Better Bolt Bridges – Left-handed Thread Rod

Posted on July 29, 2017 by junkshopaudio

Better Bolt Bridges – Left-handed Thread Rod

I had been struggling with keeping my floating bolt bridges in place for proper intonation. I would set the bridge perfectly, as pictured below:

However, over time, the vibration of the strings would eventually turn the bolt, thus throwing my guitar out of tune, as pictured below:

If you look at the first picture, you can see that the orientation of the string is strained as it fights to stay in one of the thread slots. The force that the string places on the bolt naturally moves the bolt into a position where the string sits comfortably within a thread slot.

Even bolt bridges that are mounted into a slot suffer difficulties. However, since the bolt can not turn to orientate the threads with the strings, they are more prone to slipping into another thread slot, which leads to intonation and string spacing problems. Plus, a string sitting on top of threads allows less usable surface area than a string seated within a thread slot.

The solution showed up on my doorstep yesterday morning. I had been trying the figure this out when I recalled that, in my warehouse days, contractors would request left-handed thread rod for certain jobs. I looked around and found 3/8 left-handed steel rod at Fastenal for $26.87, plus shipping, which seems pricey, but I can cut about 36 2″ floating/fixed bridges for $1.08 each.

This is the direct link to the rod that I purchased: https://www.fastenal.com/products/details/47304

Here is the result. As you can see in the image below, the floating bolt bridge is once again in tune; however, this time the strings will not cause the bolt to turn because the strings are now seated comfortably within the thread slots.

Tragedy averted—now I just have to find some left-handed brass rod.

Thanks,

https://www.junkshopaudio.com

PVC Bamboom Stick

Posted on July 28, 2017 by junkshopaudio

PVC Bamboom Stick

The handle on Bennet’s Bamboom Stick failed during its first use. Bamboo is strong for its thickness, but, in addition to the handle, the frame cracked in four places, while I was cutting and shaping the instrument. The cracks were easy to fix with glue and clamps, but I’m not sure how it will hold up over time. Surely the handle will hold up with the addition of a dowel, but there was still reason for concern.

This led me to look for a more resilient material. PVC is strong and flexible and easy to manipulate. 1-1/4″ PVC pipe is an excellent size for the body and 1″ is perfect for the handle, as 1″ PVC fits close inside of 1-1/4″ pipe.

For the handle slot, I made horizontal cuts on the body with a hacksaw and then used a 1-1/8 spade bit to remove most of the material on the front and back of the frame. The rest of the handle slot was shaped with files. I cut the handle from a 1″ piece of PVC; it fit snug within the opening. I also slipped a piece of 1″ wooden dowel into to 1″ PVC to reinforce the handle.

I cut the pickup hole in the same fashion that I shaped the handle slot. Much like the bamboo version, it allows limited range, but a bit more room to install the piece of angle that would hold the simple tuner and the 1/4″ jack. The wall of the 1-1/4″ PVC was too thick for the nut on the 1/4″ jack to fit, so I filed down the outer side of the frame, around the hole, until installation was possible. Although it appears ugly, I have started using hot glue to strengthen my solder joints; it keeps me from having unexpected delays.

To create more clearance at the front of the handle, I cut down a 1″ cap and glued it to the front portion of the handle. I filed a small triangular notch into the top of the handle and used a screw to tighten the string down. A binding screw worked well to allow the handle to pivot. I added an eye bolt, bent to an angle, to act as a nut and to set a consistent action. For this PVC version, I decided to use heavier eye bolts than I used on the bamboo version to further strengthen the instrument.

Because of the limited space, I had to set the piece of angle, then install and solder the jack to the pickup, then install the bent eye bolt, and finally, set the pickup in place. In this PVC version, the JSA Nd144 pickup sat loose in the hole, so I cut and shaped a small piece of 1″ PVC to fill the space. I filed the inner sides of the 1″ piece of PVC until the pickup fit snug. After that, I added the usual simple machine to set the open note/octave.

I added two 1-1/4 jacks to the top and bottom of the frame and a 1″ cap to the back of the handle. For the bottom, I installed a screw-on rubber bumper so that it doesn’t slide on the floor. Additionally, I left the remaining string intact, since there is no easy way to keep the instrument grounded. The jack is grounded to the bridge eye bolt, so one must simply hold the remaining string against the handle, while playing, to keep a constant ground.

Just like the bamboo version, there is only one E string, but the instrument has a lot of range. I added a simple tuner so that the player can set the open note/octave. The player controls the pitch by tightening and slacking the string with the handle and there is definitely a learning curve, as the player has to listen for the note correct pitch—I place the difficulty level somewhere between playing slide guitar and trombone.

It seems important to note that when I tested this instrument the string broke rather than the frame or handle.

Check out this quick and thoroughly awful video:

Thanks,

Bennet’s Bamboom Stick

Posted on July 19, 2017 by junkshopaudio

Bennet’s Bamboom Stick

“Bamboom” was how Bennet used to pronounce “bamboo” when he was younger. In Army of Darkness, Ash called his shotgun a “boom stick”—no real correlation, just a fun fact.

This instrument was commissioned by Bennet. I can’t remember what it is really called, but Bennet fell in love after playing one at the St. Louis Cigar Box Guitar Club. Both the frame and handle are constructed entirely of bamboo. The one that he saw included a cigar box and piezo pickup, but I wanted to streamline the design, so I cut a hole and installed a JSC Nd144 electromagnetic pickup.

Bamboo is incredibly strong for its thickness and weight, but it is easy to manipulate once a hole is created. I made horizontal cuts with a hacksaw and then drilled a couple of holes, where I wanted to cut vertically, and sawed a half inch strip out of the center. After that, a sharp chisel cut the rest relatively easy, with a surprising amount of control over how much material was removed.

I cut a handle from a smaller diameter piece of bamboo; it fit snug within the opening. Build note: if you are thinking about constructing a similar instrument and use a bamboo handle, consider reinforcing the handle with a piece of dowel rod. The handle on this instrument cracked during its first use. I’ll just remove the twine and then glue and clamp the handle on Bennet’s, but it’s better to reinforce the handle from the start.

From the pickup hole, I had limited range to place the piece of angle that would hold the tuner and the 1/4″ jack, but that was the only access that I had without creating more holes. It was tight, but it all fit without interfering with the connections.

I filed a large rectangular notch into the top of the handle and use a 1/4″ bolt and rod coupling to tighten the string down. A couple of brass pieces and binding screw worked well to allow the handle to pivot. I also rounded out the back of the frame to allow the handle more range and added an eye bolt, bent to an angle, to act as a bridge and set a consistent action.

Because of the limited space, I had to set the piece of angle, then install and solder the jack to the pickup, then install the bent eye bolt, and finally seat the pickup. I was extremely happy that it all worked the first time. After that, I added the usual simple machine to set the open note/octave.

For the bottom, I added a screw-on rubber bumper so that it doesn’t slide on the floor. I fit perfectly, with a little persuasion.

There is only one E string, but the instrument has a lot of range. I added the simple tuner so that the player can set the open note/octave. The player controls the pitch by tightening and slacking the string with the handle and there is definitely a learning curve, as the player has to listen for the note correct pitch—I place the difficulty level somewhere between playing slide guitar and trombone. Good times.

Thanks,

Shakespeare Hardback Book – Three-Stringed Electric “Cigar Box” Guitar

Posted on June 23, 2017 by junkshopaudio

I had a crazy idea to make a book into a guitar and this is the product. It took a while to find the right book, but eventually I landed on this copy of the Complete Works of William Shakespeare. It was a mix of the correct size and thickness; plus, it’s Shakespeare.

I did some quick Internet research and didn’t see any other “book guitars”, so I assumed I was in fairly uncharted waters. I took some time and thought about how I should best proceed. In the end, a straight edge and razor blade seemed the best course.

I would be lying if I told you that the first cut was easy. I’m not in the business of destroying books, but…

I found the center of the book and measured the width of the neck wood. Then, I taped it off and drew the lines. I cut out the side first, to the depth of the neck, and then cut the center to the same depth. After the center was removed, I set the temporary neck in the center and replaced the side pages—everything fit great.

Next, I fastened the outer pages to the back cover with some flat, low profile bolts. I drilled through the pages and back cover, installed the bolts, and then chiseled a small area on the inside of the front cover to allow for the other end of the bolt. Now, the pages wouldn’t fall out and it would be a secure area for the electronics.

I cut down the neck, glued it, and carved the Double Razorblade head design that will be my official Junk Shop Audio head going forward. I cut a channel for my Junk Shop Audio Nd144 pickup and stained the neck with a steel wool and balsamic vinegar blend that looks awesome.

I fastened the neck through the back of the book with flat furniture bolts. These bolts come in a variety of colors and are strong—the neck was firmly attached and the bolts looked cool.

To hold the pickup in place, I used some metal scraps from the 9v adaptor deconstruction. I lined them up on the neck, grabbed them with a length of duct tape, and placed the tape in the correct area on the back of the book cover. the magnets on the pickup will attract to the steel scraps.

I cut a hole for the 1/4″ jack and a small channel between the jack hole and pickup for the wire.

I installed the small piece of angle with three brass screws. and then added the simple machines—made of ground thumb screws and rod nuts—and a bridge made of a cut bolt, filed flat on the bottom.

For the head, I used stainless bolts, brass washers, and brass knurl nuts to hold the strings in place and a cut bolt for the nut. The frets are drawn on in pencil, because I may add a fretboard and frets in the future.

Acoustically, the guitar sounds louder and more bassy than I thought it would; amplified, it sounds really dirty when you kick in the overdrive.

Check out this quick and dirty video:

Thanks,

Cecil Whittaker’s Pizza Box Guitar

Posted on June 21, 2017 by junkshopaudio

I had this clean Cecil Whittaker’s Pizza box, so I strung it up to see what it would sound like. I cut down the neck, glued it, and carved the Double Razorblade head design that is now the official Junk Shop Audio head. Then, I cut a channel in the neck for my Junk Shop Audio Nd144 pickup and stained the neck with a steel wool and balsamic vinegar blend that looks awesome. The old looking strap came with my Jay G. parlor guitar; it seemed to match this build well. I made a strap adapter out of duct tape, which works well with the disheveled theme.

I cut a hole for the 1/4″ jack, along with removing part of the inner box. The jack works great, but care must be taken when inserting and pulling out the cord, as the wall is a bit weak.

I installed a small piece of angle with three brass screws. and then added the simple machines—made of ground thumb screws and rod nuts—and a bridge made of cut brass rod, filed flat on the bottom. To hold the box closed, I used the strap button, which is made of a brass knurling nut and a vandal-proof bolt—when this is removed the box opens.

For the head, I used stainless bolts, brass washers, and brass knurl nuts to hold the strings in place and a cut bolt for the nut. For the frets I went in a new direction—after marking the fret distances, I cut small grooves into the top corner of the neck to mark the fret positions. These small grooves can be seen from both the front and side, so it is visible from all angles. I like the subtle look of these markers.

Acoustically, the guitar is not super loud, but it’s great for jamming out in the driveway after hours; amplified, it sounds great.

Thanks,

Fireplace Pan Electric Guitar

Posted on May 17, 2017 by junkshopaudio

Fireplace Pan Electric Guitar

I found this old brass fireplace pan at my local antique mall and immediately saw potential. The wrought iron handle seemed like it would accommodate two strings and it was long enough to provide a reasonable scale.

I based the scale and fret spacing off of my son’s 19″ Zakk Wylde Peewee Les Paul, which was about as far as I could push the space provided. I used the rim of the pan as a bridge and, even then, I only had about an 1-1/2 of usable surface behind the nut.

As usual, space was tight; therefore, traditional tuners were not a viable option. Using the rim as a bridge, I installed the tuners down the side of the pan and my simple, linear machines were perfect for the space available. These tuners are cheap, efficient, and adaptable—many of my past projects would have been impossible without the flexibility offered by these machines. I placed the 1/4′ jack in the upper right instead of the lower right, because the protruding cord would be the least obstructive and it could double as a makeshift strap button.

The head isn’t spectacular, but I do like the functional aspect of the built-in wrought iron hanger. The nut is fabricated of a brass bolt cut to length and filed down to half its diameter. I left the head on, because the bass string pulls with greater force than its counterpart. The knurled nuts are my personal favorite; if I could, I would find a place for them in every project—they just look so cool and sometimes offer excellent function.

The pickup is my own Junk Shop Audio Nd144 style, great for 1-string to 3-string applications. It has a compact design and can be installed in a number of creative ways—in some cases it can even be hidden completely for a smooth, uncut top appearance, to better preserve original cigar box artwork.

The strap nut is created from a bolt, a beveled washer, a 1/4″ aluminum sleeve, and a couple of nuts. However, its more important function is to attach the metal strip that holds the pickup in place. The strap is made completely from red and black duct tape; I feel it complements the instrument well.

Thanks,

Quick and Dirty Acoustic Pickup

Posted on February 18, 2017 by junkshopaudio

I needed a pickup that I could easily install and remove from guitar to guitar—this is what I created with few spare parts I had laying around.

I grabbed a Lego crate and lid got the housing and a RCA jack for the connection. The active agent is a piezo disk that I broke out of a buzzer housing.

Drilled a hole in the bottom of the crate and installed the RCA jack.

Then, I drilled a hole in the lid and inserted the piezo wires.

Next, I soldered the wires to the hot and ground terminals on the RCA jack and closed the crate.

To allow for easy installation and removal, I added a 3/8″ removable Glue Dot to the back of the piezo disk and one side of the Lego Crate. Done.

It needs some more sound shaping, but it has potential and is decent in a pinch.

Check out my video:

Thanks,

Yard Dog Tremolo (controlled by cellphone app)

Posted on February 17, 2017 by junkshopaudio

So…this is the newest addition to my Yard Dog collection—super low rent manifestations of repurpose and modification. This project is based upon the mechanism present in the Strobe Light Tremolo; however, instead of utilizing an internal light source, the light comes from a free and ordinary cell phone app. This allows for many variations, as flashlight apps with strobe light features can vary in speed and brightness, thus allowing for a bit of customization from user to user.

I started with an ordinary sardine can—cleaned it out and drilled the holes for two ¼” jacks and a single pole, double throw switch.

It’s wired simply—audio in to switch with one side as a bypass and the other side controlled by the photocell. The photocell was extracted from an ordinary nightlight that comes on automatically when a room becomes dark.

I originally had just the piece of painter’s tape over the top, but found that the phone created noticeable interference. Therefore, I lined the inside with aluminum foil and then carefully insolated the bottom with part of a sticky note and the top with more painter’s tape, just in case the foil shakes loose. Since the phone creates so much interference and it sits on top of the unit, I cut about an 1/8” of aluminum foil to keep my signal quiet; it is barely audible when the light turns on and off. I cut a small, strategic hole exactly where the phone’s LED light exits the phone.

Duct tape was the lowest rent covering that I could thinking of, so I placed two pieces over the top and ran my thumb around the edge a few times. Then, I used a razor blade to cut the excess tape close to the outer edge. I found the hole and cut the duct tape and then wrote the name in red Sharpe.

That’s it—a simple, effective analog effect driven by digital technology.

Watch my video:

Classical Acoustic Resonator Guitar

Posted on February 13, 2017 by junkshopaudio

I picked up this broken Fender Classical Guitar at a local antique mall for pretty cheap. The bridge was completely ripped off and tied to the headstock in a sandwich bag. I wasn’t sure what I was going to do with it, but thought, why not.

First, I tried to clean the broken wood off of the bridge and guitar top; I applied glue and clamped it—that proved unsuccessful, so I cut a big ol’ hole in the top about the size of a stove drip pan, because that’s what I do.

I found that a paint can lid from a five gallon paint can fits perfectly over a stove drip pan—who knew. Four small screws were installed to keep the lid from shifting when the strings exert pressure. A tailpiece from an old acoustic was sanded and then added for greater stability.

I cut the ends off of the bridge to make in more compact and then cut and stacked two pieces of brass rod to serve as a saddle.

I found that this modification required a lot of reinforcement—I glued the bridge to the lid, cut small holes on either side, and then zip-tied a similar-sized block of wood to the bottom of the paint can lid from over the bridge. Additionally, I installed a brass bolt through the top of the lid that secured it to the drip pan via an old mounting bracket from a junction box.

I strung it with nylon strings just to see what it would sound like—it doesn’t resonate similar to steel rather, the resonating sound comes from the unplayed/untouched open strings and the untouched top. The player must keep his or her arm off of the top of the guitar or it will sound like any other classical guitar, which is cool, because it offers flexibility with regard to sound.

That’s it; check out the video:

Stay tuned for the removable pickup rig that I have designed for use with this guitar, since nylon strings negate use of my 9 volt power adapter pickup.

Thanks,

Yard Dog – Aluminum Level Full-Scale Steel Guitar

Posted on January 26, 2017 by junkshopaudio

I saw this level at the antique mall about a year ago and immediately knew I wanted to make a guitar out of it, but I wasn’t sure how. I originally wanted to keep the components within the confines of the level, meaning that the outer border of the level would remain untouched, but that kept me inactive for months. It would also have deprived me of full-scale 24.75″ fret spacing, which is my usual preference. A couple of weeks ago, I discovered a configuration that would allow me to have full-scale and correctly position the pickup.

So…parts wise, I used an well worn level that I believe was used in conjunction with pouring concrete, since I spent a lot of time chiseling chunks of cement out its small nooks and crannies.

For the pickup, I used my usual power adapter style; however, the string action was too low to allow me to install it on the top side of the level, so I had to install from the bottom and then build the magnets on the top side. The rusty razor blades look cool, but they also serve as a steel foundation for the magnets. The homemade nature of the pickup adds to the rustic/primitive charm of any build.

The jack assembly was constructed from a square erector set plate and an RCA jack. A standard 9-hole square plate was cut, bent to a right angle, and bolted to the level. The angle end was drilled and a single RCA jack was installed. RCA jacks are not often used for guitars, but some builds have space issues—this build was such that a 1/4 inch jack would not easily install within the required parameters. RCA jacks can be adapted to 1/4 inch via specialized adapters and cords at any point within the signal flow.

The tuners are ground-down thumb screws and rod nuts. This is a simple machine that I have used on two other projects that had very specific space limitations, which otherwise could not have been accommodated with standard precision tuners. These tuners are very precise and hold their tune, but the turn ratio is quick so tuning must be changed in small increments. Much like the pickup, fabricating the tuners from simple parts adds to the DIY/homemade quality.

The nut and bridge are made from cut prices of rebar and the strings are fastened to the frame at the end opposite the tuners with bolts and nuts. The strings go on easy and a hex driver is used to tune with precision.

The strap is made from 41″ hook bungee. I cut the hooks off, drilled holes in the plastic ends of the bungee and each end of the level, and then attached it with zip-ties. It’s easily removed—just cut the ties and then zip-tie it back on when desired.

Another quick and dirty for your listening pleasure:

All in all this four-string steel guitar turned out pretty decent, though it could benefit from higher action for better playability. I recently entered it in a local build contest at the St. Louis MO Cigar Box Guitar Club and won a Boss RC-50 Loop Station that was formerly owned by cigar box guitar virtuoso Justin Johnson-very cool.

Bennet and I pictured here with the steel guitar and loop station:

Here, Justin Johnson fires up a 3-stringed shovel guitar:
http://www.youtube.com/watch?v=V9-ltPsbw9g&list=RDEMh1KAwCgn9B_YzEmSF_RBFg

Thanks,

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Category Archives: Uncategorized

Better Bolt Bridges – Left-handed Thread Rod

PVC Bamboom Stick

Bennet’s Bamboom Stick

Shakespeare Hardback Book – Three-Stringed Electric “Cigar Box” Guitar

Cecil Whittaker’s Pizza Box Guitar

Fireplace Pan Electric Guitar

Quick and Dirty Acoustic Pickup

Yard Dog Tremolo (controlled by cellphone app)

Classical Acoustic Resonator Guitar

Yard Dog – Aluminum Level Full-Scale Steel Guitar