Post 34: Thinking of a headless and fretless bass

   I would like to use that wonderful piece of canari wood to try my hand at making a more traditional wooden bass. I want it to be special in some way.

   I considered using 5 single tuners to make it a 5 strings long-scale bass using extra long strings, possibly pushing the scale to 38". But then I ran across a really nice set of tuners and string locking nut on Amazon for only $35.99... I was not expecting much, but it turned out really nice and solid, and I decided to use it and go for only 4 strings. 

    On top of that, the way the individual bridges are designed, I could with minor modifications place a piezo pickup right under them. All I had to do was to cut 2 slots on the sides to accommodate the width of the piezo and one underneath for the wire:

   I had first made a rough mockup in Photoshop:

So I more or less reproduced it full scale on a large piece of poster board, straightening the original slanted design

     I will be refined as I look at it over a few days and fiddle with the shape, probably shrinking the body some.

    The length of the neck will be determined by the length of the strings, and I want big strings, so I ordered a set of 5 D'Addario Xtra Long flat-wound bass strings,  of which I will only use the 4 bigger ones .65, .80, .100 , and .132.

Post 33: Ready for further tests

  I took the instruments completely apart to bend the end of the neck back, and then reassembled it and restrung it with a new set of flat wound strings in diameters .26, .36, .46, .59, .70, .85, and .105.

  The tuners ended up being too hard to adjust by hand, I will need to change the thread of the screws to a smaller one, probably using M4 metric screws fitted to the knurled knobs.

  I gave it to my friend LaDonna to play with and test for a while.

Post 32; Stringing the guitar

  After the first full springing test, I realized that both the nut and the bridge were too high, the frets to quite level, and that the neck was not as stiff as I thought.  I needed to add a pair of truss rods to counter the pull of the strings. 

   I cut two brass half-moons that I attached at the neck and at the bridge with 3 large screws. 

        Two M4 stainless steel rods connect them and long nuts at the end of the neck allow adjustment

      Once these were installed and loosened, I put the guitar back together. The fingerboard was attached with double-stick tape. I gave up the idea of a bridge with adjustment for intonation and instead cut and shaped a slim piece of bone. The ebony was shaved to be level with the brass holders in order to lower the bridge as much as possible. A groove was cut in it and the bone strip was attached with epoxy. 

      

     The brass nut was cut down and attached to the neck with two small screws. The two side strings were installed, the position of the grooves for these two strings marked on both the bridge and the neck, ans shallow grooves cut. 

   I tightened the truss rod some, and then some more as the rest of the strings were installed and roughly tuned. The spacing of the strings was marked and grooves cut for the rest of them. They were still too high both at the bridge and the neck and the grooves were progressively deepened till I was happy with the action.  I will fine tune it later. notice the 1/8" aluminum at the end of the neck is pulled up by the tension of the strings. I will need to bend it back some to make it stiffer and compensate.

        A test showed that both the piezo pickup at the bridge and the magnetic pickup work fine with an acoustic guitar preamp.  However, the bridge pick up is very sensitive and picks up taps on the body and finger sliding noise on the round wound test strings. So I ordered a set of flat wound guitar strings and a set of bass strings in graduated sizes.

        Instead of a switch between pickups, I decided to use two pots to control the mix progressively before running the signal through the preamp, which is attached to notched pieces of aluminum glued with cyanocrilate.

Post 41: First Stringing It

   I have been trying to decide for a while how exactly to design the tuners. There are basically two options with a headless guitar:

            1)  Thread the string thru a hole at the head and have a screw on the tuner to secure the string.

           2)   Thread the string thru a hole in the tuner and attach it with a screw at the head.

    My original intention was to go with #1, and I made several possible tuner heads.  But the idea of the head simply having 7 holes instead of an anchoring block sounded attractive, so I made a tuner with a screw to attach the string just to see.  The basic brass blanks I cut for the tuners can be fashioned either way once I finally make up my mind:

    I also worked on the bridge unit: cut an ebony base plate, cut out a rectangular notch for the wide piezo flat sensor, attached it with two brass screws to the guitar top, finished shaping and polishing the two brass side pieces, cut  a wider strip of ebony to fit the sensor, and glued the two brass strips to the base plate with cyanoacrylate glue. 

     I then made a bone blank for the nut, drilled a hole at the head, and strung the middle string for a test.  

          I wrapped the other end of the string around a screw in the tuner head, tightened it, and stretched the string. It worked. 

          The following picture shows a close-up of both the bridge and the tuner. There will be a bone strip inlaid in the ebony to hold the strings, and since that strip is wide, I want to come up with a way to adjust the intonation using seven separate adjustable bridges.  There are several ways to do that: cutting 3 long parallel grooves in the ebony to fit thin bone strips or cutting seven dovetail grooves where matching bone bridges can slide for finer adjustment.

       The string is too high both at the nut and the bridge and I will work on that later. But first, I wanted to know if the piezo worked and what the sound was like, so I connected it to my big amp thru a preamp and was pretty satisfied. For a reason I cannot understand yet, the sound is soft when the string is plucked down, but much sharper when the string is plucked up. I can only guess it has to do with the fairly sharp angle of the bridge in relation to the strings.

Post 40: Finishing the fretboard

    I worked on the fretboard for the last couple of days, deepening and widening the cuts for the frets, first using the very thin saw I started the slot with , then a slightly wider blade Japanese saw, and finally with my "proper" fretboard saw. There is no depth gauge on the saw, so I just draw a line on the blade with a black Sharpie about 3/32" from the teeth. 

    I then make sure the depth of the cut is sufficient using a section of fret wire on which I sanded off the barbs of the kerf.  The frets are cut slightly too long and then hammered in with the mallet on the anvil. I didn't use any glue, I believe the ebony is hard enough to hold them. I hammer the edges especially hard, and then bend them in some more and blunt them with a small brass hammer. 

     Fingers crossed!

        After sanding the ends of the frets and rounding them with a fret file, it is actually beginning to look pretty good, with the large brass dots matching the fret color:

         I will do some more filing and sanding, till it is as smooth and "perfect" as I can achieve with my limited skills and tools. I still need to check the frets are level, try to get them level with the mallet, and possibly sand them level if absolutely necessary.

Post 39: Sanding the fretboard, AGAIN

     Well, I was not satisfied with the fretboard. The 13" radius was fairly constant all the way down, but it wasn't perfectly flat. The ebony board has a slight curve and some flexibility, so I drilled 3 holes in the fretboard where dots will go and screwed it to a flat piece of 2x2. I used a perfectly straight board of padouk as a flat base for a long strip of 80-grit sandpaper I attached with double-stick tape.  I could clearly see the shiny low spots as soon as I started sanding the fretboard:

      I kept sanding till all the shiny spots disappeared. The resulting fretboard has a radius varying from 13" at the nut to about 15 or 16 at the other end. It is actually a good thing as that will allow for a flatter bridge. It's now time to place the dots and sand them down level with the fretboard.

     Speaking of the bridge, it will need to be quite low, so I plan to recess the two piezo sticks into the 1/8" aluminum top, cutting a slot in it and adding a small 1/8" aluminum plate on the backside. That will require taking the built apart and making a small notch in the through neck. 

    I will also cut a back panel for the body to match the front panel and attach it when I reassemble the body, including the pickup.

Post 38: Neck stiffener, fingerboard

      Well, I found a third option and used a piece of U-channel aluminum I had as a stiffener for the neck where the cutout for the pickup weakened it. The 2" brass screws I got, because that was all they had, came in handy to bolt the reinforcement on.  I had to cut down the channel at an angle for them to be long enough. In fact, they are long enough to add a 1/8" aluminum back panel to the guitar later.

      I went to Woodcraft yesterday to look for a nice piece of wood to use as a fingerboard, and ran across a  slab of woof I fell in love with.  At 14 board-foot, it was expensive, but I asked and got a nice discount.  I have been toying for a while with the idea to make a wooden electric bass, and this 16" x 8ft slab of Canari Wood is big enough to cut 3 guitars out of:

      It still has some bark on it, and I love the white outer wood and the colorful orange and yellow sshades of the heartwood. 

       I can visualize gluing two pieces together so a white stripe runs through the center of the guitar body and cutting a Stasi-inspired mini bass out of it:

          But that is for another post. In the meantime, I cut and shaped a piece of ebony from Woodcraft for the fingerboard with an 13" radius.  In order to get the proper radius, I used an aluminum template to scrape chalk I had rubbed on off the fingerboard to show high points and so sanded them down progressively. 

       Before I was quite there,  I marked it and slotted it for frets. The last time I did that for the lap steel, I used a miter box because the frets were straight. But the frets are slanted on this one, with a scale varying from 732mm to 768mm. So I just marked each fret end as precisely as I could with a knife mark, scored a deep fret line with a knife, and followed it with a thin fret saw:

          Here is how it looks on the baritone body with the black 7-string headless guitar locking nut and the piezo bridge roughly in place. I will use a thin piece of ebony as a spacer under the bridge instead of the oval piece of aluminum :

Post 37: Cutout for magnetic pickup, bent tuners plate

     Today I cut out the hole in the front plate to fit the magnetic pickup and notched the neck tube to fit it in. 

       I also bent the part of the front plate where the tuners will be attached. I then cut an oval aluminum plate to fit around the bridge pieces. It looks like the tuners could be moved closer to the bridge, within the body shape. The wooden bridge will have to be flattened and raised to match the aluminum fingerboard.

     I tested the flexibility of the neck and there seems to be some give, probably because the notch for the pickup ended up deeper than expected. There are two possible options: add square tubing sections bolted on each side of the notch in the neck to stiffen it. The other is to install two truss rods.

Post 36: New tuner design for the 7 strings, neck bolted on

      The tuner I first made was functional, but I thought a slicker design would look better, so I made another one I liked better. I also made a brass angle piece to anchor it too which is thinner than the aluminum angle and will give it a tad more travel:

        I received the 12-24 x 2" flat-head brass screws, and used them to attach the aluminum neck to the aluminum guitar "body".  I made sure to mark the position of the dots on the 75mm scale and keep the screws off those areas in case I do the same as with the bass and use the attaching screws as the dots:

       The resulting assembly is extremely stiff, so there is no need for a truss rod at all.

Post 35: Back to the 7 strings guitar

      I received the 7 strings pickups yesterday. I plan to use just one mounted directly recessed into the body at an angle with no plastic trim. I will cover it with a fitted brass plate

     I finally bit the nail today and cut out the aluminum blank for the body. I refined the shape sanding the edges.

I also came up with a better fanned-out layout for the 7 tuners. The section of the body they will be attached to will be bent down at an angle as explained in the last post. I am not sure yet whether the trapezoidal sliding parts of the tuners will be made out of a U-channel aluminum or cut out of solid brass.

     The section of 2" aluminum tubing will have to be thinned out some more before I attach it to the back of the body front plate with nine 1/4" screws going all the way through the back of the neck, and then cut off and sanded smooth, showing as 9 brass dot. I believe the guitar will not have a back, just a box covering the preamp, pots, and wires. The wires from the piezo and from the magnetic pickup can be routed through the neck.

       I made a tuner slider out of solid brass, and believe it is the way to go. I will make them a bit wider, out of a 1/2" x 1/2" brass bar I just bought at Metal Supermarket, and then cut them as wedges so they fit together nicely when fully extended.

       The next questions to resolve have to do with the kind of fingerboard:

               Do I fret it or leave it fretless?

               Do I make it out of wood or aluminum?

               Do I leave it flat or make it curved to match the bridge?

       I have a piece of 1/4" Padouk (barely thick enough) and a 5/16" ebony blank (not long enough for a 30" scale). If I use wood, I will need a truss rod of some sort.  

       I have a piece of 3/16" aluminum that could make a "floating fretboard" like the one on my long bass that is bolted over the neck at a slant with adjustable spacers. 

       Would it be possible to form it into a curve? Actually, a piece of 1/8" aluminum would be easier to form and the curve would give it the required stiffness. I need to try on a scrap.

Post 34: Thinking of a wooden 5 Strings Bass

      I like the look of those Stradi basses so much I am entertaining the idea of actually making a fretless wooden bass along those lines, even though I lack the professional woodworking equipment. 

     I happen to have a well-seasoned plank of Padouk about 4"W x 48"L x7/8"T.  That is long enough to make a one-piece body, using lighter wood for the sides of the body. 

     Ttuners must be underneath the body, as the neck ends this way:

     Here are some other examples of designs I particularly like:

      I will let all that mature a few days before I start sketching. I may run by Woodcraft to see what light-colored wood they might have in stock to make the body out of. 

Post 33: Exploring designs for the Aluminum Barytone Guitar

   I have spent a good deal of time in the last week or so exploring unusually creative guitar design on Pinterest, and have seen some great stuff made of wood. There are plenty of amazing custom guitar shops. One that really stands out for me is Stradi, out of Poland. They have been around for 20 years, and the stunning sophisticated simplicity of their bass designs is truly admirable:

     But as much as I would like to design and build something along those lines, I have neither the uber craftsmanship nor the woodworking equipment to do so. I better stick with my aluminum and brass rough look. I am even reconsidering using padouk sections for the body I designed. 

   But I happened to have a chuck of brass with a nice half-curve to it and Stradi inspired the idea of a slick curved piezo bridge. I finished the curve, sawed the 3/4" piece in half, and shaped the two sections with a sander. I cut and shaped a 1/4" piece of padouk to make a bridge. It's still rough, but once smoothed out and bolted to the guitar body, with two piezo sticks under the wooden bridge, I should get a good signal:

        Of course, to use that bridge, I will have to make a fingerboard with a roughly 12" radius for 7 strings or settle for 6 strings and use the ebony one I just bought on sale:

       In that case, I would need to make another matching bridge out of ebony.

      An issue I am working on is whether to use a truss rod to have some adjustment on the neck if it bends, which I doubt. But it is possible if it pulls on two brass pieces bolted to the 1/8" aluminum top itself.

     To get enough pressure on the piezo bridge, the strings need to make an angle of roughly 20 degrees, so the tuners will have to be mounted at a 20 degrees angle. I made a side drawing of the guitar:

        Another issue is whether to use the Chinese tuners I ordered:

or to make my own using some 1/2" brass thumb screws I have. I made a proof of concept mockup by bending a piece of the 1/8"aluminum, which was actually quite difficult. That stuff is stiffer than I thought. They have to be staggered and spaced precisely so they are as close as possible but do not touch. I tried to bend the little pieces at a right angle, but the aluminum broke. So I had to cut little sections of a 3/4"x3/4"x1/8" aluminum angle molding and attached them with M3 socket screws. The sliders to which the strings are attached will be made of brass and tapped to match the 10-32 thumb screws. Each tuner unit would end up being wider than the commercial ones, which means they will need to fan out slightly and the strings will require spacer posts: