Another hand-tool LP from scratch!

Discussion in 'Luthier's Corner' started by Barnaby, Dec 18, 2011.

  1. Barnaby

    Barnaby Premium Member

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    Right then!

    This is my second build thread for a carvetop guitar using only hand tools. My hope is to construct an instrument efficiently using various things I managed to learn over the last few guitars. Some of these are things I figured out myself, but many more are techniques and bits of knowledge imparted to me by very kind and patient forum members.

    I’ll try to keep the thread relatively concise this time in order to provide a useful reference for anyone who wants to try a hand tool approach for part or all of their own build. There are lots of ways to manage specific tasks, and I may mention some alternatives along the way.

    I have a few non-standard tools that I will be using. Some things that I use as alternatives to common power tools are:

    Bandsaw – Bowsaw
    Electric drill – Eggbeater drill
    Drill press – Bit and brace
    Electric router – Router plane
    Thickness planer – Hand plane

    Personally, I find these tools convenient, quiet, clean and efficient to use. They’re also generally much cheaper and safer than the powered equivalents, especially if you do a bit of hunting around for secondhand ones and don’t mind a bit of restoration work. I also make extensive use of chisels, gouges and a couple of other specialist tools, like a small, convex detail plane.

    Here are some of the tools in question. In the first photo is a #4 smoothing plane, a low-angle block plane, a small convex detail plane, a Shinto saw rasp and a couple of nomi (Japanese chisels).

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    In this photo, there’s a brace and some bits, a router plane, an eggbeater drill and a ryoba (Japanese double-edged saw).

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    Two other things I have learned along the way and mentioned on other threads are sharpening and tool practice. First off, a sharp tool is a safe tool, as you’re not applying too much pressure. It simply does its job well. I sharpen my plane blades, chisels and gouges regularly, using waterstones and finishing with a compound-charged strop. This has the double benefit of keeping the tools nice to use and giving me lots of practice at sharpening. The more I do it, the better the edges I create are, and the better my tools work.

    As for tool practice, the premise is simple – I try to understand a tool properly before attacking an expensive piece of wood with it. Therefore, either practicing on scrap or doing small woodworking projects (like boxmaking) is an essential part of this process for me. This is because I am a completely self-trained and largely talentless woodworker. I need all of the practice I can get to even cut a straight line, let alone make an actual instrument that works.

    On to the instrument itself. The specs are pretty straightforward, and any steps I include which are a bit unusual or undesired by anyone else following my build (like chambering) can simply be skipped. The guitar will have a Honduran neck and body with a solid maple cap. The fingerboard will be Macassar ebony and the headplate and backplates will be African ebony. The binding will be cream and the inlays will be paua abalone. I will wind my own pickups. The body will be chambered fairly extensively, and there will be one mild surprise in headstock construction, which I will explain when the time cones. The dimensions will be as close as I can manage to a ’59 with the exception of the headstock.

    The finish spraying is the only part of the build using power. I will use an HVLP spray setup because it is quiet and more environmentally friendly than others, creating less overspray. Before, I bought spraycans of lacquer, which was both wasteful and expensive. Also, this meant that I couldn’t spray a burst, which I hope to on this instrument. It is possible to stain a burst by hand and apply a brushed lacquer finish or oil, but I really want to try the spray method this time.

    One final note – I was planning to put this thread up all at once after reaching the endpoint, but there are a number of hand tool builders trying some different things now, so I thought it would be timely to put up my progress so far to help them out. An early Christmas present?
     
  2. Barnaby

    Barnaby Premium Member

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    On to the build itself. The first part is the body. This is a nice, solid piece of Honduran. I am going to chamber it fairly extensively, as mentioned, but anyone wanting to do a ‘vintage’ build can simply skip that bit.

    I start by marking up my blank which I have planed flat to 45 mm (2mm will come off in subsequent finishing steps). From here, I work out the body shape and attach my two MDF templates. These are held in place by bolts through the body at the switch and control cavities, so the holes will vanish once the body is shaped. I use an eggbeater drill and go halfway from each side, as the drill tends to wander, even in this stand.

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    From here, the template is attached on both sides and the body shape is cut out using a bowsaw. This is pretty accurate and takes less than an hour for the whole thing.

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    The edges of the body are cleaned up using a block plane first of all. I work from each edge inwards, but never across to the opposite edge, otherwise there is a risk of tearout.

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    The extra material in the waist and cutaway is removed first with a small, convex plane with a handle. This takes up chips of wood very quickly and cleanly. Then, the curve is smoothed with a curved file. I also use the Shinto rasp (a saw rasp) to smooth everything further.

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    The whole process of getting a basic blank ready takes a bit more than an hour and a half, including bowsawing and cleaning up the sides.

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    After this, the chambers are marked on. I won’t cut them just yet because of the risk of warping. Humidity is high right now in Tokyo. I’ll do them once the top is carved and ready. They’re pretty extensive, as you can see from the photo below. I have added a centre spine between the tailpiece block and the endpin to this body, as I want support for the top join and also suspect that it might be a little ‘boomy’ otherwise. I’m just guessing, of course. We’ll see how it turns out.

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  3. Barnaby

    Barnaby Premium Member

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    Time for choosing some wood for the top. I have two pieces of maple and I lay them out to have a look.

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    After some thought and a chat to my wife, I decide to go with the one on the left. It is more highly figured, which is appropriate for this guitar, as it’s not an LP replica. Personally, I prefer less figured tops on replicas, and will maybe save the other piece for that. Here’s the one on the left in more detail.

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    Nice, even flame. I’m hoping it will be pleasant to work with.

    Jointing the halves is relatively straightforward, but there is still room for all sorts of messing up. I start by sharpening the blade of my jointer plane until it is as good an edge as I can manage. Here it is next to the halves clamped in my bench. The plane is nearly as long as the wood, which is a good thing, I think.

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    I set the blade to take an extremely fine cut and start bringing up wispy shavings.

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    Without changing the blade depth, I continue until I have even shavings across both boards. I check the angle of my surface relative to the sides regularly with a small set square and use pencil marks to assure myself that the surface is flat. I also check with a straight edge.

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    From here, I spread Titebond on both edges and join using sash clamps. Because the maple has an angled upper half, I have made a couple of small blocks from pine so that the clamp jaws sit flat and don’t apply uneven, twisting pressure. I put a piece of cling wrap under the wood when I rest it on the bench, as I don’t want it to glue itself to the top!

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    Now, I wait for 24 hours…

    …and, through the miracle of the Internet, suddenly have a glued up piece of maple. I attach it to the workbench and plane it flat on both sides. I find the jointer is best for this and it takes some time to find the ideal blade depth and approach angle for each side in order to minimize tearout. Still, I get there in the end and have an invisible joint. I mark where my top will be and, using the bowsaw, cut out the shape in one long, careful cut. There’s a reason why I’m doing this rather than many little cuts...and it will (I hope) make sense when you see how I carve the top.

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    This is the result. The flame isn’t too bad, I think.

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  4. Barnaby

    Barnaby Premium Member

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    I have several pieces of Macassar ebony, one regular West African piece and an Indian rosewood blank as possibles for this build. First of all, I take them all out and have a good look. None are ugly enough that looks disqualify them from this build, which is enough for me. From there, I take some time to hold each one between thumb and forefinger and tap with my knuckles, listening to the tones. All of the Macassar pieces are pretty resonant – almost a Dalbergia Nigra sound – and the West African is also quite nice, but the rosewood lacks depth. After a bunch of tapping, one stands out in terms of the sound that I want for this build. Here it is. A nice piece, with a relatively straight grain.

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    I don’t really know what I’m doing when I tap the wood. I don’t know what I’m listening for exactly…although there is something there for sure. My idea is simply to keep at it as I build and, hopefully, some sort of knowledge about the relationship between wood choice and tonal characteristics will come out of it.

    In any case, the blank is first planed to thickness – just a hair over 6mm for this build – using the #6 and #4 planes. This wood is very sensitive to direction – a smooth cut one way turns into horrible tearout the other, so I need to plane carefully. Still, it gives lovely, chocolate-ish shavings.

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    Next, the size of the board itself is marked. I am working to 56mm at the wide end and 41 mm at the narrow, over a 457mm length. I mark my centrelines with pencil, but the ‘waste’ gets marked with a white wax pencil so that it is easy to see. Once the basic shape is cut out, I simply plane it to the correct dimensions. I use the #6 for the long sides and the low-angle block plane for the ends. Everything is straight and at 90 degrees. The tap tone is nice as well – a deep, rich ‘bonnnnnng’ sound

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    Here is one side of the board with the main inlay – a shark – sitting on it.

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    One change that I made to my methods was to buy a mitre box and Japanese saw to fit. If only making a guitar or two, this is not necessary but, for a lot of fingerboards, it saves time and frustration and gives a great result. I mark to a 624.5 mm scale length.

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    The main inlay is cut in using small chisels, knives and a scribe to start with. I put on an optic visor to get a good view – it makes a very large difference – and work away. The remaining inlays will be offset 4mm paua dots.

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    The board is trimmed by being put in a clamp and planed down to the correct dimension first with a block plane to clean up the angle and then a #6 jointer to make sure that the sides are straight and at 90 degrees.

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  5. Barnaby

    Barnaby Premium Member

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    Back to the body of this instrument. It’s time to put some holes in it. I start out with the brace and some bits. When drilling with a larger forstner bit through thick wood, I find it best to set the piece on the ground so that my body weight gives the power needed. The brace is very easy to use and surprisingly accurate. I start by drilling out the hole for the switch. Note the ‘sacrifice’ wood under my mahogany to minimize tearout. It’s also a good idea to bore a little from the opposite side first for this reason.

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    If I were doing a ‘vintage’ build, I could stop this before reaching the top of the body, leaving some mahogany in there. I have no such constraints this time, however, so it’s straight through.

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    Last build, that took ages and was nowhere near as clean. Now, it looks nice and took only a minute or so.

    Following this, the four holes at the corners of the control cavity are bored using the same techniques.

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    A bowsaw removes the rest of the material quickly, after which it is filed and sanded. Once more, I could use the forstner bits and the router plane if I wanted to leave some mahogany in the top of the cavity, but I won’t worry this time.

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    Next, the switch cavity is marked, knifed and cleaned out to the correct depth with the router plane. Again, this is a very quick process compared to the way I did it last time.

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  6. Barnaby

    Barnaby Premium Member

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    The neck is cut from the same blank as my previous build…so it feels like I’m getting the wood for free!

    Last time, I used a coping saw and a Japanese Ryoba (or double-edged saw) to do this job. It took all day and was a killer. This time, I simply put a 10tpi blade in the bowsaw, lined it up using a mirror to make sure I didn’t stray too far away from my line - and went to work.

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    Another thing that made the job much, much faster was using a decent workbench. Last time, I was doing everything on a dodgy folding trestle thingy. This time, I could clamp the wood firmly and saw without having to worry about everything moving around. Once the blank was cut out – which took less than an hour this time – I simply cleaned up the main surfaces with a block plane and used the detail plane with a curved base for the rounded parts.

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    Here’s the blank before it gets cut into final shape.

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    If you have never planed mahogany before, then go and get a bench or block plane, sharpen the blade, put some mahogany in your clamps and start right now. It is fast, easy and deeply satisfying on a visceral level. Go now. Run!

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  7. Barnaby

    Barnaby Premium Member

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    The next step was to work out my top contours. I decided I would make some ‘stepped’ contours, as many others have, in order to guide the carve early on, based on the information to hand. I have included a brief description of how I arrived at my top contours so that anyone who wants to can do the same process – or modify mine and make it better. I measured and worked things out largely by eye and with ordinary rulers. Probably not the most accurate, but it should get me close enough. My reference materials were the Bartlett, StewMac and Catto plans, a copy of BOTB and a couple of genuine 1959 bursts that I couldn’t physically measure but I could eyeball and see roughly if I was close enough.

    I know that Tom Bartlett has already done an excellent carve model, but I have no wish to simply copy his research and call it my own. If I want an Eastern Maple Carved Top, I’ll buy one (and I may well in the future, as they’re beautiful things)! I find it more valuable to come up with my own dimensions for this build, however. I’m not sure how close it is to the Bartlett top, but I hope it is within spec for a ’59. After all, as we all know, they were finished by hand and there was considerable variation.

    First, I drew four lines across the body at the points where I thought they would be most useful for getting an idea of the curve, following roughly where the StewMac plans did the same thing (but winding up with some different measurements). These turned out to be at centreline points A (71mm), B (147mm), C (235mm) and D (292mm). I also added a line from the end to the intersection with D, called line E (140mm). Then, I measured the width. According to the Bartlett plan, the upper right bout is actually not quite symmetrical, but I figure that’ll be a minor issue in carving. That also matches with the originals I saw – it’s subtle, but there. This, combined with the heights I worked out based on pickup and neck plane angles and assuming a highest point of 15.0 mm (John Catto gives between 9/16” and 5/8”, or 14.3mm and 15.8, so I chose something conveniently in the middle) as the thickness, gave me a cross-section ‘box’ for each.

    From here, I spent some time simply measuring a bunch of BOTB pictures and trying to figure out what the reflections told me about how the carve worked. I measured a lot, but, just for the curious, the one I worked with the most was 9-1864. I divided each box into three sections – the shallow, almost flat top carve, the steep curve on the side and the slightly dished recurve at the bottom. I also went and looked very hard at some originals with my notes in hand and tried my best to see if they matched. I made a couple of revisions after that and wound up, at last, with five cross-section profiles.

    Once these were done, it was a relatively straightforward matter to work out the rest. I simply worked out on each cross-section where the 2mm ‘steps’ were, marked those on a blank body outline and connected them with curves. These became my contours. The way they work is basic enough – the innermost contour is the top, and each one after that is the next 2mm step down. There are five in total. The recurve is not marked, as I think it should be done by hand, and I am assuming that the pickup and neck planes will be cut after the main curves have been put into place. Personally, I will cut in the steps 1mm above ‘true’ height to allow some leeway when carving/sanding down.

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    My points on which the curves are based are below, and free for anyone who wishes to use them. They are based on my own research, observations and assumptions, unless otherwise noted. I have tried to derive my measurements from scratch rather than relying on existing plans and used several different body plans as my references. If enough people want a PDF, I can probably do one based on the stuff I have, but it’s not hard to draw your own plans based on the figures below. Also, if you draw your own, the curves will be slightly different from mine, which will mean you’ll have something all your own to work from.

    Curve points - reading from the left. Numbers in brackets are the length of the total line from the edge to the centreline):

    Line A (118mm): 32, 48, 51, 65, 98
    Line B: (93mm): 25, 31, 38, 44, 65
    Line C (148mm): 32, 52, 64, 75, 90
    Line D (165mm): 36, 55, 68, 84, 100
    Line E (140mm): 38, 57, 70, 86, 107

    This is probably confusing to read, but I hope it will be clear(ish) if you look at the photo and spend a couple of minutes with a pencil and paper trying to map my contours. Draw a line (the centreline) down a large piece of paper – A3 is good – then trace half of the LP body shape onto it. From the top point of the intersection between the body outline and the centreline, mark points A, B, C and D. Draw lines out to the edge of the body outline at right angles to the centreline. These should be roughly the same lengths as in the chart above. Then, mark off the points given. Don’t forget line E, which is actually the last 140mm of your centreline. Connect the dots with sexy curves…and you have yourself some contours.

    With contour lines drawn, I mark the first on the top itself and use the router plane to clear my first ‘ledge’. The top is screwed to a piece of MDF which is, itself, screwed to the workbench surface.

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    In the first photo, note the surround…remember I said that the way I cut the top out would make sense? Well, the offcut maple acts as a ledge for the router plane. The second ledge is provided by the uncut centre of the top itself…a sort of ‘island’.

    In the second photo, note that the router plane is bolted to a piece of wood to give it extra width. I put a hole in the middle for the blade and simply plane away.

    One positive of this process is that it is much faster than the drill method. The first ledge takes a while – it is wide and must be 6.5mm deep, but successive ledges, as the top is 20.5mm and I want it 1mm above ‘final’ height, or 14mm high – but subsequent ledges will be much, much faster to do, being both thinner and progressively narrower. Next, it is quiet, which is a major plus for me. Finally, instead of sawdust, I get beautiful maple shavings, which will go to my friend Mike for his barbeque.

    Another point to mention is that the wood has a definite opinion about how it wants to be worked. The right side requires planing towards the upper bout, but the left must be planed towards the lower. To do otherwise invites tearout.

    This is about three-quarters of the way through the whole thing.

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    Finally, with the ledges routed, the side frame is removed and the topmost section is planed to thickness.

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    Here is the top after all of that work – about six hours total to get to this point, I think. My hands hurt, but not as much as they did the last time I was at this point of the top carve.

    [​IMG]
     
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  8. Barnaby

    Barnaby Premium Member

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    The next part of the body work begins with a jig.

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    Um…

    …anyway, I begin by planning two pieces of MDF until I have an angled wedge that I can use to guide my router plane. The angle corresponds to that on the base of the pickup cavities.

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    I cut a window in it for my work and add a drilling template. I measured the radius at the corners of the cavities at around 10mm, so that is what I went for here. Basically, I drilled (very carefully) a hole through the MDF at 90 degrees to the angled surface. Then, I added a bolt-on guide with a hole drilled straight through a large chunk of leftover mahogany. After this, I realized that, had I done these two tasks the other way around, it would have taken about half the time.

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    Anyway, the completed jig should allow me to use the router plane at the correct angle relative to a flat surface (it is a long enough wedge to give clearance) and also to bore holes in the corners in order to start the cavities off neatly. Let’s see how it works…

    Here are the cavity dimensions marked.

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    The angled holes drilled by hand with the jig.

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    Using the router plane.

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    The cavities done for now.

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    One point to note is that, the faster you descend, the rougher the cavity walls. Therefore, slower steps with the router plane will give a cleaner cavity, but take more time. This will all be sanded back (and maybe filled too), but I would have preferred a cleaner look straight off the bat. The second one looked better than the first, however.
     
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  9. Barnaby

    Barnaby Premium Member

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    The next part of the body is the making of the cavities. This would be skipped by the vintage buffs, but I want a lighter, more resonant guitar this time, so why not?

    I could take out the cavities with the router plane, but don’t need such a clean cut – and also am worried that the sole of the plane moving over the rest of the body could create little pits and dents. Therefore, I simply grab a gouge and go.

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    …and sanded…

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    Bar a bit more sanding, that’s basically it for the body now. It’s nice and light. Of course, I will continue to sand out the cavities so that there is only clean wood inside and sand the surfaces back for a clean join. I don’t want any possible buzzing or other issues down the track. That aside, however, now the body can sit until the top is ready to be attached.
     
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  10. Barnaby

    Barnaby Premium Member

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    To get the top to the point where it can be joined, I have three basic tasks to do. First, I have to rough out the carve. After that, I have to put in the pickup cavities. Finally, I have to do some undercutting in the control cavity and also to match the weight relief cavities in the body. I want to eliminate sharp edges in these cavities as much as I can.

    The carve is fun to do. The first part is putting in the pickup planes. This is very easy to do with hand tools. None of those hinged boxes or router jigs are needed. All I have to do is cut down until I have a flat plane that is 5mm at the neck edge and angled at 4.4 degrees. Then, I do the pickup plane in a similar way and I’m set. It just needs sharp tools and a protractor and takes about ten minutes.

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    Frome here, I simply smooth out the ledges using the small curved plane. It’s extremely efficient at this sort of task.

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    Follow it up with a cabinet scraper.

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    Then, I have a rough carve.

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    It’s mostly sanding and a bit of scraping from here for the top. Now I can put the pickup holes in without worrying that I’m going to take big chunks out of the edges as I do the top contours.
     
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  11. Barnaby

    Barnaby Premium Member

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    The next job on the headstock was to clean up the angle to exactly 17 degrees and mark on the headstock shape. With this done, I worked out the positioning of the tuner holes, bushings and screws and then decided how much of the material in the headstock could be removed.

    The idea behind chambering the headstock is that it is at the end of a vibrating rod (the neck) and must contribute to tone. Creating a hollow here should have some sort of effect, although I don’t know exactly what it will be. It will also lighten the headstock slightly and change the overall balance, although not by a huge amount, of course. I’m combining this with light, vintage-style tuners to maximise any possible tonal difference. I know that some people add mass to the headstock to increase sustain. I suspect that creating a resonating chamber will do so as well, but in a different way.

    The cavity is put in with forstner bits and the router plane to a depth of 7mm. It will have a 2mm mahogany cap, which I cut and do a preliminary fit for next.

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    This will be invisible once the binding is on and a fairly thin headplate of ebonized maple is added.

    From here, the truss rod cavity is cut using the router plane. This time, I run the slot down the whole length of the blank. The router plane throws up these really cool little curls of wood which I love making.

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    The end of the slot will be filled in with maple. As per Freddy G’s advice, I cut the slot slightly narrow and will leave it for at least 24 hours before sanding out the final 0.5 mm or so needed to fit the truss rod.
     
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  12. Barnaby

    Barnaby Premium Member

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    On to some electronics – I wind my own pickups, as I really think that it’s important to make as much of the instrument as one can. I use a hand winder that I picked up in Akihabara with my fingers providing tension and a bent bit of coathanger as a wire guide. The spacing on the guide is provided by two washers glued to rubber offcuts.

    These pickups are non-vintage, so I use poly-coated AWG42 wire. This also winds more easily and breaks less than the enamel stuff in my experience so far (which is, admittedly, pretty limited). I wind the neck pickup to roughly 7.8K, with one bobbin at 3.8 and the other at 4.0. A slight imbalance is probably good for tone. The bridge pickup is a bit hotter – 9.6K, with a 4.5 and a 5.1 bobbin. I’m hoping that this will have a really grunty, slightly overdriven sound. Both sets are protected with paper tape over the coils.

    Again, as this isn’t an attempt at capturing the PAF sound, I pot the bobbins. I use paraffin and beeswax wax in a jar set up as a double boiler. I do this outside on a portable hotplate, not wanting to burn my apartment down. I give them about ten minutes each at a low heat.

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    The wound, taped and potted bobbins are then put into their pairs and placed in bags for now.

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    The baseplates are marked on a 0.81mm sheet of 18% nickel silver…

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    …then cut out with tinsnips, joined together with double-sided tape, filed to shape and drilled.

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  13. Barnaby

    Barnaby Premium Member

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    The truss rod slot has been sitting long enough, so I widen it slightly with a chisel until I get a tight fit.

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    The end of the truss rod is wider and sits in a cavity that I drilled using the eggbeater drill.

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    I put a piece of maple over the end of the truss rod so that there will be extra thickness for the lower cover screw to bite into.

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    I also put a strip of curly maple at the end and plane it flat. A tight, clean fit.

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    Here is the planed truss rod end cover.

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    From here, the first headplate is attached. This is a piece of mahogany that is shaved down to about 2mm, leaving the hollow chamber inside the headstock. Then, a second headplate – a thin, black ebonized piece of about 0.6mm – will be attached. All of this will be invisible after headstock binding, but I’ll know it's there.

    Here is the first plate with the headstock roughly shaped.

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  14. Barnaby

    Barnaby Premium Member

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    The next part of the top involves putting in the pickup cavities, angled to match those in the body. In order to do so, I mark the cavity holes on the underside of the top. Then, I use my angled jig to drill with a 10mm bit.

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    The trick is to drill through until the tip of the bit emerges, then go back the other way. This eliminates tearout. I wind up with eight holes in total per cavity – one for each curve.

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    From here, I use my router plane to cut the sides of each cavity in a straight line, and the wedge to ensure that the angle is correct. It’s slow, but very accurate. Before this, I score the edges of the cavity deeply on the top and bottom of the maple in order to stop potential tearout again.

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    The holes line up nicely with the body.

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    I chisel and sand until I have a decent shape, then screw the top and body together through the tailpiece holes and at the neck where the tenon will go. From here, I use my Shinto rasp to match up the edges of the top with the body.

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    At this point, I mark roughly the areas where I will carve the underside of the top. There are accurate pencil lines and rough black ones. I take care to avoid carving the flat gluing surfaces. I am carving the top for two reasons. First, I want the chambers inside the body to be curved all around, with no flat sections. Second, I think that thinning the top will allow me to tune it and give me a little more resonance.

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    I use my small curved-bottom plane to carve out the hollows. It is very pleasant to use and makes nice little curls of wood.

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    I carve more or less by feel, tapping the top from time to time in order to hear the sound of the wood. The piece goes from making a kind of ‘thunk’ to a more resonant ‘domm’ sound. I work my areas, tapping, carving, sanding a little and repeating. Finally, I have a piece that sounds nice and gives me an in-tune B as its fundamental note. I know the pitch will change more as I sand the top and add the undercutting for the control cavity, but this seems like a good place to stop work for now. I reattach it to the body with the screws and am pleasantly surprised by the change in feel. Suddenly, the body seems somehow ‘alive’.
     
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  15. Barnaby

    Barnaby Premium Member

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    Time to bring this thing together!

    First of all, I need to create an angle inside the cavity. This is done by first drilling my guide holes. These are at seven degrees, which is the average angle on the top carve at this point. Because I drill from underneath, I calculate the offset of the holes based on top thickness so that they emerge at the correct point on the top.

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    I drill them by hand, then start to carve my inside angle with chisels after scoring the shape with a sharp knife. Again, seven degrees to match the top.

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    From here, I then bore the large holes for the potentiometers. I take care to preserve the angle and also to score both sides of the hole to prevent tearout.

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    With this done, I do a test installation to check that there are no issues. I need to take a bit out of the innermost part in order to get consistent angles and height, so I do that, then have a nice angle. I also drill the hole for the switch.

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    That is all for the top – it is no ready to become one with the back. After cleaning both surfaces, I put on lots of Titebond (much easier to use than hide glue). I then simply screw down the top and add every single clamp I have in the house.

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    Now, we wait…I’ll give it two days, as I have a lot of work for my real job tomorrow…

    …aaaand, through the magic of the Internet yet again, It’s done!

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    The top was sanded and scraped a little more to more or less the final carve as well after these photos. Following this, I spent an instructive hour or two with some sandpaper and a block plane making sure that all of the sides were true.
     
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  16. Barnaby

    Barnaby Premium Member

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    With the sides clean and the top mostly ready, it’s time to bring the body to the correct thickness. I want about 43.5mm on the mahogany, so put some blocks on my bench to hold it in place…

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    The top is then planed to the correct thickness all over with a jointer plane. It takes a very short time and is a deeply enjoyable task.

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    From here, the neck plane angle is checked again – it’s very close to 4.5 degrees – and things are sanded some more. I may take off another final 0.5 mm or so later on just to get a really clean surface, but it’s not really necessary, I think, unless there are some bumps or gouges before the finish goes on.

    With the angle worked out, it’s time to cut the mortise for the neck tenon. This is a pleasantly simple process by hand. First of all, I mark the cut.

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    Then, I use a tenon saw to cut down the sides. Note the scraper stuck to the back of the pickup cavity. This protects the cavity edge from potential damage as the saw goes back and forth. I’m pretty careful, but I hit it a few times. Glad that wasn’t the maple edge!

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    With the sides mostly cut (to pickup cavity base depth), I simply use a hammer and chisel to remove the bulk of the waste. Pieces come out in very large lumps, I’m happy to say, and this is a fast job.

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    As I get closer to depth, I mark the edges of the mortise inside the cavity with a chisel for the straight parts and an incannel gouge for the curved. Then, I simply pare away mahogany. I also use the router plane to get an even, flat cavity, although I didn’t take a picture of that.

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    One point about router planes – the blade doesn’t go deep enough under normal circumstances. You have to remove it from the depth setting wheel and lock it to the plane using only the collar – this gives you the extra depth needed. To set new cuts, simply prop the plane up on two thin pieces of card and undo the collar. The blade will drop a tiny amount, then you can tighten and continue at the new depth.

    Here’s the completed mortise…

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    At this point, the body weighs 2.1 kg, or 4.6lb. That’s not too bad. I’m currently hoping that the whole instrument will come in under 6lb before parts go on. With any luck, it will be close to 7.5lb when done.
     
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  17. Barnaby

    Barnaby Premium Member

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    With the mortise cut, it’s time for the tenon. I start by measuring the angle of the neck plane and transferring that to my blank, then cutting the angles and sides of the tenon itself with a Japanese saw.

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    I clean up the tenon with a chisel and block plane, checking periodically. The end is shaped with the Shinto rasp

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    Look Ma – no hands!

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    I have a solid fit and a straight, level neck. Finally, the extra ‘ears’ are glued on the headstock. That’s it for today, although the tenon will need more fine tuning once the neck is mostly shaped.

    [​IMG]
     
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  18. skynyrd67

    skynyrd67 Senior Member

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    If I was HALF the craftsman you are I would be tickled to death. You do some awesome work and make it look and sound so simple. Thanks for posting what you do, it is appreciated.
     
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  19. Freddy G

    Freddy G V.I.P. Member

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    I can't believe it! :wow:
     
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  20. Barnaby

    Barnaby Premium Member

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    Dude! :thumb: You are way too kind. I'm not a craftsman at all, but just a self-apprenticing hobbyist lucky enough to be able to get advice from some of the best builders in the world.

    Speaking of the best builders in the world...:wave:

    I've been doing this one for a little while (obviously). Just burning off stress from work. Even so, it seemed to go a lot faster and cleaner this time. I'm apparently learning something. Slowly, but I'm learning.

    I'm really curious about the hollow headstock. Have you ever given this a try? It seems to go against conventional wisdom, but I thought it was worth seeing what happened.
     
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