Finished Pics! A small acoustic 6-string for some special little people

[Andyjr1515]

Yes - I know, it's a guitar.  But it's for a good cause - it's for my two grandchildren for them to pick up and try if and when they are able to or want to, or use as a cricket bat or wall hanging if they don't.  And you never know - if they get hooked, they may well turn into bass players when they grow up  

 

I'm going tenor-uke size, but definitely a 6 string guitar.  Nothing against uke's but this way - if they do take a liking to it - they can progress to larger guitars without having to re-learn all of the chord patterns and tuning.

 

So spec is going to be :

17" scale

Ball-end nylons

tenor uke body size

Sitka Spruce top

Mahogany back and sides

Mahogany neck

Purpleheart fretboard

'Standard' X-brace

And, broadly, it is going to look like this:

 

I'm about halfway through - I'll do a few quick posts and then stuff will slow down to actual progress rate (that is, pedestrian! )  

 

 

 

Edited October 28, 2023 by Andyjr1515

[Andyjr1515]

I've found quite a bit of stuff for it in my various bits-boxes and rubbish bits-piles.  Including - and I have NO idea why I have a set of these - some classical guitar tuners!:

 

I found a mahogany offcut from one of my bass builds.  Would the tuners fit?  Wow - clearly this was meant to be     :

 

So, after cutting a headstock angle, out came my little Proxxon pillar drill:

 

Back to the band saw to cut the rear face of the headstock, then back to the pillar drill and scroll saw to drill/saw the slots:

 

Well - that went better than I thought it would!

 

 

[Chienmortbb]

36 minutes ago, Andyjr1515 said:

I've found quite a bit of stuff for it in my various bits-boxes and rubbish bits-piles.  Including - and I have NO idea why I have a set of these - some classical guitar tuners!:

 

I found a mahogany offcut from one of my bass builds.  Would the tuners fit?  Wow - clearly this was meant to be     :

 

So, after cutting a headstock angle, out came my little Proxxon pillar drill:

 

Back to the band saw to cut the rear face of the headstock, then back to the pillar drill and scroll saw to drill/saw the slots:

 

Well - that went better than I thought it would!

 

 

Those look suspiciously like Machine Heads Andy. 😉

[Richard R]

Hurrah! Another Andy build thread!  An oasis of calm civillised craftsmanship, sharp tools and gentle wit. A respite from the unrelenting depression of the news and most of the rest of the internet.

 

Following,  of course. 😁

 

[Andyjr1515]

For the fretboard, I had found an offcut of some purpleheart that I used for neck splices in the past.  I sliced a length off on the bandsaw and radiussed it with a radius block:

 

Then used a 24.75" (I think it was) scale in my fretting mitre jig starting at the 5th fret to give me the 17" scale:

 

 

Next I added some sawn strips of purpleheart to act as binding, curved to radius and taper using my little block plane:

 

[Andyjr1515]

As the purpleheart gets exposed to the light it will pinken markedly.  Originally, I was going to put a plain ebony headstock plate over the mahogany...but maybe a bit of purpleheart there too?

 

Got me thinking and experimenting.  Hmmm...and was there room for a swift in there too?  :

 

Then add some dots and frets to the fretboard - this might work:

 

Then back to the neck.  No trussrod needed but, as it is a mahogany neck, maybe a little extra stiffness would not go amiss - so I slotted the top for a couple of hollow carbon-fibre beams:

 

With that sorted, I could bandsaw the neck and start shaping that.  Before shaping the heel, I added an extension to its length.  The fretboard is just laid on top - it won't be glued on until the neck angle is fully sorted (a long time yet!):

 

 

Did a bit more carving to start sorting the neck profile and, in the same way that you can't have too many clamps, you can never have too many swifts!        

You can tell the age of my iphone by the colour aberrations of its camera!!

 

Starting to look like an acoustic guitar neck 

 

 

 

 

 

 

 

 

 

 

[Andyjr1515]

I ordered a tenor ukulele mould from Radius Dish UK - superb product but did take a long time to arrive:

 

I also ordered a sitka spruce bookmatched pair, which I planed and scraped down to a touch under 3mm and joined:

 

And also found in my small wood collection a full mahogany back and sides set - I have NO idea when and what I bought that for...but it would do nicely.

 

Again, planed and scraped the sides down, this time to around 2mm and then out came the bending hot pipe.  First a good dousing with water:

 

Then on with the leather work gloves.  With a bending iron, a hot pipe and a lot of patience plus plenty of spritzing is the key:

 

One half nearly done:

 

And now both! 

 

Once that was fully dry (overnight) I could cut the sides flush at either end and cut a mahogany tail block and neck block to glue them up:

 

Then, having found the rubber-banded clothes pegs in a long-forgotten drawer, applied the kerfed (slotted) linings:

 

And then that's the sides done ready for radius sanding    :

 

 

 

 

 

 

[Andyjr1515]

And bringing it up to the present state of play...

 

To balance the purple of the headstock and fretboard, I added a slice of purpleheart to a cut block of ebony and carved the beginnings of the bridge.  I also cut the fretboard end to where it will meet the soundhole:

 

Next, I turned my attention to the decoration around the soundhole.  Although you have to be a bit canny to maintain the accuracy, I actually find the Dremel radius accessory reasonable for this job:

 

I used a 1mm bit to cut a circle at the centre and wrapped some 1mm b/w/b purfling into it after running a teeny bead of glue onto the bottom edge. 

 

After scraping the excess purfling off, I drilled an offset radius tool spike-hole that will be used to put in a second, larger offsett ring (you can just see the pencil check marking offset and outside the installed ring):

 

And then another radius tool spike-hole in between those two to be able to cut - using a 3mm bit - a mid radius to create an offset channel for some curved abelone that, all being well, would fit in between the two other rings.  It worked!!   And finally, the radius tool spike back to the original hole, but at a slightly smaller radius to now cut right through and create the sound hole   :

 

 

And that's how far I've got so far.  It's dinky, isn't it!!!!  @Frank Blank might recognise the LAG next to it  :

 

 

 

 

 

 

 

 

[Richard R]

My grandchildren, if and when they arrive, will be lucky to get anything more than cotton-reel tanks and a pram-wheel go-cart.

[Andyjr1515]

9 minutes ago, Richard R said:

My grandchildren, if and when they arrive, will be lucky to get anything more than cotton-reel tanks and a pram-wheel go-cart.

Well, after this...nor will mine 

[ezbass]

You look away for a little while and a guitar appears from some old bits of timber that were lying around. What a talented chap you are and with very lucky grandchildren.

[MichaelDean]

This is amazing. Loving the updates!

[Geek99]

On 17/09/2023 at 16:41, Andyjr1515 said:

I've found quite a bit of stuff for it in my various bits-boxes and rubbish bits-piles.  Including - and I have NO idea why I have a set of these - some classical guitar tuners!:

 

I found a mahogany offcut from one of my bass builds.  Would the tuners fit?  Wow - clearly this was meant to be     :

 

So, after cutting a headstock angle, out came my little Proxxon pillar drill:

 

Back to the band saw to cut the rear face of the headstock, then back to the pillar drill and scroll saw to drill/saw the slots:

 

Well - that went better than I thought it would!

 

 

There’s two too many tuners. You’ll stunt their growth by making them into guitarists 

just stop at four, and make them nice big ones.
For thick strings 

chrome’s good

you could have the tuner key, shaped as … um.. maybe like an elephant ear ?  you know, just for fun

Edited September 18, 2023 by Geek99

[Matt P]

I love a tiny guitar, just had this made by a guy in Cumbria, 19" scale and baritone uke host, tuned A-A with regular acoustic strings the guitar behind is a full scale acoustic that was made at the same time. 

[Rexel Matador]

Beautiful. Definitely need to get me some purpleheart!

[Hellzero]

Following with the usual greatest interest.

[Andyjr1515]

After a few days child-minding the said special little people, I'm back in the cellar

 

For the bracing, I am using my home-made 25 foot radius dish although, for this build, will dispense with the Go-bar deck - I should be able to get away with just clamps and cauls.

The bracing pattern is going to be pretty basic X-bracing with the standard-recommended tightly vertically-grained spruce.  I've taken a bit of a guess at how much to scale them down.

I started with the X-brace with gluing the cruciform and then sanding the bottom curve on the radius dish:

 

 

This was glued to the top with a long caul keeping the curved brace bottoms pressed against the radius dish while the glue cured :

 

After that was set, it was time to add the other braces and sound bars.  All of the braces will be  chiselled to create the nodes, etc, once it has dried overnight:

 

And here it is ready for tomorrow's chisel and tap-tuning work :

[Si600]

1 hour ago, Andyjr1515 said:

...and tap-tuning work :

 

[Richard R]

I can see the bottom two braces aren't symmetrical with the centre line of the top, presumably to avoid unwanted resonances. Where to the notches go, is it all by ear or is there maths and measurement to start with?

[SamIAm]

Fascinating to watch a master at work!

S’manth x

[Andyjr1515]

46 minutes ago, Richard R said:

I can see the bottom two braces aren't symmetrical with the centre line of the top, presumably to avoid unwanted resonances. Where to the notches go, is it all by ear or is there maths and measurement to start with?

Much of the position of the notches is 'Mr Martin put them there in 1920 whatsit and it was good enough for him and so it is good enough for me'  

 

To be honest, there are certain positions and proportions, especially of the nodes, that many of the 'respected' plans share and it is said that even 5mm difference in their position will make an audible difference.  But there are actually a myriad of alternatives that will produce an acceptable result.  And this is where tap tuning comes in.  I'll try and find the Bourgeois video where their main man demonstrates what he does - and you can see and hear the difference.  I can tell when I get it right, but getting it right is usually more by accident than design. 

 

I generally start by creating nodes and tapers in the 'conventional' places and then chisel away blindly and stop when it sounds OK or starts sounding (even) worse 

 

[Andyjr1515]

2 hours ago, Richard R said:

I can see the bottom two braces aren't symmetrical with the centre line of the top, presumably to avoid unwanted resonances. Where to the notches go, is it all by ear or is there maths and measurement to start with?

There's a huge amount of detail here but, in the last third of the video, he actually goes from the un tweaked top's starting point to where the sound he is after is getting close.  I would be pleased to achieve the sound that he starts with, let alone where he finishes!

 

The basic theory is that you want the top to ring at the critical frequency somewhere on the top for every note that is going to be played up the fretboard.  So he listens for the 'drum' pitch and associated sub-harmonics for every note and, if one is missing, takes off a miniscule amount off the appropriate brace until he can hear it.

 

 

[Richard R]

Fascinating stuff! Solid body electric instruments are so much easier!

 

I remember now, the maths involved in calculating vibrations on a cylinder top/drum head/speaker cone are Bessell Functions. Which  I haven't used or needed since university 😊

 

[rubis]

Fabulous

What a lovely thing to do 

[Andyjr1515]

Well, not overly sure just how thin to make stuff, but at least this is now ringing out with sub-harmonics and definite bass /treble tap notes from the upper and lower halves respectively.  Then the linings were relieved where the main cross braces will go that will lock the main strength-critical braces to the sides:

 

Quick check fit, looking for gaps:

 

And the old adage that you can never have too many clamps

 

And tidied up:

 

Next jobs will be fitting a bridge plate, doing the first rough-fit of the neck angle and pondering on whether to add a side sound hole or not