The “Copy Carver”

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The Copy Carver is set up on two sawhorses. The carriage and table can be seperated and stored when not in use.

Today, I put my new Copy Carver into operation. The Copy Carver is the invention of Ed Walicki, a wood carver from Michigan, who developed it to easily duplicate three dimensional wood carvings and other sculptures. I made mine from his plans so that I can duplicate banjo necks, hollow out autoharp bodies, and custom manufacture large quantities of fine sawdust. To me, the Copy Carver represents an affordable, analog alternative to the CNC routers that are so popular nowadays. CNC, or Computer Numerical Controlled routers cost thousands of dollars and are just not right for a small shop such as mine. I like to think of my Copy Carver not as a CNC router but rather a P (pencil)NC router.

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The stylus is guided around the inside of the model/frame while the router begins to cut the autoharp body.

The Copy Carver has a work table upon which are clamped a model of the item to be duplicated and a rough blank to be carved. A rolling “swing box” holds a powered trim router and a stylus in precise alignment. The carriage rolling on the tracks guides one axis while the swing box can be guided up and down and back and forth on the other two axes. Carving involves guiding the stylus over the model while the router precisely cuts the blank.

I have been making very stable autoharp bodies by hollowing out 1-1/2″ laminated maple  such that the pinblocks, sides, and back are of one unit with no joints to fail. It’s a bit wasteful but I think much less so than a finished instrument that could fold, warp, or crack requiring future repair. To rout the bodies in the past I tried to control a router by hand and the process was positively frightening. Now, the Copy Carver allows me to safely complete the task with less effort.

DSC03760My initial (r)outing with this machine is a left-handed, or reverse, autoharp made to play on the lap without having to cross hands. I’m routing out the inside of 1-1/2″ laminated maple to a final depth of 1-1/4″. That will leave 1/4″ (or two plys) for the back. The model is just some scrapwood framed into the exact inside shape that I will cut into the autoharp body. Later, I can turn this same frame/model over to rout an autoharp body in the conventional, right-handed configuration. The work is as slow  as the old way but at least I’m confident that I will finish the task with all or most of my fingers and eyes.

DSC03759The Copy Carver’s swing box is counter balanced with 15 pounds of barbell plates and fine tuned with a few handy spring clamps so that guiding the stylus and router is almost effortless. A screen door handle grasped with the left hand makes it easier to roll the carriage on the tracks.DSC03757

Making a curved compensated banjo bridge, part two

 

images-1Compensated  bridges come in several forms but they all, as an integrated unit, vary the speaking length of the individual string courses to “compensate” for the effect of string mass on intonation. For years, until dedicated craftsmen developed alternatives, the “Grover” compensated bridges were all that seemed available.

 

DownloadedFileAt some point “Moon” style banjo bridges entered the scene offering arc shaped bridges of different sizes and weights. It’s this style of bridge that I’m going to make here.

 

Ordinarily, bridges like these are cut from a thicker piece of a hardwood such as maple and capped with ebony. Instead, I am going to laminate two strips of bubinga with a thin strip of ebony in the center. The grain of each strip will be arranged horizontally to resist the strings tendency to cut into the wood.

Each strip is around 1/10″ thick and 4″ long. In the final set-up, the bridge could be anywhere from 1/2″ to 5/8″ high so I make the strips 3/4″ high. Having that much extra material will allow me to reduce the height equally from the cap and the base to achieve the final height.

DSC03716I draw center lines both ways. The vertical line marks the position for the third string and the 5/16″ center hole. The horizontal line also centers the 5/16″ hole plus the two 3/8″ outside holes. I have marked the positions of the other four strings and located the two 3/8″ holes between the 1st and 2nd and the 4th and 5th strings. I won’t glue the pieces together yet. I’ll clamp them together to maintain alignment while I drill the three holes.

DSC03728In the past, I have used the “Grover” compensated bridges with some success. I have never liked the way they sound and couldn’t imagine the steps in making one like that, but the degree of compensation seems to work for me. Using one for reference, I found the arc of an 11″ diameter circle closely intersects each of the five points where the strings cross the Grover. I made a form for my laminated bridge by cutting that arc in a piece of scrapwood.

DSC03729The strips are springy enough that they won’t fracture when clamped into the gentle arc. I applied “gel” type CA glue to the strips, aligned the holes, and clamped them into the form. I chose to use CA over yellow wood glue because it is harder and denser for better sound transmission. I chose the “gel” because it allows a little longer “open time” for aligning everything.

 

DSC03730CA glue sets up fast when the “kicker” or accelerant is spritzed anywhere near the joint. When the clamps are removed, the bridge assumes the curve of the form without any spring back.

 

 

DSC03731From this point there are countless possibilities for shaping and thinning. I wish I had time to try them all. I bandsaw the rough shape and use my oscillating spindle sander for shaping and thinning. The holes can be enlarged and areas can be thinned to achieve a different , hopefully better tone.

This bridge will have a center foot to prevent sagging and keep the strings level. For the feet to have better contact with the head, the entire base will be sanded into a very subtle curve with the center foot being slightly lower than the outside feet.

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Making a curved compensated banjo bridge

A seemingly simple but very complex component of any banjo is the bridge. It transmits much of the vibrating string’s energy to the head, maintains precise string spacing and height, and determines each string’s vibrating length from the nut. All of these functions influence how well the banjo sounds and plays. Many factors determine how well the bridge functions. The species of wood (or inorganic material), grain and grain orientation, weight, shape and size, and geometry are only some of the details that make one bridge perform different from another.

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A “Grover” maple and ebony banjo bridge

Not long ago, the banjo player had few choices. Music stores would carry two or three footed “Grovers” that might or might not bear an ebony cap. The two standard heights, 1/2″ and maybe 5/8″, usually had to be sanded or filed for a good fit. To compensate for irregularities in intonaton these straight bridges were rotated a few degrees.

Nowdays, there is a whole industry of industrious industrialists crafting and testing hundreds of designs for sale to players pursuing that perfect tone. The player can buy and try (at $20 to $40 a go) bridges by the handful to swap back and forth, comparing volume, tone, and sustain. In forums, articles, and advertising, there is endless discussion about bridges made of exotic hardwoods, submerged logs, factory floors, and discarded pallets.  By searching  “banjo bridges” on Google images, one is presented with such an astonishing array of choices that it’s hard to know where to begin.

My most recent banjo build was an amplified five string with a 26-3/8″ scale that will be played bluegrass style, with picks. The customer does not capo for key changes but plays chords up into the high frets. I don’t have a lot of experience with this type of banjo nor did I have the opportunity to experiment since the instrument was shipped out of state. In setting out to make the bridge, my goal was to have something with a crisp tone, an adequate degree of compensation, and a hard cap that would resist string cutting. Additionally, I wanted a shape and style that could be easily thinned and tweaked for improved tone and sustain.

In the following post/s I will describe the steps in making this curved bridge of bubinga and ebony.DSC03731

 

Instrument building plans, some for free

Each time I begin a new project, I search the web for related information such as images, specifications, historical details, construction methods, and any ideas that I can  legally buy, borrow or steal to make my new favorite instrument a success. First to get “googled” are plans and blueprints. By purchasing blueprints or downloading free plans, I can have an informed starting point for my own unique designs which I then share with visitors to my site.

2014-06coverI have always found “Musicmakers” in Stillwater, Minnesota an excellent information resource for many of the instruments that interest me. They sell completed instruments, kits, parts, materials and blueprints for the beginning builder to the skillfull luthier. Their innovative designs produce good sounding instruments that are straightforward and easy to build.

Last week, I received their May 2014 catalog which offers free digital downloads of ten of their instrument plans. They also have for sale  hardware and string packages collated for each of their blueprints, both purchased and free.

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“Autochord”

Among the free plans are dulcimers, mandolins ,travel guitars, the “Autochord”( their version of an autoharp), and the “Suitcase Bass” (a unique upright bass that can be disassembled for travel). The plans that I have downloaded are in PDF format and include photographed construction procedures as well as blueprints. I haven’t tried these yet, but sometimes I can take downloaded files to “Staples” and have them printed on large paper at 100% scale for use as full size templates.

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“Suitcase Bass”

The free plans appear to be for instruments and kits that Musicmakers no longer make. Purchased plans are are available for most of the ones they still offer.

 

 

After a considerable absence

I truely love publishing my “What’s he building in there?” weblog and having contact with the like minded folks who read it. I have been absent since late last March and I am eager to resume posting about my lutherie and answering the varied inquiries and comments that I receive. I should probably explain…

DownloadedFile-3First, please ignore anyone who claims to have seen me by an Ohio roadside these past three months. That wasn’t me! The only thing in my wardrobe that remotely resembles an orange jumpsuit is the tangerine colored leisure suit and white “Crocs” that I only wore when Mrs. WHBIT and I married, and later to the many, many job interviews before I became happily self employed.

Truth be told, the main reason for my absence was a serious medical issue that hospitalized Mrs. WHBIT for two and a half weeks in March/April and the lengthly, tedious recovery that is still ongoing. We are very thankful that she feeling better and has returned to her work (and that I don’t have to dress for any job interviews). I am  now current with my routine piano work and instrument repairs and hope to post about new projects and ideas soon. Thank you for your patience.

 

 

How to replace a wound autoharp string with a guitar string

Caitie from Amsterdam contacted me recently regarding her old German zither that was missing a wound string. She wasn’t prepared to replace the entire set and was doubtful that sets are even available. Can the string be replaced with a suitable guitar string? How does one do that?

DSC03646Ideally, an ancient string set should be replaced but what if availibility or expense is a problem? What do you do when an autoharp string breaks the afternoon before the big gig? A guitar string of the correct size and construction can be a quick, temporary fix until a proper string can be found and installed.

 

Substituting a plain (not wound) string is easy. Determine the correct diameter and use the same size guitar string keeping in mind if it requires a loop end or a ball end. The thicker strings with windings around a core wire are more difficult because they must be modified so that no windings cross the bridges. This can be done by carefully unwinding portions of both ends so that only core crosses the bridges. Most guitar strings aren’t made to be unwound so in doing so, the remaining windings can become loose and noisy. Here, I’ll describe how I successfully unwind and secure guitar strings.

 

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The guitar strings winding is too thick to fit in the slot.

This Oscar Schmidt “B” model features bridge pins on the tuning pin end and a slotted comb on the tail end. It requires a ball end string but the thick windings at the ball are too thick to fit in the slot. I snip the ball and the thick bit off, unwind and expose enough core wire to twist around the ball, and continue to remove enough winding to clear the bridge when the string is seated in the slot (this hassle is mostly unnecessary for autoharps that use loop end strings).

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The ball is removed and the winding unraveled.

 

 

 

 

 

 

 

 

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A small finishing nail, inserted through the hole in the ball and clamped in a vise, makes it easier to hold the ball while twisting the core wire around it. Three or four turns will hold it and the ball can be twisted to tighten the loop. Leave a small tail on the core wire to prevent it from twisting loose.

 

 

 

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The core wire is twisted around the ball and enough winding is removed to clear the bridge.

 

 

 

 

 

 

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The end of the string is trimmed 2″ beyond the tuning pin.

 

The tuning pin has already been backed out three complete turns to accept the new string. With the prepared ball end seated in the slot, the other end is positioned around its bridge pin, pushed through the tuning pin hole, and held to hand tension. While holding everything in place, I snip the string off 2″ beyond the tuning pin and mark the winding 1-1/4″ below the bridge pin. The 2″ tail will allow three complete turns on the tuning pin and the mark is where the winding will end without crossing the bridge.

 

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The winding is marked 1-1/4″ below the bridge pin.

 

 

 

 

 

 

 

 

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Only the winding is cut, not the core wire.

 

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Only a slight tap is necessary to flatten the last few turns of the winding.

 

 

 

I lightly score the winding where I marked it being careful not to cut the core wire. The winding is unreveled to this point.

 

 

 

 

I “peen” the last few winding turns at each end to prevent the winding from becoming loose.

 

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With the new guitar string in tune, the windings stop short of the bridge pin. The new string will sound different than its mates but will fill the gap untill replacements arrive. Flattening the ends of the windings is usually successful but if they work loose, it sometimes helps to crimp them tighter with pliers or apply a small drop of CA glue to stop the buzz.

 

 

 

Continue reading

Spring done sprung

This winter has been a nightmare for all of us and it’s very frustrating to me that I haven’t had any workshop activity to report for several weeks. 2014 has seemed like years and years of cancelled appointments, clearing snow from the driveway, carrying cordwood, and engaging in my new hobby…emergency plumbing repair. Weeks of extremely low humidity have put everyone’s pianos out of tune, sent cracks racing through guitars and fiddles, and have exposed the sharp fret ends on my banjo, snagging my mittens when I play.

Yesterday, the afternoon developed into a soft, balmy, 63 degree respite, promising that Spring had arrived. We could finally open doors and windows (those that weren’t stuck) and emerge to the songs of the first robbins. I spent a few hours raking gravel, scraping layers of road salt from our vehicles, and tidying up the woodpile. It actually felt wonderful to perform these usually tedious tasks.

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Doh! Hardly ten hours later, it came back.

 

 

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There have been a few days when I could heat the shop and work on a Dulcijo for a player in Washington state. She sent me her unwanted, 8″ rim, Goldtone banjo for which I made and fitted a new maple and walnut Dulcijo neck. This custom neck features “Pegheds” tuners, a 1-1/2 fret, a 7th fret RR spike, and Nylgut strings.

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We can only hope that the winter’s relapse will be as temporary as the short respite. I’m already preparing materials for two new projects, a five string “steampunk” style banjo and an octave mandolin.

 

 

 

 

 

Three stringed banjos (dulcijos)

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The 10″ rim features a 25″ scale and a Fiberskyn head. The 8″ rim features a 24-1/4″ scale and a Renaissance head.

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The 10″ rim is tensioned with ten nickel plated brackets, the 8″ rim has eight.

My two new banjos are finished, tested, and for sale. They are prototypes built to a slightly different design so that they cost less than my custom dulcijos. By combining domestic hardwoods and conventional hardware, these instruments save about 30% over their costlier exotic wood and brass appointed siblings. They sound and play quite nice and even feature some added versatility.

 

 

 

 

 

 

 

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The three string bridges are 5/8″ high and made of hard maple, capped with ebony.

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The strings are anchored to a nickel plated “No Knot” tailpiece at the tail of the aluminum tension ring.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Both instruments have a “zero fret” as a termination point instead of a conventional nut. String spacing is maintained by a slotted plastic nut on one banjo and three brass escutcheon pins on the other.

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The escutcheon pins are effective and easy to install.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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A “scoop” is carved into the fingerboard, near the rim, and under the third string for playing “clawhammer” style.

 

 

 

 

 

 

 

 

Having three full length strings on this diatonic banjo adds an interesting bit of versatility. Tuned, for example, to the conventional mountain dulcimer configuration of DAD, it can be fretted, chorded, capoed, and strummed the same as a dulcimer. Building on that, It can be played in nearly any banjo style with the third (thumb string) open as a low drone, or hooked under the fourth fret “spike” as a high drone. I’m hoping that this style of dulcijo will appeal to the dulcimer player who wants an authentic banjo sound and to the banjo player who desires a fun, simpler, and less confusing ‘jo.

How do they sound? Words fail me every single time that I try to answer that question so I won’t even try. To me, much of the fun and challenge of building instruments is experimenting with varied materials and techniques just to see what I get. What I get with this new 10″ dulcijo with its Fiberskyn head and 25″ scale, is a sound very close to my custom dulcijos. Much of this is because of the relatively thicker Mylar and Tyvek laminated heads. The 8″ rim banjo is, of course, smaller and features a Renaissance head. The Renaissance head lacks the Tyvek layer and as a result seems (words, don’t fail me now!) brighter, louder, and has more sustain than the larger banjo.

 

 

Pete Seeger, 94

35329-13649142812014Pete Seeger has died at the age of 94. He has always been, and will always be, a hero and inspiration to me. Biographies and memorials aplenty about Pete’s music, politics, and social involvement can be found in the media this week. I can only offer some personal reminicinces that sadly, fall short in relating how much Pete means to me.

 

 

imagesPete’s book, “How To Play The 5-String Banjo” along with his involvement with “Sing Out!” magazine gave me my start playing, and later building, the five-string. His many books and albums sent the enthuiastic message that, you don’t have to be just a consumer/spectator of folk music, you can play and sing out too.

 

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How memorable to hear “Waist Deep In The Big Muddy”, “I Feel Like I’m Fixin’ To Die Rag”, “Cocaine Blues”, “Mr. Bojangles”, “Don’t Let Your Deal Go Down”, and other iconic folk songs of the time.

I actually had the memorable experience of singing with Pete (along with 8000 or so others) in 1971 when I hitchhiked with some friends to the Southern Ohio Folk Festival in Athens, Ohio. I can certainly vouch for all of the testimonies about Pete’s ability to have entire audiences on their feet singing one minute, and quietly meditating upon a serious social issue the next.

 

 

 

 

 

images-1When Mrs. WHBIT and I returned from overseas, more enthuiastic than ever about folk music, Pete was on our minds. He’s getting quite elderly (59), we reasoned, and we should hurry to see him while he’s still around. In the 1970s there was no internet or any easy means to find tour or concert information so we did things the old fashioned way and wrote Pete a letter. A few weeks later that same letter was returned to us. A rubber stamp imprint on the back said something to the effect that, “In order to conserve our precious natural resources, we are replying on your stationary”. Beneath that, was a handwritten reply from Pete’s manager, Harold Leventhal, describing Pete’s recent involvement with the sloop “Clearwater” and apologising that there were no concerts scheduled. The reply’s content was a disappointment but that simple rubber stamp imprint carried a message from the time when “Earth Day” and “Ecology” were still young, to the present. We consume too much. We must conserve every way we can.

 

 

Spike my ‘jo (part six)

DSC03601My two new dulcijos are built up, strung up, set up, tuned up, and are now learning to play nice. As with most siblings who share a large measure of DNA, they couldn’t be any more different and it’s no surprise. I’ll describe my impressions regarding sound and playability later, but first, some more about a new feature.

 

 

 

My custom dulcijos resemble conventional 5-stringed, open backed banjos  with the “thumb string” or high drone being tuned with a tuning peg installed part way up the neck. With three stringed dulcijos, this “thumb string” starts at the fourth fret. On these two new banjo/dulcimer hybrids however, all three strings stretch the entire scale length with all three tuners on the peg head. This permits the instrument to be tuned and played like a mountain dulcimer… quite fun for the dulcimer player who would like to apply his/her already killa skills to play banjo.

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A “spike” is installed under the third string and behind the fourth fret.

For me, the fun is playing dulcijo in the “clawhammer” style with its rhythmic high drone. I typically tune the three strings to dAa (d4-A3-a4) to play along with dulcimers that are tuned to DAd (D3-A3-d4). The full length third string (on the new dulcijos) would break if I tried tuning it to that high “a”, so I tune the third string to the same “d4″ as the first string and capo it at the fourth fret to produce the high “a4″ drone. To capo only the third string at the fourth fret I install a tiny hook called a “railroad spike” underneath the string.

 

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Tiny model railroad spikes

“Railroad spikes” have been used for many years to capo banjo thumb strings independently from the longer strings. They are actual railroad spikes in the sense that they are of a miniature scale used on model railroad tracks. I glue them into holes that I drill 3/8″ behind the fret and just under the string. Their tops are even in height with the frets and do not interfere with the string.

 

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When engaged, the spike seats the string on the fret to raise the pitch.

When needed, the string is hooked under the spike which seats it on the fret, raising the string to the desired pitch.

An added advantage in using this method is that it eliminates the tuning peg that would ordinarily protrude from the side of the neck. While the thumb string peg is part of the traditional character of the reentrant banjo, it sometimes gets in the way when fretting up the neck by obstructing the thumb.

 

Building the dulcijo with three full length strings adds a great deal of versatility. Held on the lap or upright, it can be tuned and played like a dulcimer. As a banjo, the thumb string can be tuned to a lower drone or seated under the spike for a high drone. With a combination of capoing and alternate tunings, these three stringed diatonic instruments can be played in an even greater variety of keys and modes.