New instrument WIP - this time, a ukulele - Now completed...

[Kalimna]

Greetings folks,
Having has a wee bit of success with a pair of electric guitars last year, I have moved on to attempting a purely acoustic instrument. The end goal is to produce acoustic guitars, but I wanted to build something for my two boys, and figured that ukuleles would be more manageable (and certainly cheaper on materials) and a more appropriate size for a 3 1/2 and 1 1/2 year olds....
Anyway, sometime in April last year, I started milling up some pieces of ripply maple, afromosia, spruce and ebony to make a pair of concert ukuleles. Plans I purchased online from Georgia Luthier Supplies, and beyond the timber (excepting the ebony which had been purchased as a guitar fingerboard, now split into two fb's) which was essentially scraps, I only had to buy tuners, fretwire and strings.
The maple has quite a tight ripple to it, and may not have been the best choice as a starting project, but as with my two previous stringed efforts, the whole process so far has been one of learning, figuring out processes, d'oh moments, ahhhh buggerit moments and pleasure when something works.
Information on how to build acoustically has been absorbed from Cumpiano & Natelson, Hiscock, Obrien online tuts, and a few other internet resources. As in many aspects of woodworking, there are many ways to successfully skin a cat, and mine has been an amalgamation of many ideas. However, and unlike most current practice, I opted for free-form building (as per Cumpiano & Natelsons' bible on the subject) rather than go to the extra expense and effort (of both time and space) of building an outside mold. This has presented with a few particular issues, notably verticality of sides and absolute adherence to outline shape, but neither of these should prevent a workable instrument from being produced. And as I am in no particular rush to get them finished, production-run efficiency is not an issue. A further detour from normality has me using a butt-joint for the neck-body join, but more of that later.
So, before I begin with the photos, here is a breakdown of the two ukes.
A final note is that the photos may be from either build, but I shall try and keep them separate.

model - concert
scale - 15" (fretting template from Stew-Mac)
back & sides - ripply maple
soundboard - spruce offcut from archtop guitar wedges
neck - ripply maple for one, afromosia (ex laboratory worktop) for the other
fingerboard - ebony
binding - indian rosewood offcuts from acoustic guitar set
end wedge - padouk
bridge - padouk
finish - not decided, maybe a first stab at french polishing

First piccy, jointing the edges of the soundboard prior to glue up. Notice the wobbly, relatively wide grain.

Soundboard glued up thicknessed

Soundhole decoration channel trial run in some BnQ ply using trusty dremel and spiral bit. The soundhole itself is cut out using the same method, only routing a little deeper.

More routing. Despite the 'cheap and nastiness' of the dremel circle-cutting jig, it does work nicely, though difficult to fine tune. A suitably sized hole is pilot-drilled into both the soundboard and workboard underneath. This then accepts the 'spike' on the jig, about which the router rotates.

Decorative strips inlaid and trimmed (much kudos to anyone who can ID the timber the plane is made from )

Skipping ahead a wee bit, here are some of the soundboard braces being glued on. Unlike most modern acoustic guitars, it seems that ukes still have a flat top so the braces are straight pieces of spruce. Those adorning the back do have a radius routed onto their gluing edge to induce a slight curve to the back. Again, in a break from more modern teachings, I am using cam-clamps rather than a go-bar deck to clamp up the glueing. Even though these wooden clamps are relatively lightweight, there is still plenty of mass to induce an unpleasant twisting of the soundboard if inadvisedly handled.....

Here are both soundboards fully braced (though not carved yet), with an indian rosewood bridge patch. As to the bracing pattern - a little bit from the plans, a little imagination.

Right then, onto the neck. As with the previous guitar builds, i opted for a scarf joint to enable both a stronger headstock, and a more efficient use of the timber. I think i used two pieces of maple for the neck, however, hence the odd position of the sawcut. Previously i had used a bandsaw for this, rather important, cut but went for a handsaw this time.

Two new necks, cut surfaces handplaned (I still find it odd that some American luthiers will take the wood straight from a tablesaw cut and glue up without handplaning this critical joint) and awaiting glue up.

Glueing up the scarf joints. Note the unusual use of dining table and Warburtons bread wrapper. Unfortunately there was a little slippage of the scarf when clamps released, but nothing that cant be tidied up.

Right then, more to follow on the next post.

 

[Kalimna]

Okay, part 2 of the pictorial WIP. Here is a closer look at some of the bracing of the soundboard, along with the bridge patch. I would rather the job looked a little neater, but I'll leave that for future builds

Gratuitous chisel shot of the back braces, having been glued on, being carved. Note the indian rosewood central reinforcing strip. I have only chosen IR for acoutrements as I had a little scrap left over from an acoustic guitar set.

Further use of the dining table as a clamping jig. Here are the neck and tail blocks being glued on. Unfortunately (again) a little titebond-slide crept in, and they ended up not perfectly square to the midline. Not an absolute disaster, but one that has produced a lot of huffing and puffing.

Now we get to something a little more nerve-wracking. Bending the sides. Whilst i have bent a pair of guitar sides before (macassar ebony, under close tutelage from Mark Bailey of Bailey guitars), I have never attempted this at home. Fortunately, it went adequately. Despite the ripply nature of the maple and the tightness of the bends, I managed not to crack either of the four sides (two per uke). Having said that, there are quite a few unwanted bits of waviness now present. Shouldnt effect acoustic performance, but aesthetically less than perfect. Also, now that the sides are glued up, i have noticed that the sides do not quite represent a right angle to either the soundboard or the back.

The mechanism for bending the sides is either to place the un-bent sides in a former between spring steel slats and a heating blanket, or to free-form it over a hot pipe. The hot pipe is the traditional method, and considerably less wasteful of money and space. However, it is certainly less accurate, and requires a certain 'feel' for how the (lightly spritzed) wood behaves under temperature. I am, however, pleased with the result.

Once the bent sides have had the kerfing (strips of roughly triangular-cross-section wood with regular, frequent cuts to allow conformation to the instruments' sides) is glued, using, for instance, clothes pegs as clamps. This is then flattened off on a large flat sanding board, and glued to the soundboard. Applying adequate clamping pressure to both the sides, soundboard and neck and tail blocks at the same time is not entirely straightforward. A couple of practice runs were essential. Due to the physical size of the uke compared to an acoustic guitar, this step was particularly tricky.
Here is the finished article.

Unfortunately, once the clamps were removed, a few gaps were evident. This, I hoped, was not too much of a problem as : a) cyanoacrylate exists, and b) much of the gap will be removed anyway once the binding channels have been routed. The (nearly vertical) gap between the ends of the two sides is not a problem as it will be chiseled away to make space for the end wedge anyway.

Right then, I shall leave it there for now. I have a few more piccies to post up of progress so far - failed attempt at bolt-on for neck joint, edge binding, neck carving, fretboard and initial body sanding.

As always, ask any questions, and comment (good or bad!) as you see fit

Cheers,
Adam

 

[thick_mike]

I love musical instrument WIPs. Thank you for being so honest about shortcomings and work arounds, it gives people the confidence to have a go themselves.

 

[bodge]

Lovely job so far. =D>
I've not seen free form building done before so thanks for the insight. It looks a bit scary to me and I think I will stick with my outside moulds as I am not terribly accurate and it helps compensate for my inadequacies!
Looking forward to watching this build progress, especially the binding process, which is something else I struggle with.
Thanks for sharing Adam.

 

[Green]

Brilliant thread. Looking forward to any updates.

 

[Kalimna]

Thank you for your kind words so far
Mike - I have read in a few places that it takes about ten or so instruments to become proficient at consistency of build. Until then, I suppose there will just be a great many more work-arounds. I suppose one constantly interesting aspect of woodworking in particular is that mistakes are made (and if you arent making mistakes, then you are either perfect or arent trying hard enough ), and the frequency and manner in which these are overcome is what drives us forwards to improve. A workable instrument is something that anyone can have a go at (so long as they have the interest to do so), and all that specialised equipment brings is a degree of repeatability and a reduced learning curve.

Pete - Whilst I can certainly see the advantages of using a mold, I have gone the other way as that is how I was shown to do it. Also, in their book, Cumpiano & Natelson suggest that using a mold can introduce stresses if the shape is not exact and being 'forced' into a molds' outline. I am not entirely convinced of this, as there are so many highly respected luthiers who use molds. The free form advantages as I see it are :
a) less space taken up with jigs (How many luthiers does it take to screw in a lightbulb? Just one, but it will take them three months to build the jigs for it)
b) much easier (and less wasteful of MDF/ply) to introduce a new shape if desired
c) any touching up of the outline is much easier if you have a little experience bending by hand.
d) it really isnt as difficult as it might look - I have now bent two guitar sides, and four ukulele sides, and all of them are usable. OK, the ukes are a little wobbly in places, but in my defence, the bending radii are much tighter on a uke (and therefore harder), I didnt have anyone watching me and correcting as necessary (unlike with the guitar) and I probably chose less-than-ideal wood for the ukes. On your next instrument, if you have access to a hot pipe, try out some practice sides and see how you get on.

Green - thanks for the comment.

And now, here are a few more pictures. I left off with the sides just glued to the soundboard. Unfortunately I have missed out a couple of steps, photo wise, but the next jobs were to fabricate a method for drilling two holes in both the neckblock (bit of spruce in the body of the uke, to which the neck is attached) and also the heel of the neck. The idea was that I would use a 6mm dowel as a locating device, and a threaded insert and bolt to do the actual attaching. The way I *should* have done it was to pre-drill the two holes in the neckblock with a pillar drill prior to it being gluedd to the soundboard. I could then (once glued) line up the neck to the body and use appropriate sized brad-point drills to insert from inside the body, through the neck block, and mark the location on the heel where further holes would be drilled to take the insert and the dowel. However, I hadnt planned well enough, and ended up making a hole-drilling jig that I could use on both the glued-up neck block and heel (on the assumption that everything was at the correcct angle). Unfortunatley the jig had its' holes drilled out of alignment and when used I discovered that the neck was off the midline of the body by about 4mm. Which is a lot on a uke. Or a guitar. Or a tank, for that matter. So, the photos you see with the threaded insert and dowel holes in place are of Plan A. Plan B is to use a simple glued butt joint. As an aside, the maple of the neck is an absolute unpleasant thing to drill (and then screw in threaded insert) into endgrain.

Now, whilst the holes look quite off the midline, this photo is deceiving because the two sides do not exactly meet up in the midline. What you see is a gap off-centre.

A close up of the heel end, with insert, erm, inserted and the dowel hole already filled in. I would fill in the insert, but damned if I can extract it without damaging the neck itself. The white line on the ebony fingerboard is dead-centre, and does match up exactly with the neck centre line. The neck has been tapered at this point, and a little trimming is required of the fretboard. I have also started work on shaping the heel.

Unfortunately I havent any photo's of the fretboard being worked on, but it has been thicknessed to around 4mm, with the end given a rounded bevel. Fret slots cut with a fretsaw/mitre box/scale template purchased from StewMac. Their system is quite good, as it doesnt rely on the fretboard being totally square to begin with. All you have to do is line up the blank's centre line with that of the template, and then slide the template inside the mitre box whereby a pin engages with notches cut in the side of the template corresponding to fret positions.
Here is the neck with fretboard temporarily attached. Correct location is ensured by the placement of two small nails inserted through holes drilled through two of the fret slots into the neck a short way. Once glue is applied, the fretboard will then not slip.
The taper of the neck can be achieved in many ways (and exact geometry a function of string spacing, neck width and scale length), hand plane, bandsaw, spokeshave, table saw. I have chosen to use a top-bearing guided cutter on a 1" birch ply template I made for the 15" scale length. due to the narrowness of the template, I used a 1/4" shank cutter on a laminate trimmer, rather than the full size router.

Next, a gentle curve needs to be created on the sides. This is done by cutting a facet leading from just behind the waistline down to the neckblock. Thank you, Bahco coping saw. The peak of this facet is then reduced on a sanding board, then the remainder of the curve faired in. Another hands on approach whereby the alternative is to use sandpaper adhered to a heavy-duty workboard larger than the instrument being built (applies to ukes as much as guitars) that has a dished impression machined in to an exact radius (say 20 feet radius). It is possible to make these dished workboards at home, but is much easier to buy them. They will also impart a very slight angle to the edge of the instruments sides, allowing a better gluing surface (though how important this is, I remain unconvinced) for the back or soundboard.
Once the curve is created, kerfing is applied to the sides and sanded flush, and then the back is repeatedly test-fitted until each back-brace has been trimmed to allow a snug fit.

Once trimmed, it is time to glue the back to the sides. Three methods of clamping this delicate structure are utilised. A large number of spool clamps, a clamping caul for the entire rim, or a long piece of rubber stretched over the body, which rests on a workboard. This last method is the one I chose, the workboard studded with a multitude of bolts to allow quick and easy rubber stretching. This is a surprisingly quick way of applying a good deal of clamping pressure over the whole rim.

And the enclosed body, ready for the top and back to be trimmed flush with the sides. The sides then given a rough sanding to flatten any major wobbles prior to binding.

A close up of a bit where I trimmed the back a little too much prior to glue up. This wont be a problem as the binding channel will remove this blemish. You also get a nice idea of the nature of the ripple in the maple.

For the binding, please see next post. Ta muchly!

 

[Kalimna]

Before I started the binding job, I cut a wedge into the end where the sides meet. Into this recess, I glued a wedge of padouk outlined by the white-black0white strips. In theory, this should make for a neater job. Again, whilst the wedge looks off-centre in the photo, in actuality it is spot on.

Glue up. Note the warburtons wrapper again

The finished wedge, prior to trimming

Now for the binding. Of the two ways to do this (tedious hand method or quick router), I chose the machine method. Whilst it is quicker, it is also much, much quicker at destroying all the work done so far than the hand method.
The design for the edge binding was to use white-black-white strips either side of the main indian rosewood strip. The white-black-white on the soundboard did not require pre-bending, but both the IR and the w-b-w on the side did. This was done on the hot pipe again, and I very quickly recalled the frustration of trying to bend on the wide axis of the strip, not the narrow.
Glue up of the binding is a truly messy affair. One starts off at the neck end, applies a fair amount of glue (somehow to all surfaces) and slowly works around the sides, sellotaping along the way. A very simple idea.

So, cutting the channels. Again, the laminate trimmer was used with a rebate cutter and variety of bearings of different diameters. These were bought, again, from StewMac. And multiple tests are required to ensure adequate depth of channels (one for the sides, one for the top/back, forming a stepped rebate).
Resting on top is one of the pre-bent indian rosewood strips.
You will notice the kerfing showing through the channels - this is to be expected and not, for once, an error on my part. Once the binding has been glued on, structtural integrity will be restored.

Bending the indian rosewood on the hot pipe.

The binding and white-black-white strips all glued up and taped. It is extremely important to have a good, handy, supply of tape for this procedure.

The next morning, the tape was carefully removed.

The large excess of (now dried) Titebond was removed with a combination of scraping and sanding, the excess binding width removed in a similar fashion (unfortunately I was a little over zealous with a block plane and managed to trim a little *too* much in places - though you would be hard pushed to tell where) and the body sanded to 120 grit. Any gaps in the binding filled with cyano and sanded flush. Although I have a little sanding still to do, this is where I am at with the build. The next steps will be to apply finish to the body, carve to neck, finish neck, glue neck to body, fabricate bridge, glue bridge, install frets, install tuners, add strings, work out how to play the damn thing...

This gives a clearer idea of the w-b-w strips

And lastly, the front

I apologise for the wordiness of these two, in particular, posts, and hope you kept up to the end! Once I am a little further forward, I shall post up some more pics. But for now, ask any questions you may have, etc. Comments welcome too.

Cheers,
Adam

 

[marcros]

Adam,

Great build. What are you planning on finishing it with? That rippled maple could be made into one of many effects, but I would think on this, you will be going quite traditional, rather than a sunburst?!

Could we have a close up of your binding bending hot pipe- I had assumed that you meant a piece of cast iron pipe and a blow torch until you showed it in one picture.

Thanks

Mark

 

[MMUK]

Excellent =D> =D>

Unfortunately I have George Formby in my head now :twisted:

 

[bodge]

Could we have a close up of your binding bending hot pipe- I had assumed that you meant a piece of cast iron pipe and a blow torch until you showed it in one picture.

Thanks

Mark

Mark, it looks like Adam has a "posh" manufactured hot pipe from somewhere like StewMac or ToneTach, something like this:
http://www.stewmac.com/shop/Tools/Speci ... _Iron.html

I went the skinflint route and made my own as essentiall it is very simple. I used a round aluminium billet which was drilled length ways to accept a 600w cartridge heater (300w would have comfortably done the job) and wired through a household light dimmer switch to control the temperature. I then did a crude calibration with a cheap infra red thermometer from eBay. The whole lot cost less than £30.
This was an upgrade as I started out with (yes, you guessed it) A length of exhaust pipe held in the vice and heated with a plumbers propane torch.

 

[bodge]

Adam, I am suitably impressed, this is looking wonderful. Is the prufling plastic or fibre? I can't tell from the pictures. I really struggle with binding, especially wood binding, so I am in awe. I agree that t is mighty scary taking a router bit spinning at 30,000 rpm and attacking a body which has just taken many hours to build! One slip and it is expensive kindling.

I do use a hot pipe to bend sides (see post above) but I still use an outside mould to hold them in place while I glue on the top and back as I never seem to be able to get them quite right otherwise, not that they are perfect anyway! Kudos on the sides, as I recall, maple is quite unforgiving when bending and I can imagine curly maple is a nightmare.

 

[Kalimna]

Mark - the hot pipe is, indeed, as Pete suggests. I purchased the posh version (!) from StewMac back when the exchange rate was good, a few years ago now. Even with import duty etc, it worked out a wee bit cheaper than from any of the UK suppliers. I could have gone the home-built route, but there are some things I dont feel comfortable doing, and this is one of them. Kudos to anyone who can do it, however. One of the nice things about the StewMac version is that the cross section of the pipe is roughly teardrop shaped, which, although by no means essential, certainly has a (possibly placebo) positive effect when bending different radii. Cumpiano does suggest using a blowtorch and a slightly flattened pipe, but it's probably not as easily controllable.
With regards to the finish, I had initially thought of going down the PRS-stye mega-ripple approach (see Al Di Meola Prism guitar http://adhnans.files.wordpress.com/2010 ... ola-12.jpg) using black dye as a first coat which is then sanded back and the colour dyes added to 'pop' the grain. And using rattle can lacquer on top. However, I think that might be one step too far. I have used Tru-oil in the past, but wanted to try something different for an acoustic. On each of my home builds so far, I have attempted to introduce a new skill/technique. So the upshot is that I think I will attempt a french polish. Eeeek. To that end, I plan to apply finish to the body prior to glueing the neck. I have gone to 400 grit, and will do a grain-raising wipe with a damp cloth before going again to 400, maybe 600-800 if it is worth it. My main concern is having the padouk of the end-wedge bleed into either the purfling or the maple or the spruce.... We shall see.

MMUK - Yes indeedy, when Im cleaning windaes

Pete - Thank you Perhaps when it is finished I shall take a photo of the sides with a square held up against them - they slope in places enough to ski down... However, to answer your question, the purfling is, I think, pale wood and dyed fibre. It certainly seemed to split in one or two places as if it had a grain to it. If you can bend sides (however it is done), then you can bend wooden binding - just make it a little thinner than I did so it conforms a little easier. I think that wooden binding just looks nicer than plastic (I used snakewood on my course-built acoustic), and is worth the extra frustration.The curly maple bent OK, it was just that a little waviness was introduced (with the waves going from soundboard to back rather than neck to tail, if you get my meaning) where I didnt want it. Having said that, the curl in the wood was not too extreme on the sides. Either way, I shall go for something more forgiving for the next guitar!

Right then, I have just glued up the second side of the second uke (did it one side at a time this time) and rediscovered the principle of doing a trial run with the clamps. No major issue, but things were getting in the way that weren't there for the first side...

Cheers,
Adam

 

[n0legs]

What a lovely job, well done.

 

[joethedrummer]

Kalimna,,all that work deserves to make some sweet sounds,,utmost congratulations to you,,it would be good to hear the finished instrument,,maybe Youtube ?.
I have been restoring "el cheapo" electrics since retiring for youngsters to play and I have built a couple of cigar box guitars and know the good feeling when someone plays something that you have created.
Really looking forward to seeing and possibly hearing the results of your skills..

 

[Woodmonkey]

Adam, this is fascinating, I've always fancied having a go at making myself a guitar, as usual I underestimated just how much work is involved...
Would you say making an electric guitar is easier - surely must be?
Rich

 

[Silverbirch]

Hi Adam,
I found this very interesting, having dabbled in this area myself.
A great WIP.
I`d be careful of that bottle of Titebond near that carpet, though!

Ian

 

[Kalimna]

Thanks guys

Joe - Posting up something to YouTube would mean a couple of things. Making a video, editing and then working out how to upload it (neither have I done before), further, I have never actually played a uke before So, right now, I couldn't even tell you how it is tuned! Obviously the basics can't be much different to that of a guitar, but even then my skill with the strings is a wee bit less than I'm happy letting the world hear... Thanks for the encouragement though - we shall see. And yes, it is lovely hearing somebody else play (especially when they are damn good) an instrument you have helped to create. Possibly more so with an acoustic, as the sound is quite different from in front.

Rich - yes, there is definitely a lot more to building a guitar than first sight would suggest. More so with an acoustic. I remember thinking that carving the neck would be the tricksiest bit, but it's a walk in the park compared to getting the neck angle (in three planes) spot on, positioning the bridge correctly, seating the frets (and flattening/re-crowning them), even just sanding prior to applying a finish because of all those curves. Having said that, I have found it hugely rewarding, particularly when someone whose opinion I value asks me to make him one. I would say that an electric guitar has a slightly different set of procedures than an acoustic, not necessarily in themselves easier, but probably less critical to the end result. The choice of pickups is going to affect the sound a lot more than what body shape/wood, fingerboard, neck material etc is. Not something to be said for an acoustic.

Ian - I'd be interested to know how far your dabbling went? And whilst the carpet survived this time, an errant so lodge of TB did find the soundboard. Grrrr..

No more photos tonight, but I've glued the heelcap (more Indian rosewood) and fretboard (ebony) onto the neck. Still a heckuva lot of carving to do (thanks Mr Liogier rasp man) before making the bridge and finishing.

Cheers,
Adam

 

[bugbear]

Not wishing to derail this thread, but those interested in ukulele might find this blog of interest;

Seems to be "cloned" on two sites:

http://z11.invisionfree.com/Stringed_In ... ic=33&st=0

or

http://forum.ukuleleunderground.com/sho ... -my-Nephew

BugBear

 

[Kalimna]

Rightyo then, heres a little update - not too much thats new, but as I am building two ukes concurrently, I figured I could post images of both builds. And all the new errors on the second one!

So, to start with, the maple neck for uke no.1. Taken from the glued-up-but-still-square-stage, the first thing to do is to pare a ramp down from the fretboard side of the heel (bit that attaches neck to body) to the end-cap, making a roughly trapezoidal cross section. It is this that will be butt-jointed to the body. Ive done most of this in the piccy, the only thing left to do is trim the heel length and then glue on the heel cap. You will notice a very rough initial carve of the neck too. Also included is the indian rosewood offcut (from the full size guitar project) that will supply a piece for the end cap. And a rather delectable 21 yr old Glenfiddich (if Im not too mistaken, though it might have been a 10 yr cask Springbank).

My method for tapering the neck is to use a flush-cutting router bit and a scale-length-specific taper template on the neck, then glue the fretboard, then use another (bottom bearing) flush cutter to trim the fretboard, registering off the tapered neck. Easier to do than describe. Only, with a neck as narrow as a ukes', I had a nervous time with a laminate trimmer rather than the full size router I have previously used. It is also necessary to cut the slots in the fretboard prior to glue-up, maintaining a centre line at all times.
So here is the neck with the fretboard and heel cap glued on and roughly trimmed (hence the chisel). I have also rasped the primary facets for carving the profile of the neck. Again, a procedure hampered by the small size of the neck. I think it is a size 5 grain Liogier in use here.

Further on in the carving process, you will notice I have attempted to maintain a midline. Once I am happy with the rough profile (and it is beginning to look nicely rounded - the ripple in the maple appearing nicely), I will take the thickness (fretboard-rear of neck) down in a tapered fashion from one end to the other. Whilst it isint especially obvious here, shaping the transition from the heel to the neck was the trickiest part, as there wasnt much wood to play with, and I didnt want to rasp into the neck itself at this point.

The neck is now mostly carved, with just a few areas to tidy up (notwithstanding the headstock which needs a fair bit of tidying!) and the fretboard awaiting frets. I have attempted gluing on a two-piece veneer to the rear of the headstock for the first time, and whilst mostly OK, looks a little messy at the edges (even after the tidying up). But it gives a little idea of shape to the neck-headstock join area. The front of the headstock will receive a padouk veneer, to match the bridge.

One last job to complete following the sanding of a radius (thank you Mr Philly for the radius blocks) onto the front surface of the fretboard is to deepen the fret slots to accept the fretwire. Now, I shouldnt have had to do this, but I either didnt cut the slots deep enough to start with, or sanded too much afterwards. Either way, I contrived a means for holding a carved neck steady (odd bits of wood, cork sanding blocks, left hand) enough to allow the use of the fretsaw. Ebony is quite a brittle wood especially when as thin as it now is, and I had some concern that I would either cut right through or put too much pressure on it, thus snapping. Fortunately, neither happened and the frets went in nicely with only a few marks on the ebony to show for it.
Slots not deep enough, as exampled by the yellow arrows.

Frets being installed, tap at either end, then in the middle.

And that is roughly where I am up to with ukulele number one.

Following post shows uke no. 2

Cheers,
Adam

 

[Kalimna]

Right then, number two. Most of the process is indentical, but a few errors were noticed that I attempted to correct this time around.
On examining the soundboard (with glued on heel and tail blocks), I noticed the heel block was out of square. Now, I suspect the same was also true of uke no.1, but I didnt notice (though it would explain some of the problems I had squaring up the neck to the body). I decided to remove the neck block (courtesy of a flush cutting saw and paring away of residual spruce) and managed to do so without marring the soft spruce soundboard. The neck block was then squared up again and re-glued, this time near-as-damnit spot on.
Error noticed :

Block being removed :

Block tidied up :

Block re-glued :

The sides now had their kerfing glued on and sanded flush on one side, checking for twist/high/low spots on bandsaw table. These are then glued on, one side at a time, using an 'interesting' clamping arrangement. Of particular use is a piece of 1" (I think) birch ply that acts as a caul, spreading the clamping load over the whole side. Makes for a much less "will I crush the sides with a clamp" stressful glue up. You can see the dining table comes in handy again, as does a Warburtons Toastie bread wrapper to prevent inadvertent glue up to said table. I am not too bothered about excess glue squeeze-out as I can worry about aesthetics next in the future. For now, I want a good glue joint.

Both sides now attached, an arch now needs to be introduced to the rear edge of the sides. I did this (in the manner of Cumpiano/Natelson) by marking a primary facet (using some stiff sandpaper), cutting this away then using a large sanding board to fair in the curve. Once this has been done, and checked for symmetry and no gaps, the rear kerfing is glued on and planed/sanded flush. Then the back can have its' braces trimmed and the soundbox glued up, never again to be opened.

Marking the primary facet :

Gluing on the kerfing once the arch complete (only 18 months, and already helping out ). Please excuse the just-out-of-bed-look and dressing gown. :

Planing the kerfing flush :

The next few images attempt to explain the bolt-on system for holding the neck in place. Initialy, marked on the external centre-line, a hole is drilled through the neck block. The hole being about 2mm wider than the bolt going through (the apparently large gap to allow for misalignment of neck/hole drilling). Next, the neck is offered up to the body, checked for correct alignment, then a brad-point drill bit passed through from inside the soundbox to make a mark on the heel end of the neck. Two further holes are then drilled in the heel of the neck, one (vertically in this instance as I am using a butt-join) to accept the barrel nut, and another to accept the bolt. In theory, this allows for a very strong compression join that is easily separated. For the final instrument, the underside of the fretboard will also be glued to the top of the soundboard, which will also aassist with alignment.
First 'mock up', and it works. However, the spacer is there as I had yet to trim the bolt. The neck has had essentially no shaping work done on it yet, neither is the heel trimmed to length :

From the other side, showing the vertical hole :

And to re-instate a little of the lost strength, the next post will show a dowel being glued into the barrel-nut hole/

Cheers,
Adam