Building a Tenor Ukulele from a Stewart-MacDonald Kit

This is my third home-built ukulele though my first from a Stewart-MacDonald kit. I am thinking of building an acoustic guitar, so I want to build a smaller and simpler instrument first to get more familiar with the process. I should also get a nice ukulele out of the project. I bought two books on guitar making to help me: Guitarmaking: Tradition and Technology by by Jonathan Natelson and William Cumpiano and Build Your Own Acoustic Guitar: Complete Instructions and Full-Size Plans by Jonathan Kinkead.

December 27, 2013 Here are the kit pieces:

Solid mahogany neck, top, back and sides. The neck is carved, ready to sand. The solid rosewood fretboard is slotted and inlayed. The other parts are pre-cut though some trimming, scraping and sanding will be required.

December 29. First I need a jig. It will help align the parts during assembly. I drew a center line and lines for the sides of the jig, all perpendiular thanks to my carpenter's square:

Assembled. There are 2" drywall screws underneath holding the glued sides to the base:

I traced the shape of the ukulele body on the jig using the supplied template:

December 30. I used the jig to help draw a line on the tail of the body where the tail block will go. Then on a separate work board, I set up a clamp to attach the neck block. First I dry fitted the neck block, support block and clamp, then I disassembled them, put on Titebond wood glue and clamped everything together. I used wax paper to keep glue off the support block and off the plywood work surface:

I let it dry over night, then clamped the tail block in the same manner. Dry fitted:

Glued:

While the glue dried, I lined up braces on the top piece (soundboard) according to the template. Here they are dry-fitted.

December 31. I used weights to "clamp" the braces after adding glue:

Braces on the back:

There are four linings. I measured and trimmed the ends of each and dry-fitted them. Tail end:

Neck end. You can see the half-round cauls I made in the next three pictures.They keep the wasit of the ukulele narrow, so it conforms to the template:

The linings are dry-fitted with clothespins for clamps. The instructions insist: dry-fit everything first to make sure there are no surprises after the glue goes on:

The photo above shows that the sides are higher than the lining. This is correct. The tail end of the body is deeper than the neck end. The sides will be sanded down in a later step.

Back linings glued up:

I let them dry for 4 or 5 hours, then flipped the body over and installed the linings on the top side:

I added purfling to the sound hole. Once I had lined up the 5 thin pieces, they went right into the channel:

I had to trim the ends a couple times:

I have to wick superglue into the channel:

The gaps in the purfling will be hidden under the fingerboard. I used a wood chisel to trim and feather the braces:

Trimmed:

January 3, 2014. I couldn't find my belt sander so I threw caution to the wind and used my orbital sander to sand the sides down to the linings on the top and back of the body:

Then I finished sanding with a straight oak board covered with sandpaper to make sure the top and back were flat. Here come old flat top:

I nailed 4-penny nails into the perimeter of the jig base, then dry-fitted the body and top in the jig with two long rubber bands attached to the nails:

I glued it up, adding some additional clamping in the form of power tools:

Top glued on:

January 5, 2014. I have to trim the top so it is flush with the sides of the body. I have a medium size router but I am concerned about getting too close to the sides with it. I bought a trim router from Harbor Freight. It is smaller and should be easier to handle. Here it is on New Year's Day with trim guide attached:

I took the clamped assembly out to the garage due to the loud and dusty nature of routing. Here is the beginning of a first pass. I set the guide to leave a slight edge on the top, to err on the side of caution:

I tried to keep the router guide flat against the top with the bearing wheel against the side:

Here is a short video at the end of the first pass. This is instructive for me. I see I was not keeping the router as flat as I thought:

 

I went around a second time. I set the guide too close to the body at first, see below:

I adjusted the guide. Getting better:

The top, all trimmed:

I could sand these ridges out, but since I plan to add bindings to the edges, I will be routing these edges again. The trimmed body can now go back into the jig where I can glue on the back. Hidden away, top left, manufacturer and date.:

Glued up:

I can set up fretting while the glue dries. Here are fretting supplies. The fretboard, fret wire, fret hammer, nippers:

I made the fret hammer long ago. I modified it, giving it a domed head:

Here is the fret board held firmly between two clamps. To make side markers, I have to drill 1/8" into the fretboard with a 1/16" drill bit:

I marked a half-way line along the edge at each dot. Ready to drill:

All holes drilled. I put a marker on the drill bit to make sure I didn't go to far:

Stick in "dot material" with a tiny drop of super glue:

Cut it with a knife:

Sand them all with progressively finer sandpaper. I first used 80 grit on a piece of dowel to grind away the stub, then 150 grit without the dowel, then 220 grit:

I'll use a piece of 2x12 pine for a heavy, flat base for fret hammering. Here is the fretboard and first fret cut to size with 10" end nippers:

Hammer it in this way: tap in the two ends, then tap back and forth until the fret is seated in the slot:

Here is a short video:

 

About half-way done:

January 7. Finished fretting:

I glued the fretboard to the neck using one of the big rubberbands:

January 10. Close up of the fretboard, with overhanging frets, unsanded neck, dried glue all over:

I sanded the neck some, then filed the frets flush with the fretboard:

Frets all filed, neck sanded:

January 11. Here is the back, ready for trimming with the router:

I will add rosewood bindings, for practice and to make a more interesting instrument. This addition is not part of the kit so I have had to research the procedure by reading relevant sections in the two guitar building books referenced at the top of the page. Here is my home-made bending iron. I jammed a piece of distorted copper pipe over my old 100-watt soldering iron, secured it to the table:

I have to pre-bend the binding. First bend:

I'm learning:

To make the bends, I wet the rosewood with a soaked paper towel, then gently bent it, rocking it to warm the wood uniformly across the bend. It's a two-handed process (I'm holding the camera with my other hand in the picture below):

I routed binding channels on the top and back. Looks good from here:

January 12. Here is the back binding, ready to dry fit:

I dry fit the binding with about 6 pieces of tape, smoothed a couple of flat spots in the curved binding with the iron, then glued it on. Messy job. After I taped it with doubled painter's tape, I wrapped it with the two long rubber bands, to help secure the binding.

After 2 hours, I removed the rubber bands, flipped the body over and repeated the whole exercise with the top binding. Here is the bent binding:

Installed and drying:

January 13. Tape removed. Lots of cleaning up to do. Dried glue and high binding on the sides, will require lots of scraping to make it flush with the sides:

A scraper is a flat piece of steel filed straight on the edge, then rolled with a burnishing tool like the shiny shaft of a shock absorber. Burnishing puts a hook or burr on the edge or the scraper:

January 19. The scraper above required frequent sharpening and still didn't scrape like I wanted. Trying different pieces of metal, I found this piece of hacksaw blade to work well. It is probably made of high carbon steel. I couldn't file or burnish it, but I was able to grind a burr on it with the bench grinder. I welded the old scraper to it, to give me something to hold:

January 27. Done scraping.

I leveled the frets by first marking the tops of the frets with a black marker:

Then I sanded the frets on a flat surface (a piece of ceramic tile) to which was taped a piece of 500 grit sandpaper:

A few strokes were needed to remove the marker lines. I polished the frets with 0000 steel wool and then used a small Dremel polishing wheel and polishing compound.

Delicate operation ahead, drilling the holes for the dowel pins. I used a tape measure to mark the heel of the neck and front edge of the body as directed in the instructions:

I drilled holes in three steps, starting with a 1/16" drill (above) and ending with a 1/4" drill. Here are the holes drilled, test fitting the dowels:

Almost lines up:

January 28.

The fretboard is a tiny bit high so I enlarged the holes slightly by drilling a little more, pressing down on the drill to adjust for the slight height problem. I tested alignment using this jig, sanding and scraping the heel of the neck to get a better fit:

The instructions said to use this jig to clamp the neck and body down during gluing but I decided to use a band clamp to secure the heel of the neck against the body and a bar clamp to hold the fretboard against the body:

Here it is after I cleaned up the squeezed out glue with damp paper towels:

Looks good so far. I'm glad this part is done.

January 30. I got a couple of rulers from the big box home improvement store. I measured 17 and 3/32nd from the nut end of the fretboard and marked the saddle position on a piece of painter's tape:

I extended lines from the fretboard edges to the tape to make sure the bridge will be centered, then drew an outline of the bridge:

I scored the tape just inside the outline with a utility knife and pulled the outer tape away:

February 1-2. I filled any gaps between the binding and the body with Plastic Wood.

. Most gaps were small but there was a big gap at the end of one of the bindings. It shows here, when I was drilling holes for the neck dowels:

I filled the gap with "golden oak" colored Plastic Wood. I should have used a darker color but the "red mahogany" looked too red and "ebony" looked too dark. I got some new scrapers:

I used the small rectangluar one to scrape the excess filler away:

Then I stained the filler with "dark walnut" stain:

Acceptable.

I sanded all the mahogany with 500 grit sandpaper, then wiped all the mahogany with a damp cloth to raise the wood grain:

Holy cow. This wiping step really brings up the grain. The previously smooth surface became quite rough. I let it dry for one hour, sanded again with 500 grit paper, then repeated the wipe down:

Before I brush on lacquer, I want to personalize the headstock. I went with a single letter, made from a piece of curved and flattened copper wire. I used a Dremel sculpting bit to carve a C shape in the headstock after practicing on a piece of oak scrap:

Here is the result. I glued the C in with super glue, filled gaps with plastic wood and polished with 0000 steel wool:

February 3. I am using Minwax brushing lacquer to finish the mahogany parts. Here is my finishing station, the ventilated powder room:

I have masked off the fretboard and stuffed newspaper into the sound hole. I also glued a block of wood to the bridge tape so I will be able let the lacquer dry without disturbing it. The first step is to wipe the parts to be finished with mineral spirits:

After the mineral spirts dry, brush on the first coat of lacquer:

Let dry for 2 hours. Recoat twice with at least two hours between coats, go to bed.

February 4. I gave it one more coat in the morning. In the evening, I removed the tape from the bridge location:

I carefully scraped away the tape with a utility knife and dry-fitted the bridge with 2" deep throat clamps. I had to tape a small block of wood to the jaw of the clamp so the clamp arm would clear the brace between the sound hole and the bridge:

The obligatory dry fit using a caul (block of wood) to distribute the clamping force across the bridge:

Glued up:

Glue squeezed out on all sides. Good. I immediatedly wiped off the excess glue, first with dry paper towels, then with damp paper towels. I have learned the hard way that it is easiest to clean up the glue right away while it is still wet.

February 5. Here is the bridge after 24 hours, ready to string up:

Install tuners and nut. The nut is glued in with two drops of super glue:

With strings:

I have to adjust the action, the string height above the fretboard. Both the nut and the saddle will need adjustment.

February 6. I got out my 70's era feeler gauges. What's good for a 1960 VW Bug is good for a 2014 ukulele. The four gauges on the left add up to 0.090"

The string height at the first fret should be 0.015" and the height at the 12th fret should be 0.090". The strings are much higher than that. I got out my set of needle files from Harbor Freight, found a thin one and went to work on the nut. This photo shows the far slot filed down and the adjacent slot in progress:

February 7. The saddle must be sanded on the bottom to bring the strings closer to the frets. I drew a line with a felt marker on the side of the saddle and started sanding. Probably half way there in this photo:

I sanded off the marker line, inserted the saddle and tuned up the ukulele:

I was instantly happy with the tone. The strings are still a little high so I will repeat the last steps above, filing the nut and sanding the saddle a little more.

After further lowering the strings, the A string buzz slightly when plucked hard. What? I couldn't see where the string was touching anything but the nut and saddle. I did notice that the buzzing stopped when I pushed the string between the nut and the tuner. A troubleshooting page on the web tipped me off. The buzzing was coming from the string touching the nut in more than one place. The solution was to file the nut at an angle toward the tuner. Buzzing fixed. A final picture, string ends trimmed, tuned up:

This was an excellent introduction to the basics of acoustic instrument construction. While building this instrument I contemplated which guitar kit to buy. There are many kit suppliers, each with many choices. I decided to get a 000-28 kit from Martin Guitar through Blues Creek Guitars. See it built here.

February 2014