Finished! A Guitar Bouzouki - (no basses were harmed in the...)

[Richard R]

15 hours ago, Andyjr1515 said:

long reach calliper

You mean "Linda" 😉

[Andyjr1515]

1 hour ago, Richard R said:

Now THAT is the word for the weekend! Especially if playing scrabble. 

More seriously, when you say it "rings like a bell", do you hold it by a corner and tap it? What happens if it goes "donk" at this stage?

Yes.  I'll go into the black art of tap tuning when the braces have been put on, but yes - you do just that.

If it just goes "donk" and it is tight-grained quarter-sawn spruce, then is usually means it's too thick.  If it just goes "donk" and is tight grained, quarter sawn but not spruce or cedar or mahogany, then it probably isn't the right wood.

I'll go into more detail later, but basically, you need the top (which is where most of the tone comes from) to resonate somewhere to every note that will be played.  So once it is braced, you are trying to hear - either at the base pitch (like tuning a drum skin) or as a harmonic - every note when the top is held from different edges and tapped in different places.  It bodes well when the unbraced wood is already giving out a distinct set of base drum notes but also multiple ringing harmonics at every tap.

When we get to the tap tuning, I'll post a fantastic video of a top builder doing and demonstrating this to an audience before their (and our) very eyes.  It makes you a much more discerning buyer of acoustic guitars! 

Edited June 20, 2020 by Andyjr1515

[Richard R]

Thanks for that. Look forward to the video - especially as when we are eventually allowed out of our bubbles my son wants me to accompany him to buy an acoustic guitar 👍

[Andyjr1515]

So - rosette time.

This is the design that P and I have settled on - the outers will be black/white/black purfling, the inner will be back/side offcut wood, the swift will be MoP

It's always a risk to show how I'm going about it before it's done...because this, of course, may not work

But this is Andyjr1515!   As one of my fellow band members once said (about my playing, but my building is much the same) "what I like, is that you're always on the very edge of disaster!"

He then, of course, went through all the stuff he didn't like 

So I had a ponder and, although on the face of it, this makes no sense, I think it might work.  This is my main kit (plus a Dremel):

 

After using the compasses to pencil out the shape and verify the centre points, I drilled those centers for the spike of the Dremel radius tool to go into.  Then routed the curves for the purfling up to the tangent points:

 

Happy monkey! 

 

Then used a straight edge to join the curves up:

 

And eventually ended up with this:

 

The slightly Andyjr1515 thing is that I'm going to put the purfling in and then rout out the area between it.  And I'm then going to cut some back wood and fit it as I would a control cover.  We'll soon see if that is a decent idea or a really, really, really bad idea

Anyway, this is broadly how the top is going to look:

 

And this is how the now-joined-but-not-yet-thicknessed back is looking:

Tomorrow, I'll bend and fit the purfling and then see if I can rout the bit in between 

 

 

 

Edited June 21, 2020 by Andyjr1515

[Si600]

I R confuddled.

Purfling? What, how, where and other adjectives.  You've lost me on the plectrum shaped sound hole and what colour, or even what component goes where.

[Andyjr1515]

1 hour ago, Si600 said:

I R confuddled.

Purfling? What, how, where and other adjectives.  You've lost me on the plectrum shaped sound hole and what colour, or even what component goes where.

I are confuddled too - because I've just thought of a MUCH better sequence of inset wood in between said purfling

Purfling's this:

 

You can use it as a feature line by itself, like the outer ring, or as a boundary, like the inner rings:

 

Or you can use purfling as an inner addition to binding which is on the outside of the side corners:

 

 

 

 

[Andyjr1515]

And that's quite a good picture to use - so P's rosette will be (assuming I don't c**k it up!) like a triangular version of this:

So my revised method (unless I have another after-thought) will be :

-  Rout the area that the back wood and swift logo is going to go in

- cut the back wood, slightly oversize

- re-route the purfling slots at the join between the top and back wood.

It'll make more sense when I do it...

 

… I promise 

 

[Andyjr1515]

So first thing was to take a thumbnail impression of the shape:

 

From which I could choose a suitable piece of bookmatched back/side wood.  Next was to rout out between the two purfling lines:

And then - carefully, because it is very, very brittle at those sharp ends - sand 'fit' the inset to the chamber:

Once that was sanded it to fit, it was glue and clamp:

When this is fully dry, I will plane / sand it level and then re-cut the purfling strips.

 

In the meantime, I made a start on the body mould.  It will be a simple affair - two matching plywood shapes that will be separated by a series of wooden blocks for each side and held together with steel screw joiners.  First task was to cut the four plywood sides:

It's not fragile - it's plywood.  Just in these times of lockdown, I've run out of my normal packing tape to hold the pieces together!  

 

 

[Andyjr1515]

And the purfling is in:

Bit of domestic duty stuff to do today, but later on should be able to get the swift inlay done and then the sound hole can be cut out using the same Dremel radius tool from the same centre holes to get nice concentric curves.

Also today, I'll be ordering the woods for the bracing, kerfed strip (don't worry @Si600 - I'll explain ) and so on.

 

[Maude]

It looks a very fiddly job, but looks great 👍. 

[SpondonBassed]

I'm not sure whether I prefer a kerfing to a firkin...

[Andyjr1515]

And so to the inlay.  Normal stuff - MoP cut out with a jewellers saw, then the outline of the inlay penciled onto the wood and routed out with the Dremel and precision router base and 1mm bit:

 

Glued in with some epoxy mixed with the same wood sawdust to create a colour matched glue:

 

 

And once that has dried, a quick sand and we have a swift   There's a bit of tidying up around the purfling to do, but I will do that prior to the final sanding once the braces are all fitted.

 

Tomorrow, I will cut out the sound hole and the outer shape, including a few mm oversize and then it's just waiting the dishing, bracing and tap tuning (oh, and the sides, and the back and the back dishing and bracing and the binding and outer purfling and the neck and the bridge and the...… ) 

 

 

[TwoTimesBass]

12 hours ago, SpondonBassed said:

I'm not sure whether I prefer a kerfing to a firkin...

Looking at the shape, more like a merkin... ☺️

[Andyjr1515]

18 hours ago, TwoTimesBass said:

Looking at the shape, more like a merkin... ☺️

You know no one's going to admit they know what one of those is               Oh....BLAST!!!!

 

So all needs tidying up, but we have a soundhole

 

And to the body mould.  Trying to keep all of this upright and square, you have to admire those Stonehenge dudes! :

 

Top on and inner uprights ready to fit:

 

[Andyjr1515]

And the mould is done!  Or is it mold?

Anyway, it's done:

And what is this for?

It will act as a bit of a multi-functional jig.

The first thing I will use it for is to help in bending the sides.  I will be using a bending iron to hand bend the sides and will use this initially as a guide for me to check where and how much to bend, and then once each is basically bent, I will clamp the side in this while it dries and cools and this will help it to retain its shape.

But I will also use it to hold the sides when the tail block and heel block are being glued and also the kerfing around the two edges - again helping to keep the shape accurate while all sorts of things are being done to the woods within... 

 

Edited June 24, 2020 by Andyjr1515

[Richard R]

1 hour ago, Andyjr1515 said:

And the mould is done!  Or is it mold?

Mould. Mold is for TalkBass.

Either way its very impressive!

[HazBeen]

I am loving this!

[Andyjr1515]

Thanks, folks

This morning, I cut out the top, around 10mm oversize all round at this stage.  I know it's small beginnings, but this - to me at least - is very pleasing:

 

So next jobs, while I'm sourcing the bracing woods, is preparing to bend the sides.  But first, I have to cut them to shape (a LOT easier than trying to cut them once they have been bent - and don't ask me how I know!).

Basically, the sides themselves will reduce from around 95mm deep at the heel to around 80mm at the neck.  But - that's not a straight line.  Because of the waist, the back side of the side piece does a double elongates s-curve  - and where and how much that is depends on the waist shape.  Now, I'm sure a decent CAD package (or a cheap one with a decent operator) could sort it out in minutes.  But I use CAD so infrequently, it would take me as long to work out how to do it than just cut a cartridge-paper template, put it into the mould and eyeball it (you look at the mould from the side and mark a straight line in dots from one end of the paper to the other and, when you stretch it out again and join up the dots, it will be - miraculously - the correct stretched out S you want.

Pictures will make that easier to explain.  I'll photograph it as I do it

 

 

[MacDaddy]

following this, while quietly emitting such exclamations as 'wow!', 'what the...!?', and 'how... ?'

[Andyjr1515]

And so to the shape of the sides blank.

Normal warning as with all my threads - I describe what I do and why...but never assume this is how or the best way it should be done

I start off with a rectangular sheet of cartridge paper taped so that it follows the outer shape of one of the sides in the mould.  The bottom edge represents where the top will be and the top edge where the bouzouki back will be:

 

So eyeballed edge on, this is how it looks:

In broad terms (there are foibles I'll cover in later posts), edge on like this, we will want the back to go from 105mm (plus the top and back at 5mm total will give a final tail end depth of 110mm) to 85mm at the heel (total heel depth ending at 90mm) in roughly a straight line.

So what I do is mark the 105 at the back and 85 at the front, and pack up a straight edge to that angle:

 

I then run a metal ruler at 90 degrees to and along the top of the beam and mark spots on the paper all the way from the tail to the heel:

 

So I then end up with a series of dots all the way along the paper which I join up and then cut out with scissors.

And, although this is not perfect, it is close enough to be able to use as the basis of fitting the back at the appropriate time:

 

And stretched out, you can seen that this is a million miles away from a straight line between the two points:

And - although it is very subtle, I can see the concave curve at the heel end, changing to a convex curve at just under halfway - which makes me think that my attempt is at least in the right ball-park

So next job is thicknessing the sides to 1.9mm and then cutting them to this shape - and then the scary bending can begin

 

 

[Si600]

Was Mrs Jr1515 out today, or does she know you're in danger of scratching the best dining table?

[Richard R]

7 minutes ago, Si600 said:

Was Mrs Jr1515 out today, or does she know you're in danger of scratching the best dining table?

He's probably capable of making an invisible repair if he did!

[Andyjr1515]

54 minutes ago, Si600 said:

Was Mrs Jr1515 out today, or does she know you're in danger of scratching the best dining table?

No scratches!  (and temporarily distracted) 

 

[SpondonBassed]

19 hours ago, Richard R said:

He's probably capable of making an invisible repair if he did!

I don't think even Andy could repair the damage after she rips him a new sound hole.

Edited June 26, 2020 by SpondonBassed

[Andyjr1515]

It's one of the funny things about guitar building that those jobs that are seen as impressive progress (such as carving a neck) are surprisingly quick to do.  On the other hand, planning, scraping and sanding two sides down from 4mm to 2mm...hmmm.

But it has to be done.  And next time, I must try and remember what I have found to be the easiest way 

This time round I must have used most of the tools in my workshop!  I started off with my No.5 Bailey plane:

But that was too hard, especially for the other half that needed to be planed in the opposite direction

Then I tried scapers - no - and my Stanley scraper plane - no - and even my spokeshave - better than expected but...er...no

And then ended with a plane that is not supposed to be any good for this kind of job - my block plane.  Perfect!   Just have to remember again next time.

Off and on - admittedly with multiple breaks due to the unusual heat - this took me most of the day.  But at last, it was done and the pieces cut in line with the cartridge paper template:

So next scary job - one for tomorrow -  is to see how well this timber bends