Finished! Tom's African Build 2

[Andyjr1515]

1 hour ago, Si600 said:

How do you know how deep to cut the fret slots? Once the board is radiused isn't the middle bit of the board now cut too deeply if the sides are correct?

Yes - it's a bit iterative.

I personally cut the slots to around 4mm on a board that has been initially thicknessed to 7mm.  I then lose getting on for 1mm along the spine through the radiusing, and up to 3mm at the sides of the untampered board from the radiusing process.  Usually, this leaves the lower frets still deep enough once the board has been tapered and thus the radius effect is less.  For the upper frets though, depending on what radius is being cut, then the sides can indeed end up too shallow, so I deepen them with my fretsaw angled from the centre to the edge so that I'm only deepening where it's needed - that is a pretty quick and easy job.

If you fret once it has been glued to the neck, you can cut the slot deeper to start with, but nowadays, I fret the fretboard before gluing it to the neck and therefore need a decent amount of wood still below the slot so the board doesn't break when hammering in the frets.  Cutting an initial 4mm slot in a 7mm board blank gives me 3mm meat underneath for most of the fret slots which is usually enough.

I use a thin piece of metal with a couple of depth marks on to ensure that the slots are clear of dust and deep enough along their whole lengths before inserting each fret. 

 

[mixingwithtom]

This is all looking rather fab!!!

[GarethFlatlands]

Looking forward to the truss rod routing as that's where I hit a big of a snag on my neck build. The guide that came with my cheap (but good) router is a little flimsy and there was a bit of wander when I had a quick bash at it the other day.

[Andyjr1515]

1 hour ago, GarethFlatlands said:

Looking forward to the truss rod routing as that's where I hit a big of a snag on my neck build. The guide that came with my cheap (but good) router is a little flimsy and there was a bit of wander when I had a quick bash at it the other day.

I finally invested in a router table last year so mine will be a little more straightforward this time round.

  Up until then I did it much the same as you.  Like a lot of things, after a few goes, you start to get a feel of where and hold the router and how to keep the guide firm against the neck side.

Like all things to do with routers, I cut no more than 2mm depth at a time.

[GarethFlatlands]

Thanks, I think I'm going to build a simple jig as per this video. Looks pretty straightforward and should keep the cuts super straight.

Straight Line Router Jig

[honza992]

3 hours ago, GarethFlatlands said:

Thanks, I think I'm going to build a simple jig as per this video. Looks pretty straightforward and should keep the cuts super straight.

Straight Line Router Jig

Thanks for linking to that, I've never seen one like that before.  If I ever get a table saw I shall definitely be making one.  Simple and elegant. 

Without a table saw, the other option if you have two straightedges which are the same height is simply to tape those down onto the neck.  Use a guided router bit to run along one of them, and the other is there just for support.  Low tech, but routers naturally 'go left', so the guided bit pushes against the left hand straight edge.  Perfect straight slots (as long as you remember only to rout pushing away from you, never pulling towards, otherwise the 'left' changes sides and you slot gets wider......) The perpendicular mini straight edge is just a 'stop'.....

 

Edited February 18, 2020 by honza992

[honza992]

On 15/02/2020 at 13:07, Andyjr1515 said:

I always agonise over investments in tools and facilities, but having decided that hand radiusing hardwood fretboards is the road to insanity, I built myself a radiusing jig a few years ago.  

While it worked well, it was a bit inconsistent and quite difficult to setup.  So last year I bit the bullet and went for the G&W (Guitar & Woods) unit with a couple of extra radii formers.  And boy, am I glad I did!  It does the job quickly and efficiently - but more to the point, accurately.


 

Jig GAS!!  Nice.......

[honza992]

On 14/02/2020 at 18:01, Andyjr1515 said:

 

 

 

 

 

 

 

 

Fanned frets is on my list of challenges.....it looks like you've got the perpendicular fret at about 11 or 12?  Can I ask how you decided to put it there?

[Andyjr1515]

2 hours ago, honza992 said:

Fanned frets is on my list of challenges.....it looks like you've got the perpendicular fret at about 11 or 12?  Can I ask how you decided to put it there?

It's the 'usual' arrangement where the fan is equal between the nut and the bridge - same angle but mirrored.  On that basis, where the angle changes from +ve to -ve will be in the middle of the scale, ie the 12th fret.

But it doesn't need to be.  You can start a more acute or less acute angle at the nut and adjust the angle at the bridge accordingly.

Edited February 18, 2020 by Andyjr1515

[Stub Mandrel]

20 hours ago, Andyjr1515 said:

It's the 'usual' arrangement where the fan is equal between the nut and the bridge - same angle but mirrored.  On that basis, where the angle changes from +ve to -ve will be in the middle of the scale, ie the 12th fret.

But it doesn't need to be.  You can start a more acute or less acute angle at the nut and adjust the angle at the bridge accordingly.

Don't all the fret lines converge at a common point?

[Richard R]

41 minutes ago, Stub Mandrel said:

Don't all the fret lines converge at a common point?

Yes, 12th fret on the high C string

[Andyjr1515]

This probably illustrates it more clearly?  :

The fret positions for each string is fixed mathematically, appropriate to each scale - in this example, the G at 31", the E at 33" and the other two strings at their respective intermediate scales.

 

But where the E scale and the G scale start and end is up to the builder.

They could both start at the same place at the nut (top example) and the whole 2" difference will be seen at the saddles

Or the G could start 1" inset at the nut, (like the middle example), which will mean that the saddle will be 1" inset too

Or the saddles could start in the same place at the saddles (like the bottom example) and so the whole 2" difference taken at the nut 

Or multiple combinations in between or beyond!

 

 

 In the case of Pete's Piccolo, I decided to have the nut almost perpendicular and take the bulk of the offset at the saddles:

 

And so the slant of the lower frets was pretty modest but it gets steeper the further up the scale you went.  In this case, the perpendicular fret was probably the 2nd fret.  But it was only a 1" difference between the E scale and the G scale so the angle at the upper frets and saddles were still acceptable.  The E saddle is pretty much 1" further to the back than the G saddle, representing the two scale lengths.  Doing it like this, most of the frets are angled in the same direction.

In Tom's case, I have a 2" scale difference so if I had made the nut perpendicular, then the upper frets and saddles would be very angled indeed.  So I decided to position the G string nut such that I would have the same angle at the nut as at the bridge, albeit in opposite directions.  To do this, I positioned the G string nut 1" towards the tailstock compared with the nut position for the E.  The bridge saddles line isn't marked here, but it will be the same angle as the nut, albeit in the opposite direction, with the G saddle being 1" offset towards the headstock compared with the E saddle.  So here there is an angle change and - where the change happens is the mid point, which is at the 12th fret in both cases:

 

For someone who likes building necks and fretboards there could be many a happy hour making all the variations to see which felt best to the player or which gave advantages or disadvantages relating to pickup positioning.  Happily, that someone won't be me

 

 

Edited February 19, 2020 by Andyjr1515

[Andyjr1515]

Tom has some Hipshot tuners and their new screw-adjust single saddles on order.

In the meantime, I've started on the neck and fretboard.

After lots of checking, and double checking and triple checking, the fretboard has been tapered and the neck blank cut to length and headstock angle cut:

 

Next job - while all of the straight sides are still there, it to route the truss-rod slot and then I can start cutting the neck profiles and heel cutouts

[Andyjr1515]

Trussrod slot cut and headstock plate area flattened.

The angle of cutaway at the nut makes it look like the headstock is going to be at an angle to the fretboard - but that is just an optical illusion - it is parallel to the top of the neck.

The headstock plate itself will be 1.5mm wenge constructional veneer as will be the pickup rings.

Last thing before bandsawing the neck outline shape is to cut the body joint.  Quadruple checking before I do that!!!

 

 

Edited February 22, 2020 by Andyjr1515

[Andyjr1515]

After the quadruple checking, I marked up the neck pocket to start the initial hog-out and rout.

The first step serves a second purpose - what are the properties of this unknown wood species?  The last African Bass gave some challenges - and this is the same species, albeit a different cut.

I hogged out with one of my best Forstner bits - a Fisch Wave Cutter.  Quite expensive but stupendous bits if you want to minimise cutting issues.  The wood was, as I expected, very hard - the hardest wood I think I have dealt with (yes - harder than ebony in my experience) and quite brittle.  It doesn't matter because in both cases these are going to be cut away, but pinged some bits despite some very careful and steady cutting:

 

But that answered me a question.  Based on the grain pattern in this area, as you see below radiating from the centre of a knot, I might have to rethink the best way to attach the neck:

 

I used a chisel to straighten the sides and then a teeny bearing flush bit to rout down to the planned depth:

 

And then had a look and a think.  My concern is that, to do the original plan means I need to cut the pocket even shorter to square it up for the neck heel to butt up against:

That's a lot of useful length to lose when the pocket base is quite thin and potentially very brittle - especially if I'm going to cut a biscuit slot in it as well!

So I've decided to leave the body heel where it is and use a cut-away neck plate (like this one I did recently on @scrumpymike 's Rascal):

 

With that decided, I could cut the neck blank.  There is no heel as such, the whole blank up to the volute is cut at 15mm which will give me a maximum neck thickness of around 22mm.

 

And it will look something like this:

 

 

Edited February 23, 2020 by Andyjr1515

[SpondonBassed]

Looking at the grain that you revealed in the floor of the neck pocket; I wonder if it might be prudent to bond some sort of reinforcing layer to the neck pocket.  This would be like a shim except that it is bonded to the parent body to prevent microfractures from joining up and causing problems down the line.

When you hear musicians talk about breaking in a new stringed instrument they sometimes speak of the wood grain "opening up".  This is said to add to the instrument's characteristic tone and possibly to its individuality of tone.

While I don't fully understand what goes on, I'd guess that vibrations in the wood (from the strings) act over time to resolve stresses within the wood by causing microfractures.  I'd expect all wooden instruments to be subject to this phenomenon (if it exists) but some might be more prone to suffer damage from it.

Then again, I may just be making it all up...

[Andyjr1515]

3 minutes ago, SpondonBassed said:

Looking at the grain that you revealed in the floor of the neck pocket; I wonder if it might be prudent to bond some sort of reinforcing layer to the neck pocket.  This would be like a shim except that it is bonded to the parent body to prevent microfractures from joining up and causing problems down the line.

When you hear musicians talk about breaking in a new stringed instrument they sometimes speak of the wood grain "opening up".  This is said to add to the instrument's characteristic tone and possibly to its individuality of tone.

While I don't fully understand what goes on, I'd guess that vibrations in the wood (from the strings) act over time to resolve stresses within the wood by causing microfractures.  I'd expect all wooden instruments to be subject to this phenomenon (if it exists) but some might be more prone to suffer damage from it.

Then again, I may just be making it all up...

For the same reason, I am actually contemplating a variation on that theme

[Si600]

Dunk the whole thing in resin. It seems to be fashionable. On YouTube at least. 😉

[Andyjr1515]

Excepting a small triangular needle file that I draw along the slots to relieve the sharp edges, this is pretty much my whole fretting equipment:

The de-nibber is one of those tools that, once I got one, I couldn't imagine how I could do it without!  Worth every penny.

In terms of method, I :

- de-tang one end of the wire

- measure from where that end will position in the slot to the edge of other end of the fretboard

- detang there

- cut the de-tanged notch at the middle and I have my fret, de-tanged at both ends

- run a teeny bead of Titebond along the tangs

- place it in the slot, hammer one end, hammer the other end, hammer the middle to spread the tang barbs under the wood

- wipe the glue squeeze-out with a dampened cloth

- clamp a radius block over it 

- move to the next slot and repeat.

 

Once dry, I trim the overhanging ends, then sand the remaining overhang by drawing each side along my emery-papered levelling beam.  Then I tilt the board 45 degrees on the beam to create the bevel.

And here we have a fretted board ready for fitting at the appropriate time

 

[SpondonBassed]

1 hour ago, Andyjr1515 said:

The de-nibber is one of those tools that, once I got one, I couldn't imagine how I could do it without!

Is that the thing that looks like a school compass?  What's it for please?

[Stub Mandrel]

2 hours ago, SpondonBassed said:

Is that the thing that looks like a school compass?  What's it for please?

De-nibbing.

As any fule kno.

[Andyjr1515]

3 hours ago, SpondonBassed said:

Is that the thing that looks like a school compass?  What's it for please?

I sometimes get my nibs mixed up with my tangs.  But I'll take a photo tomorrow to show what it does, whatever it's called! 

[Andyjr1515]

Tang nipper, tang nibbler.  I'm going to call mine Bert.  Easier to remember.

[SpondonBassed]

19 minutes ago, Andyjr1515 said:

I sometimes get my nibs mixed up with my tangs.

Yet it doesn't show up in your gait.

Edited February 27, 2020 by SpondonBassed

[Andyjr1515]

Ref @SpondonBassed 's query, the fret tang nibbler/nipper is like a mini punch tool.

The fretwire slots into the shaped die:

 

 

 

Firm squeeze and your tang is well and truly nibbled (now then, John!  Keep it clean!  )

 

Cut in the middle and you have a fret where the tang won't end up as the irritating sharp bit as the neck and fretboard progressively settle down after assembly and finishing:

 

And that gives a sneak preview of the inserts I've just fitted to the neck:

 

I normally use M4 (4mm) machine screws but for this one, because I want maximum clamping on the unknown timber neck pocket floor, I'm using M5 screws:

When I tidy up the body carve, I will make the pocket run parallel with the curve of the plate - it will take very little off the area of the pocket but will make it look like it was always meant to be attached like that

So I'm pretty sure I can fit the trussrod and glue the fretboard...

...and it's tipping it down so no chance of any useful outdoor domestic stuff just at the moment