Build Notes

Name:
Location: Dunwich, MA

Monday, June 26, 2006

But it's Perfectly Good!


Craig's List Score
Originally uploaded by Usonian.
I scored an old Harmony Marquis banjo from Craig's List last Friday. Sight unseen I figured I could harvest the tailpiece, tension hoop, tension hooks, nuts, and (if it had them) hex or shoe bolts from the thing, hardware that would cost more to buy separately nowadays... and wind up with a spare neck, pot, and resonator as part of the deal.

Old brands like Harmony and Kay are the target of much scorn among banjo enthusiasts, and not without reason; they tended to be cheaply made, with pots made out of either bakelite or (as is the case with this Harmony) solid aluminum, and more often than not they'd be poorly set up... the end result being that aspiring banjo players would be frustrated away from the instrument.

Given that reputation, I was surprised how solid this banjo felt when I saw it... it looks like it's seen very little use over its 30ish+ year existence. There's some damage to the binding right near the 5th string peg and the fake mother of pearl inlays have yellowed a bit, but other than that the only wear I see are the sorts of nicks and scratches an instrument would pick up from kicking around the corner of somebody's living room without a case. There's even still a protective layer of paper on the truss rod cover, never removed.

Whoever strung the instrument last probably contributed a great deal to its non-use; strings were attached to the tailpiece in apparently random order, which means they're crossing the bridge at impossible angles and wanting to pull it out of position. The friction fifth string peg was loose, which would have been tremendously frustrating, and the other four strings were tuned way too low.

The yankee pragmatist in me observes all of this, and says, "Why, for the cost of a new set of strings and an hour or so of tinkering, you'd have a perfectly good knockabout resonator banjo!"

The only problem is, I really don't need a knockabout resonator banjo. I find myself concentrating on clawhammer playing these days, and one neglected resonator banjo is quite enough!

I also feel a little bit of guilt at the thought of dismantling this instrument, which seems like it never got a chance to make much music; with decent set-up, it could be an entirely servicable starter banjo for somebody... although I doubt I'd be able to get much more for it than what I paid, and it's certainly not worth spending the time or money to repair the binding and upgrade the tuning pegs. So, in the end I expect it will be coming apart as soon as I have a rim that needs hardware.

Saturday, June 10, 2006

Cigar Box Guitar #1, Part I

Cigar box Until I scrape together the cash to buy the rest of the hardware for my tenor banjo, I'm going to have a go at making a cigar box guitar. I'm making the scale a mandola-ish sort of length (17.5 inches) and giving it four strings.

There are quite a few people building cigar boxes out there, and there seems to be a bit of reverse snobbery around these instruments ("All you need is a box and a plank!", "Who needs to pay hundreds of dollars for one of them Martins when you can make a cigar box guitar at home in an afternoon!" "Listen to what I can do with three strings!", et cetera.)

I can understand the appeal of throwing together a functional instrument very quickly; it feels like I've been working on my tenor banjo forever. However, I'm not particularly interested in going to the "box and plank" extreme; I want something that I'll want to look at and play for more than an hour or two once it's complete.

Cigar box instruments seem like a good niche for a novice like me:

  • I can practice just about any aspect of building "real" instruments except for the body itself; neck, joints, inlay, finishing.
  • If I screw up somewhere, chances are good I'll only be out a few bucks.
  • Were I to start selling these things, expectations of fit and finish would be considerably lower than if I were making dreadnought clones, yet I could probably price them high enough to make a bit of profit which I could turn around and invest in tools and supplies for "real" instrument work.
I picked up a nice sturdy, wooden Encanto cigar box last weekend, and got to work.
Close Enough One of the first things I did was to make a miter box for cutting a low-angle scarf joint for the neck peghead joint. 15 degrees is the traditional angle, but my wooden, hand-cut miter box turned about a couple of degrees more acute than that.

For an instrument like this, I'm not particularly bothered by it. It means a little bit less surface area for the joint, but it should certainly be fine for nylon strings. When I move up to guitar necks I'll invest the time and money in making a jig like the one that Kathy Matsushita uses.
Scarf Joint The joint came out surprisingly clean despite being hand-cut with my rickety box.

I did a bit of sanding and then drilled a 1/4 hole more or less perpendicular to the joint, through both pieces. I glued everything up with a piece of 1/4 dowel through the hole. I'm not sure how much extra strength it will actually add to the joint, but I know I've seen it done on a couple of lutherie pages out there.
Cutting the soundhole My dad will be gratified to know that I've already found a use for the old jigsaw he gave me last month. I used this saw on innumerable Cub Scout projects twenty plus years ago, and bringing it home was a bit like seeing an old friend again.

To cut the soundhole I put a nail through the pivot point of the cigar box lid into a scrap of wood bolted to the jigsaw table, positioning everything so that the blade fell exactly at the outer radius of the circle from the pivot.

I also drilled a small hole in the lid ahead of time to let the blade through.
Soundhole Both of my soprano ukes' soundholes are 1.75 inches in diameter, so I decided to start there. I haven't decided whether it looks a tad too small or not.

There is quite a lot of information out there about the physics of soundholes and soundboxes, but not being a physicist a lot of it is over my head (not to mention overkill for a cigar box.) One thing I took away from what little reading I did is that too large of a soundhole relative to the size of the air chamber means poor response from the instrument top. Since you can always take more wood off, but you can never put it back on, 1.75 inches it is.

Not bad After the neck joint dried I cut the fret slots. I'm not using a fingerboard for this instrument, so I cut the slots before profiling the neck; much easier to make perpendicular cuts that way. It would have been even easier if I had cut the slots before gluing the peghead joint; that way the neck would have sat flat in the miter box.
Rough-cut, slotted neck After gluing on another small block of wood at the heel, and putting a maple veneer on the peghead to cover up the scarf joint, I went ahead and trimmed the neck profile and peghead outline.


Relatively instant gratification Compared to the stop-and-start progress on my still-incomplete tenor banjo, this thing is coming together lightning fast. This is at how things looked after two sessions in the workshop.


Rough Cut After a busy week I was eager to get back to this project in hopes of getting it strung this weekend. Maybe a little too eager; I tried using the bandsaw at an angle to rough out angles along the neck that will eventually be curves, and trimmed a little more away than I really wanted.

The thing I need to keep reminding myself is that I've already spent considerably more time on this thing than many people would, and that the neck will be perfectly functional despite being a little bit uneven in those spots.


Mostly Shaped Sanding has gone fairly quickly, although there's a stubborn spot of glue down at the heel block, and as always there are a few bandsaw nicks that may be deep enough to require filler, rather than sanding down everything around them. I need to get a bandsaw blade with a closer set.


Drilled Peghead Finally, I drilled holes in the peghead for the 1/4 posts of the guitar-type tuners I'll be using for the instrument.

I might actually have this thing fretted and strung by the end of my next session in the workshop!

Sunday, May 07, 2006

Shop Apron Lament

When I was working as an all-purpose special effects shop monkey in 1997, some guy came through the industrial park where I worked selling denim shop aprons for five bucks apiece. Unlike most of the peddlers that made the rounds periodically, this one had a useful product at a good price, and he sold quite a few aprons to us that afternoon.

Mine was quickly besmirched with paint, bondo, resin, cyanoacrylate, and all manner of other unhealthy substances. I probably could have pointed to each stain and told you which project it had come from.

When I left the shop for my first real full-time web design job, I took my apron with me, but living as I did in an aparment I didn't have any real use for it at home, and it spent most of the next 4 years in the storage space above our parking spot.

I think it was in a box of junk in the trunk of my 1966 Mustang when we left California. The Mustang was left behind, its fate uncertain. Ultimately it was sold and scrapped... no telling where the apron wound up.

As I spend more and more time working in my tiny shop now, I kind of wish I had that apron. The pay was terrible and hours could be miserable whenever a deadline approached, but there was a certain satisfaction to be had from making physical things for a living. The apron would have been a nice souvenir (and a way to keep most of the sawdust off my clothes.)

Tenor #1: Neck, Part XI


Fretted and Routed
Originally uploaded by Usonian.
In the end I decided to take a bit more wood off the neck behind the first several frets. Not a lot, but enough to feel perceptibly more slim.

With that done, I decided to try installing the rest of the frets. The going definitely got easier the more I did, and after the 18th one I almost felt like I knew what I was doing.

There are still a few frets that are not completely flush with the fingerboard. Rather than attack them with a hammer and block of wood again, I think I will build a caul to fit over one of my vice's jaws and press them that way.

With the frets in place, I went ahead and routed the star-shaped slot in the peghead. I'm not sure how, but I managed to cut it noticably crooked. As a result I had to go back and cut a few of the points much larger than I would have liked so that I'll be able to glue the star in straight. Between the black cyanoacrylate I have to glue it in, the black dye I'm using on the peghead, and layer of gloss finish that will ultimately cover the whole thing it shouldn't be too noticable.

Monday, May 01, 2006

Tenor #1: Neck, Part X

After gluing on the fingerboard, there were a couple of spots where saw marks in the neck were deeper than the edge of the fingerboard. Without doing any research on the preferred filler material for luthiers, I picked up a small tube of DAP Plastic Wood, which filled the space nicely. It's quite obvious, but it's on the side of the neck that will be facing the ground, and with the mahogany stain I also picked up over the weekend it should be fairly inoffensive when all is said and done.

I spent more time doing final shaping on the neck and peghead last night. It still feels a bit chunky, but due to my decision not to install a truss rod, I'm hesitant to take very much more wood off lest I weaken the neck.

On the other hand, I am also trying to be vigilant about not rushing things now that things are so far along. It's looking like I won't have much evening time to work on it this week anyway, so I'll continue to mull it over.

I also took the plunge and tried installing a fret. After doing just one manually, I have a better appreciation for some of the expensive gadgets Stewart MacDonald sells for fret installation. Someday when I have a drill press I'll probably shell out for a fret press caul.

Sunday, April 23, 2006

Tenor #1: Neck, Part IX


Fingerboard
Originally uploaded by Usonian.
Once again I followed Siminoff's technique for attaching the fingerboard, by using two small nails as positioning pins to hold the fingerboard in place during clamping.

I think everything went well... now it's a matter of sanding, then sanding, then sanding some more.

Thursday, April 20, 2006

Tenor #1: Neck, Part VIII

While playing my 5-string banjo last night I noticed that the last inlay marker before the twelfth fret is at the tenth fret, not the ninth as I placed it on my fretboard. A Google Image search confirmed that the 10th fret is the typical place to put it.

It's a good thing I'm not planning on selling this particular instrument when it's finished. It's a detail that will always bug me a little bit, but not quite enough to throw out the fingerboard.

Postscript
While playing guitar tonight I noticed that the marker is indeed on the ninth fret. Interesting. I'll have to cross-reference tenor guitars and mandolins too.

Wednesday, April 19, 2006

Tenor #1: Neck, Part VII


Tenor #1: Profiled Fingerboard
Originally uploaded by Usonian.
Although I saved about thirteen bucks by buying a rosewood guitar fretboard blank, I didn't appreciate how thick 1/4" would look on the relatively skinny tenor banjo neck. Next time I'll either spring for the 3/16" ebony from Stewmac, or see if I can find a 3/16" rosewood blank elsewhere.

Because the fingerboard is so thick, I decided to take a fair amount of additional wood off of the neck.

The nice thing about my shureform is that it removes wood quickly. The dangerous thing about my shureform is that it removes wood quickly.

Finally, I reached the point where it seemed like I really need the fingerboard in place before final shaping and sanding, so I took the plunge and cut the fingerboard to shape.

It looks like this will actually be an 18-fret tenor when all is said and done; my original calculations for the neck length were based on the position of the bridge on the 10 inch pot. It didn't occur to me to check the fret placement at that point, so it wasn't until I trimmed the fingerboard to size that I realized that there is just barely too little room for fret 19.

I'm not particularly upset... If I ever get proficient enough on tenor banjo that I actually need one with 19 frets, I will probably be happy to buy (or make) one.

Gluing the fingerboard on will be the scariest part of the operation so far. If the frets aren't absolutely perpendicular to the axis of the neck, playability will be seriously impaired.

For tonight, I will just bask in the satisfaction of how good the fretboard looks resting on the neck.

Tenor #1: Neck, Part VI


Tenor #1: 5th Fret
Originally uploaded by Usonian.
After gluing the inlay in place and patching the space with a mix of glue and rosewood dust, it was time to sand everything flush.

I started with 100 grit paper to get the worst of the excess glue off of the surface, then went to 150, 220, and finally down to steel wool.

It came out great, and I can't wait to do more on future instruments.