This is a Canjo. Part Can, part Banjo. I call it "Thunderstruck". I made it last winter on the request of an important friend. I forgot to take pictures of the canjo in progress, however I will make some recreation photos for this instructable (I should just make a new one but I've got too many other projects on the table.). This is my first instructable and my first instrument.
There are lots of great banjo making resources online that I accessed for this build. And all can be found with a simple web search. I found them all very helpful, but they often got very technical, I just wanted to build one to see how it sounded and go from there. I am neither a luthier or musician, so I consulted both for feed back at times. If you don't have access to a luthier or musician you should make more friends.
Step 1: Materials and Tools
A Can. I used and old one gallon turps can. I painted mine but you could leave yours how it is.
One block of wood: 1.5"x3"x26"
Most recommend rock-maple. I didn't have any and didn't want to spend a fortune, so I used some Beechwood I had laying around. It's similar in color, less dense but a sturdy hardwood. I also laminated the neck with 3/16" strips of purpleheart and mahogany.)
The Fretboard I ordered this precut. It is rosewood.
2, 12" 1/4"-20 threaded rods
1/4"-20 locknuts, washers and threaded insert.
1, 1/4"-20 brass bolt
4 tuning pegs and one fifth-string tuning peg.
Fretwire (ordered online)
and a fork.
Jigsaw or Bandsaw
rasp or drawknife
punch or nail-set
router (optional but helpful)
dremel (optional but helpful)
Step 2: R. & D. and Drawing.
First thing I did was lots of research. Online and measuring banjo necks for sizing. I think the most important thing here is getting the scale correct. The fretboard I ordered was a five string, 26 3/16th scale, non-radius, 22 slotted fretboard.
From what I've read the scale means the distance from the nut to the bridge. (but I have no idea, they all seem to be a little different.)
If you can find a banjo you like you can copy the measurements and angles.
Once I settled on the size of the neck I drew the top view and side view profiles to scale on craft paper and cut them out.
Step 3: Lamination
You need to start with a block of wood that is about 1.5"x3"x26"
I made a block by laminating two 1"x2.5" pieces of Beechwood with two pieces of mahogany and one piece of purpleheart between them.
As I mentioned most recommend rock-maple. You can use any type of wood I suppose.
You could make the neck from a single block of wood. There are ideas that lamination is stronger, and it may be. For me it was about what was laying about in the shop.
This can be tricky. If you are new to a complex glue-up you need two things. Enough wood glue, plenty of clamps. and lots of patience.
First: I put down wax paper so clean up is easy and the work piece doesn't get stuck to the table.
Second: With a cheap brush or old credit card spread the glue on all surfaces to be glued.
Third: Keeping in mind you don't have forever at this step, layer your pieces and clamp evenly.
(This last step is difficult. Once glue is between the pieces they want to slide around and out of place. I dont have a technique for this, I just work with it until it stays put. But I suppose one could glue these laminates in stages and wait for it to dry before gluing to the next piece.)
Step 4: Truss Rod or No Truss Rod
*At this point, before you cut the profile, you must decide if you want to add a truss-rod in your neck. A truss-rod allows you to adjust the bend in the neck to accommodate the tension of the strings.
As it was an added complication and cost I decided to skip it and get on with the project. This is my first banjo so if its a problem I'll try a truss-rod in the future.
If you want a truss-rod it is a matter of routing or dadoing a 1/4"x1/4" channel down the center of the top of the neck and epoxying the rod in and the fretboard will cover this channel. Having never done it, I cannot get too specific about this. But I imagine it would be easier to cut this channel before cutting the profile.
Step 5: Cut Your Profile.
-On with the cutting.
Once the glue has set and you got some free time, either print or draw your profiles out full scale and cut them out. Then Transfer your drawings to the work piece. You should have a profile for the top view and for the side view.
After transferring your drawings you will roughly cut out your profiles with a jigsaw or ideally a bandsaw. Leave about a 1/16" or 1/8" margin from your drawing.
(I only have a jig saw but I made it work by going slow and making sure the blade didn't wander too much.)
After this step you should have something that starts to look like a banjo neck!
Step 6: Carve Out the Form
From this point I used a rasp, a sure-form and a file to carve out the curvature of the underside of the neck. I imagine a draw-knife would make this easier.
Your work at this point can still be a little rough. There is lots of sanding in upcoming steps. You can also cut curved forms from cardboard to check your progress.
Take it slow and steady. every once in a while hold the work piece in your hands to see how it feels or compare to another banjo.
Step 7: Sanding the Top for the Fretboard
I was told the top of the neck should be dead flat. So I glued some sand paper to a board and checked it with a straight edge to make sure the jig was flat.
Then I put the neck fret side down and sanded carefully until It was as flat as I could get it. I checked often with a straight edge to see my progress and to make sure I wasn't making things worse.
Later I was told by a musician that some bend in the neck is good for keeping the strings off the frets.
Step 8: Gluing the Fretboard
This is much like the lamination step, with the added concern of lining up the frets perpendicular to the center line of the neck.
The fretboard came as a 2" x 19-1/2" x 3/16" piece of rosewood with the frets precut. When it's glued to the handle much of it over hangs and needs to be trimmed after gluing.
There ideas about how to sort out this geometric cluster-jam and where that center line is supposed to be. I just went with the line made by the laminated parts.
I marked the center of the fretboard at both ends and lined them up with one of the lamination joints running down the center of the neck.
Again, once glue is applied things get slippery. Clamp the hell out of this with a straight board on top of the fret board to even out the clamping pressure, while at the same time double checking your alignment. (A dry-run might be a good idea.)
After the glue had dried I took my router and flush trimmed the fretboard to the neck. This could be done carefully with a saw and then sanded flush. But they make flush trim bits for this kind of thing.
Step 9: Edge Banding
This step is optional.
Because I wanted to hide the tangs of the frets I put a smaller bearing on my flushtrim bit and routed a 3/16" wide x1/8" deep channel down the sides of the fretboard.
Then I glued in a strip of 3/16"x1/8" purpleheart down both sides of the fretboard. The bump out near the fifth string tuning knob required that I steam this banding at the bend so it would wrap around that bump cleanly.
Step 10: Drilling
A drill press will help this step a lot. I don't have one so I just did the best I could with my cordless.
There are three things to be drilled.
1. the tuning peg holes on the end of the neck
2. the fifth string hole (tapered)
3. the mounting holes at the end of the heel for the threaded rod.
1. Locate where you want your holes for the tuning pegs. I don't know how you're supposed to sort out this geometric nightmare. All I know is you don't want the strings in the back row to hit the pegs in the front row.
I was told that I should have done this layout differently but I forget how.
2. Drill the hole for the fifth string peg on the side of the neck just behind the bump out. This hole should be tapered, so I started with a smaller hole then I used a dremel to widen it near the opening til it seemed like the peg would fit.
3. Drill two holes big enough to fit a 1/4"-20 threaded insert into the heel where it will attach to the can. Then insert the inserts. Make these holes as dead on as you can. They should be inline with the center of the banjo. The spacing of them is up to you. I think mine were about an inch and a half apart.
Step 11: SANDING
Sand the entire thing except the top of the fretboard.
Sand out all the scratches from the rasp and sand it smooth.
I started at 80 grit and worked to 1500. 1500 might be excessive but sanding is fun.
Step 12: Finishing
I was told to use waterlox gloss by a luthier friend. He recommended a coat a day for ten days. I did 12 coats.
I suppose there are other finishes one could use. Try them all and see what works.
The Fretboard does not get a finish coat!
Try really hard not to get any on the fret board. Don't trust tape at this step. Do this in a well lit area. Apply conservatively near the fretboard to avoid drips.
I speak from experience. I lucked out and my drips along the fretboard aren't easily noticed.
Step 13: Fretting
This part is tough. (insert fretting joke here.) You need to cut the frets a little oversize, you will be filing them down to size after install.
Then, here is where if you've edge-banded you'll be cursing me, you need to cut or file the tang of the fret back so it does not hit the edge-band. This job is tedious at best. I used a dremel with a cut off wheel and that sped things up a little. It was still a lot of work.
If you didn't edg-band just proceed to the next step
Once your fret is cut, tap it into the slot on the fretboard. Prop up the neck on a raised surface with a towel or some padding. Then use a rubber mallet to tap the frets in place. Preferably use a mallet that does not mar the surface of the fretboard (or just put put a rag down on top of the fret). They make tools for this job if you want to spend an arm and a leg on a tool you may only use once, go for it.
**This next step is important! Skipping this may make strings hit some of the frets which will cause the banjo to sound out of tune or flat or something.**
After all the frets are in place hold a straight edge along them to see if any are proud. If there are, tap them some more or file them down with some emory paper until all the tops of the frets are in plane.
Then carefully file down the ends of all the frets until they are at a nice angle and wont catch on things like sleeves. You can sand them with emory paper after this to get them really smooth if you like.
Step 14: Fifth String Peg
Pound that sucker in. Unscrew the knob so you don't crack it. And use some towels for padding under the neck so that you don't mess up that nice finish you worked on.
Alternatively you can use a clamp and ease the peg into place.
Step 15: Can Prep
Remember those inserts in the heel? On the top and bottom of the can measure out two corresponding holes and punch or drill out these holes til you can fit a 1/4" threaded rod through them.
Step 16: Fork
This fork takes the string ends. Drill a 1/4" hole in it then bend it like the picture shows.
Step 17: Assemble
Thread your two 1/4" rods into the inserts in the heel. Then pass those rods through the can. Put that fork on the top bolt and attach with washers and lock-nuts. Don't tighten too much or you'll crush the can.
Screw on the remaining tuning pegs.
Add a nut (1/4"-20 brass bolt) and string up, add the bridge and Tune.
We took this to a professional musician and had him tune it for us.
He got it sounding real nice (Sounds tinny and a bit quiet but nice). He gave some tips for any future canjos... I can't remember what those tips were though.
Step 18: End Notes
I added this little bit of inlay with purpleheart and beechwood on the bottom of the heel. Not required but fun and it looks nice too.
I had a video somewhere of this thing in action but can't find it now. Will have to update this when I do.
It's a little light at the base, which is kind of weird I was told.
Now you can practice you're favorite AC/DC song in the park.