Dave Higham

I decided to have a go at an arm-rest bevel which meant I needed a much thicker lining in that area. I had a lot of helpful advice from Texan luthier Steve Kinnaird on how to do this so I followed his method. There are 7 laminations, each about 2.5mm thick, so I had to bend them roughly to shape on a hot pipe before gluing them together in situ. They are not yet, however, glued to the side. Here, 5 are glued and 2 to go. All glued If I’d thought about it a bit more, I’d have made this before gluing the tail block in place. As it was, I had to fit one end of the first 3 strips to the tail block (the 45° angle). Smoothed out the steps inside. Did a bit of spoke-shaving and sanding. . . .and finished up with this. Trimmed it to length, glued it in place, fitted and glued the other linings and this is the result. And a view from the top. I glued in some side strips. These are supposed to stop the sides from cracking if they receive a shock or, at least, prevent the crack from travelling. Some just use calico strips glued to the sides. Some think they are a waste of time and don’t bother. In case you’re wondering how that hole in the side got there, it got there with the aid of a drill, a jigsaw and some files and sandpaper and it never crossed my mind to take any photos of the process. In this photo it still needed a bit of work; elliptical holes on a curved surface aren’t as easy as I thought.

Gluing the first strut and its buttress in place. The CF tube is glued into the neck block and the buttress with epoxy and the buttress glued to the side at the same time with fish glue. The same strut seen from the other side. Both struts and buttresses glued in place. The linings are then notched for the buttresses and glued in place. After a little more work with the radius dish, this is what it looks like. You can see from these photos the peculiar shape of the linings. The front linings were much easier as they started out straight. I also made an improvement to the form by screwing on these guide pieces. It made it much easier to use.

Thank you Andy.

Many people think that the more rigid the sides are the better, and solid linings stiffen the sides up quite a lot. Some laminate the sides which makes them even stiffer. Some even laminate them with a kerfed core, which makes the sides so thick that thay don’t need linings. That’s a bit beyond my scope so I decided to make laminated spruce linings The outer form of the jig is hinged in two places. It makes it slightly easier to get it together when the laminations are trying to slide all over the place. Mine were especially trying as I decided to profile them like the sides which also meant that they had to go in the form at an angle. This also meant that, as the back linings are profiled there is a right-hand and a left-hand lining and, because of the wedge body, they’re not reversible. The first lining I glued up didn’t seem to fit the side or follow the profile at all. Then I realised I’d made it ‘wrong-handed’ so I had to make another one. So when I made the lining for the other side I thought long and hard about which way round it had to go in the form and then made that one ‘wrong-handed’ too! (Told you there were cock-ups). But before gluing in the linings I have to make the buttresses for the Carbon fibre struts. Two bits of wood and two wedges to help me drill the holes at the correct angles. One of the holes being drilled. Then they are sanded to fit the sides in the same way as I did for the tail block. More sanding And shaping the profile.

After the sides were trimmed, the neck block was glued in place. This needed a few clamping cauls because of the complicated shape. Here it is glued. And the tail block getting glued. Then a session of ‘driving the bus’ to sand the sides and end blocks to a 15 foot radius using the sanding dish at 2.34 p.m.. It doesn’t take long, thanks to the pre-profiled sides; even so, power steering would be nice! This is the result. Although I didn’t think to take a photo, I chalk all the surfaces to be sanded, so when there’s no chalk left, I’ve sanded enough.

I’d decided to attempt a Florentine (pointy) cutaway so I started by making a simple bending former. Here it is in action. It’s in the cooling down stage here. I don’t muck about trying to take photos while it’s heating up. Bending the rest of the treble side on the home-made Fox-type bender. The rest of the side bending went more or less OK. There was some spring-back but the sides went into the mould fairly easily. I started assembling the sides by gluing this block into the pointy cutaway junction. I actually managed to get a good mitred joint of the two side pieces, but I can’t remember for the life of me how I did it L. Which is a pity, because I want to do another one. Then I trimmed the sides so the rest of it fitted into the mould.

Thanks for your comments @Andyjr1515 and @Gogzs. I spent my working life in engineering so I suppose it shows.

True. It also makes very nice acoustic instruments.

Wenge, oak, padouk, ebony and maple! ! ! How much does it weigh?

I started on the sides by drawing profiles. Profiling the sides before bending means there’s a lot less to carve off to fit the back and front. It also means the off-cuts can be used for bindings. The mould is placed on the radius radius dish with spacers of different thicknesses to allow for the difference in depth of the body at neck block and tail block, I also had to use different spacers at each side because of the 20mm difference in the wedge. A piece of thick paper or thin card is taped to the mould and a line is then traced using a piece of pencil lead stuck into a small wooden block. This is done for both sides because of the wedge. The resultant profiles looked like this. Linings are obviously going to be fun, not to mention the bindings, but I might even be able to get profiled bindings out of the off-cuts.

I need to sand a curve into one side for the cutaway. So that’s the neck block finished.

Milling holes for carbon fibre struts. Why carbon fibre struts? Traditionally, steel strung acoustic guitars have a neck block to which the sides, back and front are glued (not necessarily in that order). The neck was most commonly attached to the block by a glued dovetail joint. Under the constant tension of the strings this assembly can deform. The area of the soundboard between the neck block and the soundhole can become slightly concave and the neck leans forwards, the neck block effectively rotating forwards. The carbon fibre tubular struts are fitted between the front of the neck block and the sides near the waist to prevent this happening. The first person I came across doing this was Rick Turner, co-founder of Alembic. The struts were let into the neck block at different compound angles because it’s going to be a wedge shaped body; deeper on the treble side than the bass. These are the little jigs used to form the compound angles. I think now that I could have made them both at the same angle and it would probably have worked just as well, but, as the French say,”why make it simple when you can make it complicated?” One of the two retaining bolts will also be used to adjust the neck angle (through the heel from the outside) and the little maple block will house the barrel nut on the inside. The mahogany block is reinforcement. It sounds complicated (and it is a bit) but all should become clear. Here they are all shaped and glued together. By the way, I didn’t invent anything here. Stauffer (to whom C.F.Martin was apprenticed) made guitars with adjustable necks in the 1840’s. In fact, all the features I’ve included on this guitar have already been done by someone else in one form or another. Rick Turner said “there’s nothing new in luthery”. As soon as you think of a ‘new’ idea, you discover that it’s already been done. Ralph Novak managed to patent the ‘Fanned Fret’ idea but shouldn’t really have been allowed to. Multi-scale fretted instruments have been around since the 1600’s.

How about an etched metal pick guard. Copper perhaps?

Machining the block for the neck tenon, etc. The other piece of mahogany glued on to form a sort of Spanish foot. The foot is hollowed out. It’s not to make it lighter but to reduce the area to be sanded to fit it to the concave surface of the back.

To make the tail block as good a fit as possible when gluing to the sides, I stick some abrasive cloth to the mould with double sided tape and, with a couple of guides clamped in place, rub the block on the abrasive. A few pencil or chalk lines on the block show when I have contact all over. I’ll leave the tail block there and start on the neck block. This is a bit complicated because of the adjustable bolt-on neck. It starts with a bit more plywood, a bit more mahogany and a bit of maple. Mahogany cut and trimmed into two pieces and the plywood glued to one of them and trimmed to size. The two central holes are for the bolts and the two larger ones are for threaded inserts. Threaded inserts being installed.

I do have the Stewmac set-up and you're right, it's expensive but I've found it good for delicate stuff like rosette rings. A solution for cutting through is to use a backing board. The pin goes through the workpiece and into the backing board.

Made one! Not tried it out yet, but will soon.

It's the tail block, and the hole's for an access panel. Lets me get inside to adjust the neck (if necessary) without taking the strings off.

This is another piece of birch ply being sanded (on a slightly simpler jig) to fit nicely into the hole in the tail block. This will be the access panel. I realised, much later, that it doesn’t need to be a good fit and is even better with space between it and the tail block. But that was much later. Here, the mahogany side of the tail block is being sanded to the profile of the lower bout. The plywood disc is taped into position just to fill the hole because, without it, the sanding dust shot out through the hole and straight into my face. . So here’s what it looked like at this point.

It well might. I'll look into it.

Mmm. . . I'll have to think about that. The big router's too big. The Dremel would bounce off 1/2" birch ply. The palm router might work but adjusting the diameter would be the problem . . .

Not sure what you mean by the 'router on a stick' trick, but I'd like to know. When I did this I was thinking the hole needed to be a precise diameter and perfectly circular (not quite the same thing) and this is the method I came up with using the means at hand. I later realised that it didn't need to be so perfect but that's often how one learns - from experience. I'm actually getting ready to do this again so, as I said, if there's a better way I'd like to know.

About 10 years ago my nephew Dan asked if I’d make him an acoustic guitar. He knew what he wanted; an OM with a cutaway. I was frankly less than enthusiastic. Why? Well, I made electric bass guitars, I made them for fun and I made them for me. That way, if the customer wasn’t satisfied… I really didn’t want to make something to order, so to speak, that either he or I might be disappointed with. After all, the dreadnaught I made in 1971 was not really a success. It looked OK but it sounded crap … and it didn’t have a cutaway. I had made an acoustic bass guitar which looked nice… but that didn’t have a cutaway either. And anyway I had started making my next bass. But after I’d made that bass, a year or so later, I didn’t really have room for any more. And anyway, I fancied a change so I decided to have a go. But I also decided not to tell Dan, so if it turned out to be a clunker he wouldn’t know, so he wouldn’t be disappointed. So this is how it went. It’s quite a long story. I decided I’d try to include almost all the bells and whistles I could think of. So it would have a cut-away, a wedge shaped body for comfort, shallower on the bass side than the treble, an adjustable bolt-on neck, an access panel to be able to get at the adjustments without taking the strings off, and an arm bevel, also for comfort. Claro walnut back and sides.Lutz spruce top.Honduras mahogany neck.Ebony fingerboard. Starting with the tail block which consists of a bit of mahogany (off-cut from a bass) and a bit of old-growth birch plywood (I call it ‘old-growth’ because it’s very nice all-birch ply that I retrieved when we took it out of a shop we refit for my old boss about 40 years ago). Glued them together, stuck a print of the drawing to them and trimmed them to size. (I draw up plans in 2D CAD for the instruments I make before I start. They also seem to get modified quite a lot along the way). I roughly cut out a hole in the tail block with a jigsaw, but it really needs to be as smooth and circular as I can get it. So this stack of bits consists of1. The tail block 1. The tail block 2. A spacer with a larger hole in it 3. A carrier with a 5mm hole in the middle 4. A base with a 5mm hole in the middle. The tail block is dowelled to the spacer and the carrier, and the carrier rotates on a dowel through its central hole and the base. The base is clamped to the drill table and the hole sanded by turning the tail block. Sanding increments are increased by delicately hitting the base with a hammer . By the way, this isn’t a ‘How to do it’ thread. This is ‘How I did it’ and, as you’ll discover, it’s sometimes ‘How I made a cock-up of it’, so if anyone has any suggestions for ‘How I should have done it’, please feel free!

I realise that most of the interest here is in electric instruments but I seem to remember seeing the odd acoustic in the dim and distant past. There's Ash's rabbit hole, but he seems to have disappeared down it The acoustic in question was made for my nephew and finished in 2017, so it's not a new project. It would be quite a long thread with a lot of photos. So what do you think? (I could do an electric afterwards).

I only have a Panasonic Lumix about 12 years old and only found that feature after I'd had it for a few years. You know what they say, RTFM! I use it for every photo, especially in the workshop where I have 'warm white' bulbs in Anglepoise-type lamps, fluorescents overhead and daylight coming through the window. You don't need a white wall, you get the camera set up on the subject, then set the colour correction by putting a sheet of white paper in front of the lens. I also use Photoshop elements to correct framing, brightness and contrast. That's all I did to convert the first photo into the second one.