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How to build an oo size acoustic guitar

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  • #31
    Coming together nicely, I think, since I'm not really a guitar maker. the last photo is what?
    . . .JoeB


    • #32
      Hi Joe,
      Your not really a guitar maker YET!!!!! hehehe The last photo shows the top of the clamp jig plate with the clamps holding it down tight with the fretboard locating pin head sticking up through the hole in the clamp plate.
      Last edited by Glenn Jennings; 09-11-2022, 04:36 PM.


      • #33
        Making the neck continued

        Hi Guys
        The inserts have been inlaid into the side of the neck. I used the dremel router to remove the bulk of the wood to within 2mm of the line. I then cut the line with an ultra fine chisel made from a high tensile hacksaw blade. This enables one to make a 1-2mm deep cut into the wood and the spread at the top of the cut with the chisel right down in the cut being around 10 thou of an inch. You can do very close and fine work with these.

        Next came the headstock laminating. I did the back first and made a clamp plate that was a neat fit around the volute on the back of the neck. Having this being a close fit means that the laminate doesn't curl around the volute when you glue it in place and you get a good tight fit. The underside of the laminate was saded to the shape of the volute so that a good fit could be achieved.

        As usual I get as many clamps on it as possible.

        Once glued the holes for the machine heads are cleared out to size. Pilot drilled then filed out to size. This prevents laminate chipping around the edge of the hole.

        The front is done in the same way with the exception I used food cling wrap to cover the clamping plate. This was done to prevent the clamp plate sticking to the glue that forces its way through the Burl wood laminate. This is a common problem with burl woods. This way the job doesn't get ruined trying to remove the well glued on backing plate. The plastic can be easily removed with a scraper when the glue is properly set.

        The sides I cut to shape and use rubber bands to apply the pressure to the clamp plate. Selotape stretched almost to breaking pount ensures a good tight fit on the tapered part of the neck. This veneer was very hard to work with having very little strength so it had to be handled very carefuly to prevent breakouts. I used a super sharp Knife and cut 1mm proud of the line making multiple passes over the cut, and sanded down to size. Was able to control the breakouts better this way.

        Once all the laminate is on it is just a matter of a sand down and a coat of sealer and the neck is more or less finished.
        Attached Files


        • #34
          Glenn, really going great, such craftsmanship.
          Mark N. Akers
          My Etsy Store:


          • #35
            I certainly agree with Mark about the craftsmanship, Are you just stringing us along or does it always take this much time to build?
            . . .JoeB


            • #36
              Hi Mark, Joe,
              Thanks for the nice comments guys!!!

              Making the Neck continued

              Fitting the frets. The fist job is to ensure all the fret slots are clean over the while width of the fret. True oil can drop into these when finishing the fret board so doing a check can save damage in fitting the fret.

              I cut the fret wire to length and clean up the one end leaving the other as that will be trimmed to length when fitted.

              I put a line of titebond over the fret slot the tap the fret into place with a panelbeaters flat hammer. Some use plastic head hammers but I find this works ok. The frets will be dressed when the neck is fitted to the body anyway so not a big deal if there is the odd very slight ding in the fret though this hasn't actually happened on the 3 I have built so far.

              I clean off the excess glue trim the end on the fret the dress the edges so that the hand slides smoothly up and down the neck without catching on any of the fret ends. And that it.

              With all the laminating done and one last coat of true oil to go on. The only thing left to do is fit the machine hreads , Glue on the wings at the top of the headstock and fit the truss rod cover plate which is one small screw.

              The neck is now for all intents and purposes completed.
              Attached Files


              • #37
                Making the body mold to fit the sides and end blocks to.

                The mold is made of 4 sheets of 18mm medium density fibre board and each board is marked with a centreline.

                I lay carbon paper over the board and tape the plan in place over the carbon paper then trace the pattern onto the first board Making sure the plan centreline matched the board centreline exactly .

                Using the band saw I cut out the shape and sand it to remove any bumps and check that the cut is square all the way around.

                Once satisfied that this is all good I lay this board over the other 3 making sure the centre lines are spot on then trace around the edge with a pencil to give me the shape. Is a lot quicker than scribing each one. They are then cut out. I stager the cuts so that I dont end up with a split right up the end of the mold. The bandsaw makes a 60 thou cut so I make a spacer to be glued into each cut prior to shaping it all when all are pinned together.

                I then clamp the first one I cleaned up to one of the others again checking that centre line is spot on Then dress the roughed out one to match the first board again checking they are square across the cut.

                I then clamp all 4 boards together with the two cleaned up boards on top and bottom. Again checking several times thatall 4 centrelines are spot on with the square. Use the square as slight variations can give you progressive error over the 4 board line ups. You could be a mm 1-1.5 mm out.

                I then pin all 4 boards together to secure the location and take off the clamps. I then screw all 4 boards together at about 3 inch spacing all the way around the mold.

                With that done the the two inside boards are dressed to fit the top and bottom board. Doing it this way prevents progressive error giving you a funnel shaped mold which then takes a LOT of work to get squared up.

                With the mold now made I trim the sides so clamps can be fitted to blocks to press the wood into the shape of the mold when it comes to final fitting of the sides of the guitar.

                Finally I drill 10 holes on each side for screw clamps to hold the top and bottom of the guitar to the sides in the mold. In the photos you will note that these clamps have a felt wad to prevent ding in the edgeof the guitar top and bottom as it is clamped into place.

                And that is the mold completed.

                Next step is to steam bend the sides, fit them to the mold and glue in the dovetail block for the neck and the block at the other end of the guitar body These blocks when glued hold the sides together and complete the sides of the guitar body.
                Attached Files
                Last edited by Glenn Jennings; 09-17-2022, 11:16 PM.


                • #38
                  Hi Guys
                  Neck is now completed.

                  How to make a guitar top

                  First step is to select the wood which in this case is Tanekaha which is a new Zealand Nativer timber. This has to be thinned to 0.11 of an inch or 2.8mm.

                  Having selected the top we now make the bracing to go on it out of Sitka Spruce. The wood needs to be quarter sawn to get maximum strength into the brace. If you can't see the parallel grain lines running the full length of the top edge of the brace then you have cut it the wrong way. I check the shape frequently as I sand these to shape against the plan drawing to be sure the subtle curves on the underside of the brace are all in the right places. These when glued in put just a little tension into the top.

                  The braces will then be glued to the top and when well dry the top will be tuned and the braces shaped to give the best tap tones that one can get from it.

                  This is done until clean clear notes are ringing from all different spots on the top. The more clear but different notes you can get the better the response will be when played. I will also be looking to get a little flexibility in the top and will trim the braceds until I get that. If I get it right the top will ring like a bell when tap test is done.
                  Attached Files


                  • #39
                    Hi Mate, Been watching your Step by Step Process and Decided that it is the Way I would do it.Yea!! Right . Ha,Ha. Gona be a Beautiful Piece. Merle


                    • #40
                      A little late with any comments. Dang man, when you get this finished, you're going have to play it in the closet, or someone will hit you over the head and take it from you. This is going to be a classic, no doubt.
                      . . .JoeB


                      • #41
                        Hi Merle, Joe,

                        Thanks for the nice comments guys. I'm letting the fancy grained wood be the artwork on this piece.

                        Beginning to have my doubts about the Tanekaha as so far it doesn't have that great a tap test. Sounds a tad flat. will change a lot when all the braces are fitted and tuned. It does have a bit of a ring to so I hope I can build on that.


                        • #42
                          Wow Glenn that wood on the neck is absolutely beautiful, very nice job.
                          Mark N. Akers
                          My Etsy Store:


                          • #43
                            You are truly a craftsman Glenn! I second Mark, that is a beautiful wood.
                            We live in the land of the free because of the brave! Semper Fi


                            • #44
                              Tap test, I always had a hard time choosing which beer I wanted also
                              . . .JoeB


                              • #45
                                Hi Mark
                                Have to agree the grains in the wood. It is realy nice wood.

                                Hi Randy
                                Thanks mate, Is more patience and attention to detail than craftmanship. Anyone could do it if they really wanted to.

                                Hi Joe.
                                I never have a problem choosing a beer. I just start aty one end and work my way through the lot. hehehe

                                How to maske a guitar top continued.

                                First the wood has to be sanded down to a thicknes of 2.8mm. Planers can get it down to about 4mm by pacing a plank over the wood as you feed it through to keep it from whipping about but after that it starts getting dodgy.

                                I use a 40 grit belt in the Ryobi benchtop belt sander and just keep working the wood over the belt using a flat piece of wood with a handle on itto keep it flat against the belt as as friction builds up a little heat the wood wants to curl a bit.

                                Once sanded to 2.8mm the tricky part is getting a good join. I get the edge dead square by holding the wood against a perfectly square lage block of wood which is placed on a dead flat sanding bed. This creates the perfect right angle and I just slide the wood back and forth until a perfect join is achieved. To check hold both pieces together on a window pane with good light behind it. If you can see light through the join it isn't good enough.

                                Next thing is to glue the 2 pieces together. Whis is a lot harder than it sounds as clamps tend to bend the wood so the join is no longer square.

                                To get around this I used 3 sash clamps. I place the wood on a dead flat bed and place the clamps over the top. I glue the wood and Push the two pieces together by hand then tighten up the clamps until the slightest bow shows in the wood. I then use polystyrene wads under the clamps which pushes the wood down flat then just the smallest tweak on theclamps to make sure no more glue presses out and that is it.

                                This is a tricky process and a lot of FEEL is involved. But it is worth the time spent as this join is probably the most critical in the whole instrument as the top determines more than any other piece, how good the instrument will be.

                                With the the sides glued and sanded the rosette around the sound hole can be done . I use a dremel router and a special radius tool that rotates around a spindle sunk into a piece of dead flat fibre board to cut the channels for the purfling. The spindle goes through the exact centre of the sound hole.

                                I cut the channels to be a neat fit and glue the purfling in with Tightbond glue. Pre bending the purfling is a good idea as it shows any weak spots BEFORE you glue it in place. If it breaks half way around it can be tricky to fix and best to be removed and try again.

                                Once inlaid I sand it all flat then use the router to cut out the centre hole. NOTE the joins in the purfling will be covered by the neck.

                                The bracing can be fit. I lay the plan over the top and transfer the bracing pattern to the wood. Each bracwe id checkedthat it is a tight fit on the wood top. I use a piece of news print paper which is about 3 thou of an inch thick as a feeler gauge . I sand the braces until they fit then glue them in.

                                With the braces all in place the top can be tuned which involves trimming the bracing to get the best sound from the top. One holds the top in various points and taps the top to see what sounds you get. Rather that write a book about it see the link below for the procedure.

                                The tanekaha wood was sounding quite flat to start with with the bracing fitted and the top tap tuned I am now getting a lot of different clear notes ringing from it when tapped. It turned out a lot better that I thought it would. I am optimistic of a good outcome from this.

                                Attached Files
                                Last edited by Glenn Jennings; 09-22-2022, 08:33 PM.