An acoustic for my nephew.

[ScottR]

On 1/25/2022 at 3:18 AM, Andyjr1515 said:

Or paraphrasing @Gogzs comment above, "I do build acoustics, but the level of craftsmanship in this thread is truly inspiring.  Thanks for that, can't wait to see the rest."

 

Hell, the level of craftsmanship in the work aids, jigs and templates is stunning. The finished piece wouldn't dare be less than stellar!

SR

[Dave Higham]

On 1/26/2022 at 10:57 AM, Gogzs said:

I assume the guitar is on a rotating stand or just fixed on a sled you were sliding freehand around?

Yes @Gogzs the guitar is on a sort of cradle and the sanding contraption moves round it. I have an off-cut of melamine surfaced kitchen worktop which is nice and flat and smooth and I did it on that.

[Dave Higham]

Well, so far so good, in fact better than I expected. I now needed to make a template for the armrest veneer. I use this spray adhesive quite a lot. When it’s dry you can stick the paper to the wood and peel it off later.

Which I did, and then stuck it to a piece of thin card.

I cut it out leaving about 3mm to trim off later.

I then had to find a piece of walnut big enough to cover the armrest. If I hadn’t already cut up the off-cuts from the back to use as a head stock back-strap I could have had a piece whose grain almost matched the curve of the armrest. In the end I managed to find two pieces to glue together which I thought should look OK. I glued them together and reduced the thickness to about 1.25mm (0.050”). When I cut the profile I thought I’d better err on the safe side so I added another 3mm all round.

As it was more or less cross-grained it was quite flexible. I glued it on using fish glue and rather a lot of tape. I was thinking I should have tried to find an old inner tube to make an endless rubber band to hold the veneer on while gluing, but perhaps inner tubes aren’t easy to find these days.

When I finally got all that tape off it looked like this.

And after some VERY slow and careful work with a spokeshave and scraper, it looked like this. I realised that, when cutting the 45° bevel, I should have taken it nearer to the purfling on the top (i.e. taken more off the extra top binding) as the 50 thou veneer when trimmed at 45° leaves a surface 70 thou wide. Still, I was rather pleased with it as a first attempt.

I then glued in the back bindings (profiled bindings are great!) and it’s starting to look like a guitar.

[Bizman62]

58 minutes ago, Dave Higham said:

I was thinking I should have tried to find an old inner tube to make an endless rubber band to hold the veneer on while gluing, but perhaps inner tubes aren’t easy to find these days.

Bungee cord is also good, it's widely available at hardware stores in various thicknesses. I got some nice lengths from a patio recliner whose canvas was broken. Agreed, it's not as tacky as bare rubber but the wowen cover still holds quite well. Surgical tube is another good option.

[Andyjr1515]

Very nice

Bicycle inner tubes are still widely available.  However - and I know I'm odd - nowadays I iron on wooden bindings in the same way I have always applied veneer (PVAwood glue both sides, let dry, ironed on). 

I can't stand the uncertainty of a bound approach and have never had a fully satisfactory result.  With the iron-on technique you know immediately whether it's right or not and - if it's not - can correct it there and then. 

But yes - I am odd like that

  

[Dave Higham]

On 1/31/2022 at 1:22 PM, Andyjr1515 said:

(PVAwood glue both sides, let dry, ironed on). 

I know this technique is used for arm-bevel veneers but haven't tried it. Do you  have to hold the veneer in place until it cools sufficiently to prevent it springing off, For binding, I've always taped it in place with gaps between the pieces of tape and a drop of water-thin CA in each gap. I also push the binding into the ledge as each drop of glue is applied. Then the tape is taken off and the whole thing flooded with CA. Seems to work OK.

[Dave Higham]

With the box closed it’s time to start on the neck. Here’s a mahogany neck blank with

two strategically placed holes drilled in it for dowel pins, and a piece sawn off it.

Moved the sawn-off piece round the back, inserted the dowel pins and glued it back together. I realise that this makes it the equivalent of a one-piece, Gibson-type neck, but it’s easier than a scarf joint.

Then planed the headstock down to the nut line.

Cut two pieces off the other end to form a heel block and thinned one of them down.

Glued the two pieces together and drilled the counter-bored hole for the neck angle adjusting screw. It would be difficult or even impossible to drill the hole after the heel block is glued to the neck shaft.

Also cut two slots and glued two cross grained pieces of maple in them so that the barrel bolt anchoring the neck won’t be pulling on end grain. In fact, there needn’t be much tension on the barrel bolt. The string tension holds the neck in place and the bolt is really only there to prevent the neck being bent backwards when the strings are taken off. The toothpicks are to locate the heel block when gluing.

Heel block glued in place.

[Gogzs]

On 2/4/2022 at 4:05 PM, Dave Higham said:

Moved the sawn-off piece round the back, inserted the dowel pins and glued it back together. I realise that this makes it the equivalent of a one-piece, Gibson-type neck, but it’s easier than a scarf joint.

Was confused at first and surprised no-one thought of that before. But once you get it to thickness it'll be basically a scarf join, the kind of join I see less often around here:

So basically method 2 just with the comfort of having a loooot of extra material making it easier.  But again, clinical work, with the pins and everything, awesome.

[mattharris75]

8 hours ago, Gogzs said:

Was confused at first and surprised no-one thought of that before. But once you get it to thickness it'll be basically a scarf join, the kind of join I see less often around here:

So basically method 2 just with the comfort of having a loooot of extra material making it easier.  But again, clinical work, with the pins and everything, awesome.

 

That's how I do it too. Puts the joint in the middle of the headstock. The wings go on the headstock, the headplate and backstrap go on, it's an invisible and strong joint.

[Dave Higham]

I added two carbon fibre tubes to reinforce the heel.

Drilling the hole for the (barrel) bolt after having cut the tenon and drilled the hole for the barrel nut. The piece of dowel was a force-in fit which means no break-out when the drill goes through the barrel nut hole.

Here’s what it looks like with the hardware in place.

I now have to drill the holes for the two brass plugs that sit on the adjustment screws. I started by making this little jig. The holes are drilled on accurate centres in the milling machine and the slot is being cut to just slide onto the tenon.

Here’s the jig in place on the neck tenon.

and here are the holes being drilled. Of course, I forgot about the two CF tubes so they got drilled too. If I’d thought about it I’d have made the brass plugs shorter.

So here it is with the brass plugs in place.

[Dave Higham]

Got a bit distracted by other things, anyway, here's a bit more.

Milling the recess for the neck extension to support the cantilevered fingerboard.

The neck extension glued in place. I thought I’d make it out of something stiff and maple was the stiffest wood I’d got. Afterwards, I realised it would have looked better in mahogany as it will be partially seen.

I now had to route slots for the carbon fibre stiffening bars and the truss rod. I decided to add two short lengths of CF bars as extra stiffening for the neck extension. The blocks of MDF are improvised stops on the improvised router table.

I let the bars into the fingerboard. Here they are, being tried for size. Yes, people have told me I’ll never be able  to get the fingerboard off again, but I don’t ever intend to.

Now then, for those of you who haven’t yet been bored comatose by the length of this saga, are you still awake enough to have noticed the glaring mistake I made?

Yes, of course, the short pieces of CF should be on the OUTSIDE!!! After giving it the good old anglo-saxon four-letter-word treatment I went back to the drawing board and decided that I should just get away with it if I took care carving the neck. Good job Daniel didn’t want a V-profile. That would probably have meant starting again. So onward and upwards (hopefully) and trim the other ends of the long bars.

[Andyjr1515]

I remain in awe with this build.

Just a point that I might have missed in the posts - have you predetermined and built in the neck angle?

[Dave Higham]

On 2/23/2022 at 10:15 AM, Andyjr1515 said:

have you predetermined and built in the neck angle?

Perhaps I didn't explain earlier. The neck will be fully adjustable. The neck block has two threaded inserts with two pointed grub screws with the screws pointing towards the neck. The holes in the two brass plugs, which you can see a bit further up and which will be glued into the neck, sit on the points of the grub screws. This allows the neck to be adjusted 'sideways' so the centre line of the neck can be aligned with the centre of the bridge. The neck can also tilt backwards and forwards on the brass plugs to adjust the action and this is controlled by a screw through the heel going into a barrel nut, also located in the neck block.

What had to be predetermined was the positions of the above relative to the neck and body, so as to be able to adjust the neck to give more than enough string height without the end of the fingerboard hitting the body. Does any of that make sense? It gave me a headache!

[Andyjr1515]

2 hours ago, Dave Higham said:

Perhaps I didn't explain earlier.

Ah...yes you did!

2 hours ago, Dave Higham said:

Does any of that make sense?

And yes it does

Excellent 

 

 

[Dave Higham]

Before gluing the CF bars in, I needed to route the slot for the truss-rod. I didn’t get that wrong ‘cos it’s in the middle. Here it is with the rod being tried for size.

It’s an Allied rod and they recommend gluing a fillet on top of it, so I made the fillet and masked off the face of the neck blank to reduce the chance of getting glue where I didn’t want it.

Then I glued it in.

Once glued, I skimmed the fillet down flush with the surface of the neck. Having built mostly electric basses and frequented the bass forums I find it amazing the lengths to which some people will go, building complicated jigs to do everything with a router; especially scarf-jointed headstocks. I just love using a plane with a sharp blade.

I had to glue a couple of wings onto the headstock and they’re glued on like this to match the grain direction of the rest.

Then they got planed down flush to the headstock front.

 

[Dave Higham]

Mmm . . . got bogged down a bit by various things including a (very mild) dose of the plague, but I’ll try to make more progress.

 

Remember what the tail graft looked like? I decided to make a headstock ‘decoration’ to match. Oh, and this is why the tail graft got installed ‘upside-down’. I didn’t do it intentionally, I just got used to seeing them like this and installed the tail graft without thinking about it and although you can’t really see them both at the same time, in this case it does seem like the ‘right’ way up to me.

Here I’m routing a recess for my pearl logo with the home-made pantograph. It actually works surprisingly well

So then I glued the headstock veneer on, cut off some of the surplus and it looked like this.

Off-cuts from the back to make a bookmatched backstrap veneer. It looks as if I used fish glue.

I cut most of the surplus off on the bandsaw and then sanded  the back of the headstock to thickness.

These are the bits that are going to be glued onto it.

 Bending the maple veneer on a hot pipe is easy. Bending a bookmatched veneer 2mm thick isn’t. Of course it came apart, I’d used fish glue hadn’t I, and how do you get things apart that have been glued with fish glue?  But I managed to glue it together again and it doesn’t show much. And here it’s getting glued in place.

Voilà! (Yes, it’s voilà, not viola; that’s a sort of oversized fiddle).

[Bizman62]

Seeing the simple glueing board with wedges made me happy! I knew about it but it's a rare sight - most often you see some sort of "innovative clamping". "Nothing that simple will work..." And another nice use of a wedge to secure the vacuum along your sander.

Another pleasure was to see "voilà" spelled right, even the grave accent is the right one.

Such tiny things made my day!

[Dave Higham]

5 hours ago, Bizman62 said:

Such tiny things made my day!

My pleasure!

[Dave Higham]

Now I can cut most of the surplus off the headstock. It looks a bit hairy doing it this way but it works OK if you’re careful.

There! It looks like a headstock. You’ve noticed that part of the ‘decoration’ is missing. Well, how else was I going to get at the truss rod? I decided to make a flush fitting cover that wouldn’t be seen as such, so part of the ‘decoration’ wasn’t glued to the rest.

Now I can route the headstock’s finished shape with the help of a template and locating pins

It’s going to be a bound headstock so I need to route a ledge for the binding and purfling. I always have problems with this as, when you get to the corners, there’s less than a quarter of the router base in contact with the headstock surface and the slightest wobble cuts a divot in the ledge.

So after I’d finished I made another base for the Dremel. That way, I won’t be tempted to try it again with the Stewmac base next time.

Now I have a nice clean ledge for the binding and purfling.

[mistermikev]

maquaray (spelling?) work is something else.  really classy touch, bravo.

[Dave Higham]

7 hours ago, mistermikev said:

maquaray (spelling?)

Stumped me for a minute. Did you mean marquetry?

[mistermikev]

2 hours ago, Dave Higham said:

Stumped me for a minute. Did you mean marquetry?

yeah, worlds worst speller here... but yeah!

[Dave Higham]

The binding isn’t going to bend to fit the three tight radii without some help, so this is what I do. (I may have shown this before. As these are regurgitated threads, I’m not quite sure. Anyway, I make a couple of male and female forms from MDF. Then I drop a piece of binding in boiling water for a couple of minutes, fish it out, and clamp it between the two forms. Then I put the whole lot into the oven on the lowest setting for about ten minutes and when it comes out and cools down it keeps the shape perfectly.

The two long pieces bend easily enough, but with the help of another form I glue the purfling to them and they almost keep their intended shape too.

The one on the left is one of the pieces for the curve where the headstock meets the neck. The one on the right is for the end of the headstock. This is the second one I made because on the first one I glued the purfling on the convex side like all the others! (eyeroll). As someone said “I’ve learned a lot from my mistakes, and I’ll probably learn some more”.

Here are all the bits glued together. I didn’t take any photos of myself gluing my fingers to it. Been there, done that. Have you noticed a difference in the truss rod cover?

Here are all the bits glued together. I didn’t take any photos of myself gluing my fingers to it. Been there, done that. Have you noticed a difference in the truss rod cover?

So I had to thicken the cover with a piece of maple with a hole in it which allowed me to glue a magnet solidly to it, and bevelled the edges so that, although it’s not as discrete as I wanted, it still blends in. I then, of course had to glue another magnet into the headstock like so.

If you look carefully, you’ll see that the cover is lined up with its recess, but that the magnet in the cover is slightly nearer the nut than the one in the headstock. This means that the magnet in the headstock pulls the cover up into its recess. I wasn’t sure it would really work, but it does. At this point I hoped someone was going to say ‘But how will you get it out?’ but if you’ve seen it before, you’ll know.

[Bizman62]

39 minutes ago, Dave Higham said:

the magnet in the headstock pulls the cover up into its recess. I wasn’t sure it would really work, but it does.

Clever! I would never have thought about that although it's common knowledge that the magnets want to align if their polarities are right.

[Dave Higham]

Oh well, never mind. Can you see that little slope I’ve chiselled into the cover recess?

Well, that lets me get it out. Like this. Of course I’ll probably have to loosen the D and G strings, but I never said it was perfect!

Now for the fretboard. I don’t have a template for the fret spacing so I just measured and marked using the Stewmac calculator

I made the fret slotting jig for two fanned fret basses I made, but it obviously works just as well for parallel frets. After all the slots were cut I ran a triangular section needle file along them a couple of times to create a slight chamfer. It helps the frets go in and reduces the chances of chipping if they ever have to come out again.

Sanding the radius on the fretboard.

Action shot.