Acoustic Guitars Want to Break, Here’s How I Build Them

building an acoustic guitar is a constant negotiation between making the instrument light enough to be resonant and easy to play but also strong enough to not collapse from the roughly 165 lounds of tension the strings exert on the guitar because of this Balancing Act Guitar Building more forly referred to as Luther which personally is a word I feel like I always stumble my way through saying properly is not very forgiving and there are more factors to take into account than when building something like say a dining room table for me these challenges and details are

what's exciting it's the small opportunities to discover something new or put your own twist on a classic design that makes Guitar Building fun plus once you're done with this woodworking project you can make music with it and that's just pretty cool the first of these challenges is probably the most obvious it can be pretty nerve-wracking to bend a set of sides for the first time but when you're working with wood that's hundreds or even thousands of dollars just for the relatively small pieces that are needed I'm not going to lie there's a lot of pressure

to not screw it up but a bending jig like this one from stac which should be available around February of 2024 makes the process much easier and you're less likely to break sides there's currently a pre-sale waiting list for these at an introductory price of about $1,500 for the entire kit on STX site this includes the Bender the controller two heating blankets spring steel SL flats and the Cutaway attachment I didn't use the Cutaway attachment for this build but I plan to build a small cutaway sometime next year probably something like an OM model anyways

check out how smooth these curly Walnut sides came out the trick to not having the sides get all warped and wavy especially with figured Woods is to not use too much water and to let the wood cook for about 10 minutes and then cool the room temperature before taking it out of the Bender if you look at the body of an acoustic guitar from the side you'll notice it's shallower at the neck than it is at the heel some folks like to pre-cut this shape into their sides before bending them but I much prefer to

bend the sides and then set them into a template that has the top and back radius cut into them I then transfer that profile to the sides before heading over to the band saww to cut it out with the sides cut to their rough taper I now need to cut them to their length to do this I set each side into the body mold and I mark my cut lines to give myself every possible advantage to make a nice straight cut with my hand saw I Cobble together a couple of scraps to hang the guitar

side off of along with a twoin one clamp SL straight edge to act as a guide while I make the cut one thing I realize fairly quickly though is I definitely need to sharpen my old fret slotting so nevertheless I made the cut without too much fuss and my little clamps together saw guide worked like a charm with the sides to their proper length ends set back in the body mold it's time to glue in the neck and heel blocks to do this I first put a few of the Bessie micro trigger clamps on either

side of where the neck and heel blocks need to be to keep them from sliding around once they're actually glued in place this worked out way better than I expected I just hope I don't forget about this little hack when it comes time to build my next guitar with a small block plane I begin shaving down the top and back of the sides until I'm close to the line I transferred from my templates then I Mark along the edge and sand each side to its final radius using a 40ft radius dish for the top and

a 15t radius dish for the back to provide extra surface area for the top and back to be attached to strips are glued in place along the inside edges called curing curing also adds a bit of rigidity to the sides and helps them to retain their shape until the top and back plates are able to be glued on I'm using mahogany reverse style curing because I prefer the look of it as opposed to traditional style curing but it really just comes down to personal preference either one is fine next I make a handful of side

braces from a few strips of quarteron mahogany and glue them in place so that they line up with the bracing pattern on the back of the guitar these braces add a bit of additional strength and also help to mitigate cracks from forming or spreading in the sides and here I used my micro trigger clamp pack again to keep these braces from sliding around while they're glued in place with the rim of the guitar wrapped up I now turn my attention to making the back and my first stop is at the bands hul to cut a

few slices from this gorgeous Board of claro Walnut having a drum sander in the shop for task like this really speeds up the process and it allows me to more easily control the grain pattern that's revealed than my previous method of using a router sled and double-sided tape dead I take a few passes off the edges to be glued together at the Joiner before for setting up a simple shooting board from a few scraps of plywood to refine the glue seam I carefully run a long sanding block along the edges of the board until a

perfectly straight edge is produced you can also use a hand plane but this method works just fine as well after a few minutes of sanding I check my results and as you can see this book match is ready to go into the clamps gluing up thin boards like this can be tricky because if you use too much force they'll pop up out of the clamps so one thing you can do to prevent this is just add a couple clamps along the seam to hold things down off camera I sanded the back to final thickness drilled

a set a dow holes that'll come in handy later and trace the outline of the guitar onto the back so while I finish cutting this out and sanding the inside surface of the guitar I want to take a quick minute and tell you about the sponsor of this video stac has been innovating solutions for luers and guitar Tex since 1968 and they stand behind their tools with a simple lifetime promise so if a product breaks wears out or just doesn't meet your expectations send it back for a replacement simple as that I was first introduced

to stac in 2004 during a high school apprenticeship with a local luier and over all these years I've had nothing but great experiences with STX products and customer support you can check out all their products at stack.com or just hit the link in the card above or in the description below so back to this guitar build with the back graph glued in I notched it out with my router where each of the back braces will be located and instead of a traditional paper label I wanted to try something different and I thought it'd be cool

to make the label from a cut off of the soundboard so here we go each of the braces for the back needs to be cut from quarter saw wood for this guitar I'm using Spruce and radiusing them to match the radius I put on the back of the guitar sides earlier with that done I set the back in place on a radius dish and glue in the braces doing my best to keep them perpendicular to the center line of the back before the back plate is done each of the braces needs to be carved and

sanded smooth I remove the bulk of the material with standard bench chisels before crowning the top of the braces with a small block plane and sanding all of the edges up to 220 grit with the back complete I now shift my focus to cutting notches along the back rim where the braces on the back will be tucked into the sides and don't worry these snaggle tooth notches will be covered up in a later step I promise to glue the back on I'm using type Bond 3 because it has a little longer open time than type

Bond 2 and I really don't want to be racing against the clock during this step to line up the back I have two dowels in the body mold that correspond with the dowel holes in the back that I had mentioned would come in handy later well it's later and man those dowels really came in handy this quarter-inch plywood template acts as a clamping call to help even out the pressure from all of those go bars and also keeps them from dinning the back of the guitar once the glue is cured I mask off the top

rim and spray a light coat of shellac on the inside this helps to seal the wood and gives it a little protection from humidity swings but mainly I just like the way it pops the Grain and adds some contrast between the different Woods when it comes to picking out the wood for the top of a guitar there are a handful of common choices mainly varieties of spruce are the most popular but Redwood Western red cedar and even a few Hardwoods such as Kaa and mahogany aren't completely unheard of for the top of this guitar I'm

using a nice booked match set of bearclaw sick Spruce from stac siik Spruce is one of the more common woods used for acoustic guitar tops and lends itself well to a variety of Music Styles I opted for Sika with this guitar because I felt like its creamy like color would contrast nicely against the dark walnut of the back and sides but I guess we'll see how it turns out since the guitar's top is so critical to the tone production and structural Integrity of the instrument I spend a little extra time making sure that this glue

seam is dead on before it goes in the clamps over at the shopbot I set up to cut the rosette sound hole and a slightly oversized profile of the top I'm just using double-sided tape along with a couple of dowels for alignment and a little tip I picked up from my buddy James over at Greg guitar is to use a roller like this one to improve the adhesion when you're working with double-sided tape for these operations I'm running an e/ in down bit from bits and bits I've been using their in Mills for a little

over a year now and I've been really happy with the results they have a wide variety to choose from including tiny 23,000 endmills that are great for cutting fret slots and inlay or even a slogan into a piece of Walnut that's about to get slathered in epoxy anyways if you need some bits from bits and bits you can save a bit on your order just type in Woodshop mic for the coupon codee and you'll save 10 bucks once the epoxy is cured I head over to the band and cut a slice off the Walnut that

the rosette design was cut into and since I don't really want to start this process over again I very carefully PR Ros that free using a putty knife by the way any guesses who that slogan belongs to while you mle that over I'll get on with adding some purling and share some tips on how to not do this the right way adding the center ring of perling was the easy part and using tight bond for this glue up was just fine assuming that I don't glob it on like a toddler during art class with the

rosette in place and firmly seated I trim up the excess purling really quick so that I can throw a bunch of little clamps around the sound hole to hold the rosette in place while the glue cures up to this point things are going pretty well I could have used CA glue to get through this process a little faster but with that approach you run the risk of staining the spruce and I definitely don't want that to happen well here's where I would have done things differently for the outer ring I went with two strips of

purling but since PVA glue has a tendency to swell wood fibers because it's water-based that made installing both strips of purling a bit difficult so next time I'd just go the CA glue route and before you regail me about how I can stain the spruce top I have a trick up my sleeve that I was just too stubborn to use a light coat of shellac will seal up the grain and prevent the CA glue from staining the wood then when you sand everything down that shellac will be removed and you'll be left with just a

nice crisp purling line off camera I sanded the rosette flush and brought the top down to final thickness and preparation for adding the braces I transfer the bracing pattern from this template that I cut on the CNC and then go ahead and rough out all the braces from quarter and Spruce the underside of all the braces will also be radius to match the radius that was added to the top edge of the guitar's sides the first brace for the top that I work on is the main X brace once the half flap is cut and

it's glued up I start refining all the other braces that will be referenced off of that main X brace as each set of braces is finished I glue them in place at the goar deck with the top resting on a corresponding radius template and because I'm selectively OCD I wipe up any excess squeeze out before the glue cures and an effort to keep the inside of the guitar nice and tidy until this project I'd never used a goar deck but got to say I really like this approach to gluing things up especially when there are

lots of Parts involved it's really a pretty simple setup all you need is a frame with a top and bottom that are somewhat Stout and parallel then for the bars you can either use strips of hardwood or these fiberglass bars that stac carries either way we'll get the job done but another thing that I just think is kind of cool about a goar deck is the patterns that are made from all the bars it's just neat to look at to glue down most of the the braces I'm using tip Bond 2 but since I make

my bridge plates out of ebony I like to use tip Bond 3 from what I'm told it's a better choice for gluing oily Woods that can otherwise be kind of tricky to laminate with all the braces glued in place I'm now ready for one of my favorite steps and it's carving the braces even though they're already scalloped they're still pretty heavy for where they ultimately need to be and as much as I like making progress on things quickly I enjoy the Slowdown that's required for this step off camera I notched the top of the sides

to let in the X brace and upper transverse brace all the other braces end up being feathered into the top just shy of the curving so notching for those is not required I left the spreader in place at the waist of the guitar to keep the sides flush against the body mold while the top is glued on and don't worry I'll be able to get that out later once everything is cured and just like when gluing on the back a pair of dowels accurately locates the top and keeps it from sliding around as I clamp

the top to the body with a handful of go bars remember when I said all of those snaggletooth notches I cut in the side would eventually get covered up well here we are Now's the Time this binding router jig really makes the process easy on my first acoustic I cut the binding channels by hand with a perling cutter and it took forever but this jig from stew Mac makes routing The Binding and purling channels not only really fast but also super easy and accurate before the binding and purfling are added the engraft has to be

glued in for this guitar I'm going with a wedge design made from the same Walnut I used in the rosette and trimmed on either side with strips of black white black purfling and this is going to match the rest of the guitar once this is glued in I carefully cut the purling and binding to size and dry fit the piece pieces about 12 times before gluing them in place for The Binding on this guitar I'm going with Ebony and I bent that to shape while using the bending jig when I already had it set up

from bending the sides earlier to glue the binding and purling in place I'm again going with tip Bon 3 because of its longer open time but now unlike earlier when the wood swelling could cause issues because of using a waterbased glue for this process it can actually be helpful if the wood swells a little bit because it can help to fill in any minor discrepancies that may be in the binding and purfling channels and just a quick aside a tape dispenser is super helpful to have for this step with most of the details ironed out

on the body it's time to focus on making the neck I'm going to go ahead and be completely honest I wasn't sure what Woods I wanted to make the neck out of I could see a maple neck with Walnut accents looking good but a walnut neck with mapel accents could also look amazing so I'll just make one of each and we'll see which one looks better with the guitar for a guitar neck you ideally want a straight quarteron blank to work with so if you're making your own neck from a single piece of wood you

want a big chunk of quarters saww material but if you're making a laminated neck like I'm doing here you want to work with Flats on stock that way when everything is glued up you'll be left with a blank that's quarteron if you're not sure what the difference is between quarters and flats Lumber it just refers to the direction of the growth rings when you're looking at the end of a board the growth rings in a flat sound board will be mostly flat where the growth rings in a quarter s board will be mostly vertical some

folks debate just how critical this actually is but given that quarteron Lum is more stable that's the route I'm going to go for my guitar necks at some point I'll likely make a jig for holding acoustic guitar neck blanks to the CNC but for now double-sided tape is going to do the trick with the blank taped to the table I get started Prof profiling the top of the neck as well as cutting out for the trust Rod slot I'll also Mill a couple of grooves for a pair of carbon fiber rods to add some more

rigidity to the neck and I'll drill two holes for some dowel pins that'll come in handy later on before I get all carried away and overly excited and just yank this thing off the table I've learned to take a minute and double check that everything has actually been cut to the proper size the last thing I want to do is try and reposition something by hand without reference Edge or dowel pin to help me line things back up but the good news is everything came out great and I'm ready to profile the back of the

neck before carving the back of the neck on the CNC I first need to cut away the bulk of excess material so after I trace the side profile of the neck onto my blank I fire up the band saww and get to work now if I'd been thinking ahead I would have made this blank just a few inches longer then I could have cut two necks from a single blank guess I'll have to put that on the list of things I hope I don't forget before I build my next guitar one thing that's critical for

the next operation on the CNC is for the headstock to be supported if it's not it'll chatter under the cutter at a minimum I won't get a smooth cut but depending on how bad that vibration gets the neck could completely come off the table and be ruined to support the headstock I made this wedge and and I have the neck clamped to my table saw because it's a large flat surface which makes it an ideal place to accurately tape the wedge to the Head stock back over at the shopbot I lay down a few strips

of double-sided tape where the next operation is programmed to run and I go over the tape again several times with that roller I've already mentioned to make sure it has as good of a hold as possible on the MDF spoil board to locate the neck on the CNC I have a pair of 16inch dowels that are are about a/4 in long and those are going to register in some corresponding holes in both the CNC table and the neck even though this tape has a pretty incredible hold and the neck will be somewhat held in place

with those small dowels I programmed the shot bot to run a little bit on the slow side and to also take shallower passes while roughing out the neck I really don't want to see this thing come loose and get mangled up in the cutter since I sawed away the bulk of the excess material on the neck there's a lot of air cutting during the initial roughing operation all that really means for me though is there's less mess to clean up and less wear and tear on the endmills before having the shot by I shaped all

of my guitar necks by hand and while I enjoyed that process I'm not going to lie it sure is nice to have a net come off the machine that only needs minor shaping and sanding before it's ready to finish well if there was any doubt that the double-sided tape would be strong enough to hold the neck down I'm no longer concerned I was honestly worri worried I might crack this thing pulling it off the table I'm really happy with how the net carve turned out and with that done it's time to knock out some secondary

operations to reinforce the neck I'll be using a couple pieces of carbon fiber in addition to a two-way adjustable trust Rod adding carbon fiber to a neck isn't difficult and it really beefs up the neck's rigidity there are a few things to keep in mind when doing this though one you'll be well served to use epoxy when gluing it into a project and two you really need to scuff up the carbon fiber with something around 100 grit sandpaper so that way the epoxy will have some texture to grab into my go-to for this step is

total boat high performance epoxy it's easy to work with and I've always had good results with their products another thing to keep in mind is to just use enough epoxy to coat the carbon fiber and try to not let an excessive amount of epoxy get down into the groove epoxy doesn't squeeze out quite as easy as PVA glue does so do yourself a favor and go on the light side there has been a ton of work to get us to this point and a lot of the setup and playability of the guitar rides on cutting

the neck joint correctly to make things just slightly more tense at this point I'm only about a week away from when I'm scheduled to deliver the guitar and this is the first time I've used this jig for cutting the neck pocket thankfully though it looks like everything is right where it's supposed to be on the opposite side of the jig I established the neck angle and cut the Tenon where the neck and body connect minor fitment tweaks can be made by hand but the bulk of The Cutting of the Tenon is accomplished here and I've

got to say I'm pretty happy with the results off camera I installed two threaded inserts into the Tenon so that the neck and body can be bolted together next up I'm going to be blending the transition area between the neck and the top of the guitar so that way the fretboard will sit flat against the guitar's top technically this will create a little bit of fall at the end of the fretboard but that's not necessarily A Bad Thing and it'll help to prevent fret buzz when it comes time to set up the guitar with the

fretboard surface of the neck sanded flat to remove any Milling marks left behind from the CNC I'm ready to glue on the fretboard now it's really important to not slather glue all over the truss rod for obvious reasons so what I do is cover it up with a thin strip of tape and bonus points if I remember to remove the tape before the clamps go on so remember those 16inch dowels I used to locate the neck on the CNC well they're pulling double duty because I also use them to locate and hold the fretboard in

place while it's glued to the neck now all I have to do is cover it up with a bunch of my favorite R clamps and go grab a bite to eat while the glue cures since I haven't set up a fixture for the CNC to cut out headstock profiles yet I go about this step a little different than most first I cut out the headstock veneer along with any inlay and then line it up on the headstock where it needs to be I again use a pair of 16inch dowels to keep keep the veneer from

sliding around while it's being glued in place and I set a 3/4 in thick piece of plywood on top as a clamping call this ensures even clamping pressure as the clamps go on other than that you know the drill all the clamps T will possibly Fit Plus one or two more for good measure I bet you didn't think a pine 4x4 was going to play any part in this project did you well stay frosty my friends I can't have you predicting my next moves anyways I need to cut away away the bulk of material from

the headstock and if I want to use the headstock veneer as a guide I need to be able to see it logically taping a 4x4 to the back of the headstock is the perfect solution after the profile is rough cut on the band saw I refine the shape on my oscillating spindle sander another task I still do off the CNC is drill for side dots this is one of those times where no oopsies are allowed to install these little side dots I drop a tiny amount of black CA glue into the hole and then ever

so carefully line up the Pearl dot without also gluing my finger to the fretboard and then I press it in place with a plastic glue spreader one of the last things to do before we get into the home stretch of final sanding and finishing is to drill for the tuners the tuners I've picked out for this guitar are really nice and I cannot wait to get them installed getting the guitar ready for the best possible finish is no quick task after each grit I wipe down the guitar and blow off the work surface to remove

any loose grain Left Behind from the Sandpaper and I work my way up to 400 grit for this guitar I'll be going with a high gloss finish and I want it to be super smooth so before I get to spraying I need to fill the Grain and establish a dead flat surface in the past when I've used epoxy as a grain filler I've squeegeed it on but that requires a lot more time sanding so this time around I'm using a completely different technique I'm basically spreading a thin layer of epoxy on the guitar and trying

to wipe off every last bit of it and no these aren't blue shop towels that will leave you with an absolute mess to clean up these are lintree Kim wipes and I have a link for the ones I used below I'll likely apply three to four coats like this scuff sanding between them until I'm happy with the surface and a quick hat tip to my buddy Ty over at shock the fox for introducing me to this approach over the squeegee method for grain filling with epoxy the last part to knock out on the shopbot is

the bridge I wanted to do something a little different than the standard bridge design that's slightly more than a bulbous rectangle and this is what I came up with I might tweak the design a bit down the road but for now I'm pretty happy with it there are two ways to deal with glue surfaces under the bridge and fretboard I prefer to mask off these areas rather than have to scrape away the Finish afterward to have a a clean transition between the bridge and the top I made an undersized bridge and used that as a

template this will result in just the slightest amount of finish being under the perimeter of the bridge but it's not detrimental to the strength of the glue joint since I don't have my explosion proof ventilation system set up in the finishing room yet and I'm using a solvent-based finish I'll be spraying the guitar outside the downside is the potential for bugs or dust to land in the finish the upside is great lighting and no nasty fumes in the shop maybe when I wrap up my finishing room I can also set up a better way to

spray my guitars too rather than swinging them around on a stick and praying that I don't drop it over the course of two days I applied six thin coats of finish after the first day I level sanded everything before spraying the final three top coats after that I let the Finish cure for 24 hours level sanded again and worked my way up to, 1500 grit before buffing it to a high gloss now if you stand in a cross-hatch pattern like I'm doing here make sure you finish off each grip by following the grain Direction this

will make the scratch pattern disappear against the background of the wood grain when gluing oily Woods like ebony especially for a critical glue joint it's a good idea to rough up the surface with something like 80 grit sandpaper I'm not quite as worried about glue squeezing out with this step because it will easily wipe off the finish so I go a bit more liberal with the glue application here to align the bridge I'm using two e in drill bits because apparently I don't have any E8 in dowels in the shop and I'm using Stax Bridge

clamping call along with a few Sound Hole clamps to evenly apply pressure oh and one quick tip here is to wax the dowels or drill bits the last thing you want to deal with now is a piece of metal sticking out of your Bridge that'd be unique for sure but it's not going to be quite as much fun to play even though this is a bolt-on neck I still need to glue the fretboard down to the Top If I don't I run the roof risk that the end of the fretboard will move around a bit

during seasonal temperature changes or that the lower Frets will buzz when the guitar is played and nobody wants that these Waverly tuners are not only insanely smooth but I absolutely love the open back design the bushings with these tuners press in so you've got to make sure the whole size in your headstock is dead on for a proper fit the only trouble I had was keeping them from spinning around because that headstock was so slick so I ended up laying down a few strips of painters tape to help hold the tuners in place while I

marked the screw locations with an all I then pre-drilled for all the mounting screws and made sure to not drill too deep with the help of a little depth gauge tape flag before putting the tuners back in place when working with small screws applying a bit of wax to the threads will help things go much smoother you can use most any kind of wax really but my go-to is standard paste wax because it's sticky and stays on small thread Reds just a little bit better there are a handful of small tasks left to wrap up

like making the nut and saddle leveling and polishing the Frets and drilling out the bridge for the bridge pins but for now let's keep it simple so we can string it up and make a little music while I was in Nashville I had the opportunity to meet up with a great picker Orin Thorton and he ran this guitar through the paces before I headed off to hand deliver it to the car heart store right on Broadway in downtown Nashville and man did he make this guitar sing so if you're ever in the area go check

it out and let me know what you [Music] think [Music] n