and used a sliding "violin" style bridge...
so tonight, i made a regular flat top bridge(rosewood also) and after removing a patch of laquer, i glued it on.... but i didn't design or brace for the strings to anchor to the top plate, so i know whats going to happen when i tune up tomorrow!
i think i will make a video of the top popping off !
oh well, i guess i can salvage the neck and make a proper body this winter.
almost forgot to mention, i got a set of these tuners this spring and one of them does not work due to slipping; i for one do not recommend these overpriced things:
http://www.lmii.com/CartTwo/thirdproduc ... g+Machines

The only way the project can be a failure is if you are not learning anything. Does that strut on the top from heel to tail touch the top? That will kill any acoustic action you may get. Did you brace the top? Glue it down? If it did not sag just a touch when you strung it, it was over braced. I'm not buying that the Gotoh tuners are slipping, good chance it was some other movement.

I really like the idea of CGB, but as you may have noticed, the neck is where a ton of the work is, if you are going to go through all that, make a body that is comfortable and resonant. IMO of course.
Post the video.
Rob

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the top is glued to the top brace, and the brace indeed makes full contact with each end. as you can see i know nothing about bracing among other things; i wanted to keep it simple and rigid...its one of the few things thats holding the top down! i did not know; kinda makes sense now if i think of the top as a speaker diaphragm
anyway, the tuners have a set screw in them, so the post heights are adjustable....and now 2 of the tuners are screwy. more than slipping: i crank and crank the key, the gear turns, but the shaft does not. maybe i stripped something inside, i don't know.
LMI said they would replace them too; gotta love that
anyway i can salvage the neck easily enough and make a proper body; not like much effort went into the cigar box!
anyway with 2 tuners out i can't even string it up really, but i can sure tell that it is a piece of crap!

quick post of the fret job....will post final job soon. "pre ban" rosewood by the way, from a major local manufacturer, from the '80s(family connection)...i have quite a bit of it, didn't really realize the value/contraband status of it till the last few weeks(via here). would it be legal for me to sell an instrument made with brazilian rosewood that has been in the family since the 80s? i also have jet black ebony. most of this stuff has flaws, ie, errant drill holes or side chips, but most can be creatively worked around.
i had a bit of trouble with this narrower fret wire; it wanted to flop over on me as i tapped on it. you can see towards the edges some of it is mashed down at a more radical angle.....nothing that a fret level and crowning cant fix though....

looks pretty good to me.
I have built one of those, the top should not need bracing as the sides are very close together. Kind of like a ladder braced guitar with the ladders being the sides. The sides are the braceing. The scale length is important. I used 21 inches or something, mandola maybe? I strung x lightly with silk and steels and tuned it high up to G was really quite loud.

The most important thing I discovered is that the back should be free of obstructions bracing too. What I did was glue in another back on the inside in a sense making it twice as thick. I did the same with the two ends and used a small neck block and tail block. The box was very loud and resonate so I beleive this may have increased the sound output as the vibrations had to go to the top, as the rest was too heavy. It is a six string.

I think yours looks great and with some experimenting you could have a really fine cigarbox guitar.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

this thing was an abject failure. for one the gotoh tuners were hunks of dysfunctional crap, so i couldn't even tension the strings up. the 2 strings i did manage to tighten up, well, the instrument was dead quiet. i didn't understand acoustic architecture at all then, as in, ZERO, so it was all my fault. i sawed the neck off a few weeks ago; hopefully some day it will be part of a functional instrument
i have only ever made bolt on neck electrics up till now

Too bad about the tuner at least thyere replaciong it. The use of a pinned bridge worked for me.
Too build an acoustic guitar.
A good plan from someone like GAL is a good idea but small experiments like this cigar boxare exclnt in gaining an understanding of just what is going on in the basic engineering.
I still liked the look of that design the way the hole and FB go together. Are you going to try again?

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

I still won't buy the failure part. You had to have learned something, and enjoyed the process. If you want to move on and make some other things, then it was a success. One of the comments I heard on this forum when I posted one of my hideous experiments was about the goal of the build. If your goal was to give Somogyi a run for his money with the cbg, then yeah I guess it was a failure, but if your goal was to experiment with some lutherie processes without spending a bunch of cash, then I believe it was successful.

I worked with the students making these 2 cbg's, I was pretty convinced I was a failure as a teacher by the time we were done, but when the smoke of adolescent attitude cleared in the end, they loved it.
Rob

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