Yew-topped SG-style Guitar * Finished Pics!

[Andyjr1515]

Yesterday was a bit of a lazy day so I got cracking again today.
First job was to glue on the headstock plate:


That meant that I could confirm the final positioning of the neck and therefore also the pickup chambers.

Those who have watched my build threads know that I hate routers.  I will use them, but only where they are pretty much the only thing for the job.  In terms of pickup chambers, that in my book is one small job.
For what it's worth, this is how I do them.  Having worked out exactly where they are going to be, I draw out the chamber outlines.  Then I drill the 8 corners:


Then, I hog out to the edges with a large forstner bit and use a chisel to take me up to the pencil line to a depth of around 10mm:


And then, and only then, I use a bearing trimmer bit in the router to tidy up the sides and get it to final depth:

You can just see in the above shot that I have successfully intersected the cable run channel that I cut before gluing the top - phew!

And then repeated the whole thing for the neck chamber:


Still no trussrod.  May need to order another one from a different supplier...

[Andyjr1515]

The last structural job on the body will be to rout the control chamber to final depth and to rout the recess for the hatch.  But before I do that, there's a bit of structural integrity to sort out.

Knots - they can add beauty, especially to Yew - because the wood grain sweeps round what are emerging branches.  But that is what they are - and so knots are always effectively separate parts of the wood and so have to be stabilised.

So, today's scary picture to those who haven't got up close and personal to these kind of woods   :  

And there's a related crack that goes all the way towards the pickup chambers.  So my strategy is to stabilise and do the bulk filling at the same time.

First step, I have 'wick'd' thin superglue into the cracks.  Capillary action sucks the cyano deep into the crack which will help reduce future movement:

 Then - goodness, has this build turned Andyjr1515 to drugs??????


No - at least not yet .  It's a syringe folks use to get medicines down cats and dogs throats.  And perfect for forcing epoxy&wood dust mix deep into the larger fissures.  Yes - I know what it looks like... 


And all done waiting cure and sanding:


And after that, finishing off the control chamber.

[Andyjr1515]

I reckon that's enough for today.

I've got most of the cyano and epoxy overfill off the top:


...and routed the control chamber to depth:


The observant amongst you will have spotted the pickup cable channel in the side wall.
Depending if the truss rod arrives or not tomorrow, then I will probably complete the carve, adding the rear cutaways, etc, and rounding some of the hard corners.

As always, thanks for looking and for the encouraging feedback, folks

[Andyjr1515]

I've cut a slice off some Sapele offcut to use as the control hatch.  I generally use a bottom-bearing rebate bit to cut the rebate and then just square off the magnet-protrusion peaks you can see here with a chisel.  The little offcut is to double make sure that the rebate is the correct depth before I put the router away:


And then I started the carve at the back.  Although I don't think the 'proper' SG's have wing cutaway relief at the back, that has always seemed daft to me as it is one of the things that makes it much easier to get to the upper frets.  So this one's got them   This is after the 'reveal & seal' coat of Tru-oil prior to final sanding:


Why do I call it the reveal and seal coat?  Well, the seal I've talked about before - I do a light slurry-and-buff with Tru-oil as an initial grain-fill and sealer step even when, like this one, I'm going to eventually gloss varnish it.

But it is also, I find, the very best way of finding missed dints, sanding marks, glue spots and other similar things to tidy up.

Take, for example the edge here - I can now see that the edge needs a little more cabinet-scraping work to ensure that the demarcation line is revealed all the way round:


And here, you can see that again and also some glue spots that need sanding away:

As always, thanks for looking 
 - and stay safe

Andy 

[TheGreek]

Learnt yesterday that the pronunciation is Sa-pea-lay...

Goes without saying but I will anyway...good work Andrew...

[Andyjr1515]

In terms of cleaning up the edges, this is closer to how it should be with the demarcation stripe fully visible:

The fretboard isn't fixed yet - I have a feeling the truss rod's not going to arrive anytime soon so I've ordered a second one from a different supplier.  If/when the original one arrives, it'll just go in my bits box ready for the next build

[BassTool]

Lovely, lovely, lovely.

Great work and great pics 👍🏼

[Owen]

Yew is what the cool kids are using

[SpondonBassed]

52 minutes ago, owen said:

Yew is what the cool kids are using yewsing.

Ahem.

 

 

 

Heeheehee

 

 

 

That's an extraordinary guitar with the void like that.

[Andyjr1515]

1 hour ago, SpondonBassed said:

That's an extraordinary guitar with the void like that.

It's what mine might look like if the router slips when I'm sorting the controls

[scrumpymike]

It's very, errr, relic'd-organic, which obviously makes it highly sought-after.

[RichardH]

Here's the only thing I've done with yew - we had a tree cut down in our garden, and this slice was too good to waste....

[Andyjr1515]

Well yesterday, the truss-rod shipped on 24 hour service last week arrived (not a grumble - just a fact of life at the moment).  But, actually, I'm pleased that I ordered a second one (which arrived today), because while the original purchase was very nicely made (the one with the fancy chrome end) it is no good for me on this build:


And why is it no good for this build?
  
Well, remembering that the rod is fitted the other way up, the fancy chrome cylinder (inside is probably exactly the same gauges of rod and tip as the one on the left) actually adds another 2mm to the depth of the neck channel - just at the point where the neck is at its thinnest.  And if you add the fret height to the fretboard thickness and the rod & tip height (11mm) and take away the planned thickness of the neck at the 1st fret (22mm), it would leave 2mm under the rod at the nut end.  And that's not, IMHO, enough.

Same calculation with the left hand trussrod, gives me 4mm under the rod - and that is fine.  So that's what I've used.

Is that going to be a problem for everyone with that particular rod?  No - not at all.  If the fretboard had been thicknessed 1.5mm thinner and I hadn't wanted the 0.6mm demarcation veneer, then it would have been fine.

But, ignoring all that, it means that the fretboard can go on

No capping strip (again, this would reduce the meat under the rod), just a strip of masking tape to stop the glue filling the channel, a final check that the neck was flat and that the rod top plate was flush with or below the neck glue face:

And...it's on:

[Richard R]

Dumb question:

Is a truss rod fixed into the groove in any way? If it's just loose on the slot then I can't see how it would do the job, as it would just slop about, but no build ever mentions "bond the truss rod into the groove".

 

[Andyjr1515]

39 minutes ago, Richard R said:

Dumb question:

Is a truss rod fixed into the groove in any way? If it's just loose on the slot then I can't see how it would do the job, as it would just slop about, but no build ever mentions "bond the truss rod into the groove".

 

Not at all a dumb question.

Some people do pop a few dollops of flexible sealer in to stop the possibility of a rod rattling.  I myself used to wind plumbers PTFE tape loosely round the whole thing for much the same reason. 

But nowadays I don't bother.  The way I do them, width-wise, they are a tight fit in the slot. Depthwise, I make sure that - when flat - the metal plate of the rod is either flush with the top of the neck or I use a packing strip on top.  Either way, there is already pretty much zero gap between the rod and wood.  Then, when it is in use at all, it is flexed against wood at both the middle and both ends -  and my logic is that if it still rattles then there is something seriously wrong and a rattle from the rod is the least of your worries 

A trick - for where the neck is 'naturally' back bowed and therefore the trussrod is actually not needed and left basically loose, is to tweak the adjuster until a tiny bit of resistance is felt.  That means the rod is now pressing lightly against the top and bottom of the slot and this should usually eliminate any possibility of rattle even though it isn't exerting enough pressure to impact on the neck relief.

[Andyjr1515]

Clamps are off.  Couldn't resist doing a quick mock-up

One of the good things about lockdown is that you know exactly what you are doing the next few weeks.

So I know that tomorrow, I'm going to be carving the neck  

[SpondonBassed]

1 hour ago, Richard R said:

Excellent Dumb question:

Is a truss rod fixed into the groove in any way? If it's just loose on the slot then I can't see how it would do the job, as it would just slop about, but no build ever mentions "bond the truss rod into the groove".

 

How does the rod exert a force on the neck though?  I imagine it to be secured at one end and that the bit you turn acts like tightening a bolt...

I've never actually seen the end secured however.  Is there a little tee slot or something?

Edited April 23, 2020 by SpondonBassed

[Si600]

And why doesn't it pop the fretboard off?

[Andyjr1515]

6 minutes ago, Si600 said:

And why doesn't it pop the fretboard off?

Because, happily, the neck bends

[Andyjr1515]

50 minutes ago, SpondonBassed said:

How does the rod exert a force on the neck though?  I imagine it to be secured at one end and that the bit you turn acts like tightening a bolt...

I've never actually seen the end secured however.  Is there a little tee slot or something?

Think straight rod sitting in a slot the exact same size, no glue but it can't go anywhere because there's the sides of the neck either side, there's the purple-heart neck splice underneath and there's the fretboard on top.  It is the length of the neck from heel to nut.

The strings are trying to pull the neck, and therefore the slot and rod into a U shape from the heel to the nut.  Tensioning the trussrod arches the rod in the middle (12th fret ish) and by newton's law, applies equal and opposite force on the purpleheart strip at either end of the rod (at the heel and at the nut) as it forces the neck from U back to straight.  And if you then loosened the strings, it would bend itself and the neck with it into a 'back bow' arch shape.

Easier with a picture but that means I have to remember how to draw curves properly...

[SpondonBassed]

Okay, so it's in compression rather than tension but what is it actually bearing against?  Is there a shoulder?

I mean, you have to access the end of the rod with whatever adjustment tool it requires...

[Andyjr1515]

This is probably a bit clearer, @SpondonBassed  

This is how the truss rod is in its un tensioned state.  The LHS would be at the heel and the RHS at the nut:

 

And this is what the unrestrained rod is trying to do when it's tensioned:

So it's trying to bend down and take the neck with it.

But the string tension is trying to pull the neck in an opposite curve so the result is that the rod (and therefore neck) ends up straight.  But the forces at the top and bottom of the slot are downwards at either end and upwards in the middle.

The heel means that the left hand end is secure, but the danger is, as @Si600 says, if the glue joint isn't good for the fretboard, it can force the fretboard off from the middle, and if there isn't enough meat under the rod at the nut end, the rod can burst through the bottom of the neck.

[Andyjr1515]

2 minutes ago, SpondonBassed said:

Okay, so it's in compression rather than tension but what is it actually bearing against?  Is there a shoulder?

I mean, you have to access the end of the rod with whatever adjustment tool it requires...

No it's not anchored (there is an end stop effectively where the slot ends at the heel-end) other than the force of the bend of the rod itself.  In fact, if you get your slot right and keep glue out of it (and you'd need to take the headstock plate off too) you can make it so that the trussrod can be pulled out for replacement.  I think the earlier Warwicks were like that?

[Maude]

Inside the trussrod assembly there is a threaded bar that has two opposing threads, right hand thread at one end and left hand at the other. There are two fixed threaded tubes, nuts if you like, at either end, so as you turn the threaded bar via the allen key, the opposing threads either pull the ends of the rod together curving it one way, or push them apart, curving it the other way. 

Edit, I should add that the above is a dual action rod. A single action is just a threaded bar which is fixed at one end and passes through a non threaded sleeve at the other, adjusting end. A nut is placed on the threaded bar outside of the non threaded sleeve and when tightened creates tension in the trussrod assembly making it bow. 

Edited April 24, 2020 by Maude
Adding single action

[Andyjr1515]

Most builders will tell you that their favourite part of a build is carving the neck.  It certainly is mine

The first thing I usually do is rasp-file the corners off the volute:


...which lets me go the full length heel to headstock in continuous strokes of the spokeshave:

You do have to be careful with the spokeshave, though.  I've gone from rectangular to broad curve on this side in just over 1.5 minutes!  It would be very, very easy to overdo it!
In all cases, though, I am moving progressively round from fretboard edge to the edge of the purpleheart and so taking nothing off the thickness of the neck, just removing material from the haunches.

In less than 10 minutes total, I move across to a fairly fine microplane.  In use, I hold either end and draw it up the neck just like a spokeshave - but trying to show that would mean me dropping the camera!

You can see how quickly the basic shape starts getting there.  However, I do stop frequently, have a cup of tea, play a bit of air guitar on it and view the shape from afresh to work out where I need to spend some more time.
Normally, I would move onto the cabinet scraper pretty quickly (again, drawn up the neck two-handed) but mahogany is quite soft and doesn't respond so well to a scraper used hard - so for mahogany I tend to stick with the micro-plane and then use the scraper just to 'kiss' the sides rather than bulk-remove material:

 

This is about 1 1/2 hours in, including the tea breaks.  I'll come back to it this afternoon and the carve should be complete by the end of the day: