The Amateur Luthier

Cataloging my experiences and encounters repairing and restoring guitars

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  Measuring a mandolin top in thousandths of an inch Image Credit: Popular Mechanics Vol 42 c.1924 In the above illustration, a man can be s...

 

Measuring a mandolin top in thousandths of an inch
Image Credit: Popular Mechanics Vol 42 c.1924

In the above illustration, a man can be seen using a deep measuring gauge to ensure that a given mandolin top fits the desired specifications. The factory or make for these instruments are unknown 

Repairing a mandolin brace
Image Credit: Popular Mechanics Vol 35 c.1921

This is a reader submitted article on how to repair a broken brace on a bowlback mandolin using common materials

 "Mike" Guitar Pickups There are a variety of guitar pickups that have the word "Mike" in them (referencing the word mic...

 "Mike" Guitar Pickups

There are a variety of guitar pickups that have the word "Mike" in them (referencing the word microphone) so I'm putting together this resource to help document some of the existing pickups I have found.

There does exist a DeArmond FHC "Guitar Mike" pickup but that is unrelated to these pickups and so I won't discuss it.

Melody Mike 


  • Manufacturer: Unknown
  • Date of Production: Unknown
I acquired this pickup installed on a 1950s Kay flat top guitar that was set up to play Hawaiian style music and was immediately curious. I contacted a very reputable DeArmond collector at https://www.musicpickups.com and he told me that this unit did not appear to be from DeArmond-Rowe. Later as I started working with more real DeArmonds I realized that the units are, in fact, totally different

The pickup was an unpotted single coil pickup with a plastic bobbin and brown cellophane tape protecting the bobbin. The black plastic cover was glued on and has "Melody Mike" engraved very lightly into it. It mounts with two tabs and a spring steel tensioner that bears against the bottom of the guitar soundboard. The control unit was a single volume with a Dakaware knob and a CTS pot that was soldered to the baseplate so the date code was obscured. The control unit has brown felt to prevent marring on the instrument.

Unique and Interesting Early Guitar Patents There is no particular rhyme or reason to these, they are just patents I found interesting among...

Unique and Interesting Early Guitar Patents


1898

 

1912

Alois Streicher Mandolin Tuning Machines 1900s Alois Streicher mandolin tuning machines About I found this set on an old maple/mahogany bowl...

Alois Streicher Mandolin Tuning Machines

1900s Alois Streicher mandolin tuning machines

About

I found this set on an old maple/mahogany bowl-back mandolin that had been heavily oversprayed and damaged. The tuning machines are in remarkable shape for their age and are almost entirely free of corrosion. The only identifying stamp on the tuning machines is PAT. OCT. 22 '95 which would refer to October 22nd of 1895. Bowl-back mandolins haven't been mass produced in America for a hundred years so 1995 was out of the question. 

I am not as knowledgeable on pre-1930s tuning machines as I would like to be. These stood out as being uniquely constructed compared to any other tuner I had seen prior and I was curious to see who made them. The fleur-de-lis shape on the end of the plates and the solid brass construction helped distinguish these tuners. Maybe this could help out someone else

Finding the Patent Number With Only the Issue Date

If you have used the search engine of the United States Patent and Trademark Office (USPTO), you'll know that you can only search patents filed prior to 1975 by the Patent Number, Classification, or Issue Date. These patents have been photographed (probably by some poor interns) but not truly "digitized" so you cannot search them for phrases or keywords.

I first conducted an Issue Date search for 10-22-1895 and found nearly 500 patents. The USPTO website isn't the most friendly for doing repetitive tasks quickly so I wasn't about to search them all. I then explored the Patent Classification route but was unable to determine which classifications existed at the time. The current "musical instrument" classifications did not exist then.

So I turned to one of my main resources for research, Google Books. The have a huge repository of digitized literature that is searchable by text and has been incredibly helpful in my work.

Annual Report of Patents 

I searched "october 20 1895 patent" and the first result was Annual Report of the Commissioner of Patents for the Year 1895. This book contains all of the patents filed in 1895 and would contain the information I desired. I then searched the book for the term "musical instrument" and page 596 contained two dozen entries for musical instruments. I walked down the Issue Date column until I found "Oct. 22" and before me was the row for Patent 548,475, filed by A. Streicher, described as "musical-instrument string-peg device".

Excerpt from the Annual Report for 1895
[Source]

Alois Streicher's Tuning Machines

Aloysius (Alois) Streicher, the inventor, filed the patent as the assignor to the The John Church Company of Cincinnati, Ohio. Alois was born in 1851, immigrated to the United States in either 1868 or 1871, was a "model maker" in the year 1900 and was listed as a "manufacturer" of "instruments" in the 1910 census. He died in December of that year. His son, also named Alois, was listed as a toolmaker in the 1900 census [2]. 

Patent Images from USPTO [1]



The worm gear brackets are actually stamped out of the base plate via die punches and are then bent at a right angle. The base plate is brass but the patent mentions a copper alloy as being an option as well. The gears are brass with slotted, steel screws fastening them to the post. The screws stick slightly proud of the gear which is curious but not a negative. The buttons are faux-ivory and melted on. They are secured by the peened end of the shaft which is very common from this era.

Backside of the machines showing the die punched plate

Sources

[1] https://pdfpiw.uspto.gov/.piw?docid=00548475&SectionNum=3&IDKey=D031DE1EEBCC&HomeUrl=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2%2526Sect2=HITOFF%2526p=1%2526u=%25252Fnetahtml%25252FPTO%25252Fsearch-bool.html%2526r=1%2526f=G%2526l=50%2526co1=AND%2526d=PALL%2526s1=0548475.PN.%2526OS=PN/0548475%2526RS=PN/0548475
[2] https://www.familysearch.org/ark:/61903/3:1:S3HY-DKY3-M8C?i=7&cc=1325221&personaUrl=%2Fark%3A%2F61903%2F1%3A1%3AMM8W-83Q

Harmony and Japanese Parlor Guitars These instruments are similar to each other and can be difficult to distinguish between 1960s Harmony H-...

Harmony and Japanese Parlor Guitars

These instruments are similar to each other and can be difficult to distinguish between

1960s Harmony H-150

Image Credit: Reverb - BW Guitars


Japanese-made

Image Credit: Pinterest - Ebay


1960s Harmony H-929
"Stella"

Image Credit: Shop Goodwill

Japanese-made

Image Credit: Reverb - Evolution Music

1960s Harmony H-929

Image Credit: Reverb - Mun Dane Guitar Lode

Japanese Guitar

Image Credit: ShopGoodwill







I just purchased 14 clamps from a resident in St Charles, MO that came from her great grandfather who apparently built furniture. She didn&#...


I just purchased 14 clamps from a resident in St Charles, MO that came from her great grandfather who apparently built furniture. She didn't have any more information on them except that I purchased 14 of them and a few went to another family member. 

 Most of the screw clamps are from the R. Bliss Mfg Co, one from the Dodge Mfg Co, and the rest are stamped "GAR No.6" which I've been unable to decipher. According to clamp enthusiast websites on, these were built in the latter half of the 1800s. They're all in surprisingly good condition and work pretty well minus the need for some lubrication and well deserved cleaning.

All of the clamps are stamped with "Seidel" or "Seidel & Winkler"


Seidel & Winkler


1887 Seidel & Winkler Advertisement [1]

Google's archive of digitized and searchable books was the best method to finding out where these clamps came from. I found about a dozen documents that mentioned the business name at least in passing, most were directories, but one had an old advertisement which I've included above. The earliest reference to the business I can find is from 1866 and the latest was from 1889. I discovered both their full names in Volume 8 of Gould's St Louis Directory; Ernst L. Seidel and Frederick A. Winkler who were both carpenters [2]. 

According to the above 1887 advertisement from a book entitled "The Industries of Saint Louis" by John W. Leonard, Seidel & Winkler built fixtures for businesses. The ad explicitly mentions railings, mantels, shelving, and mirrors. Their office was located at 517 Locust St, an area which has been redeveloped multiple times and currently is a parking garage, and their factory at the southeast corner of Linn and Soulard St [1]. Another document placed their factory on the 1700 block of Linn Street [2].

1903 Rand McNally and Company Map
Image Source: David Rumsey Map Collection

Linn Street no longer exists but "The Revised Ordinance City of St. Louis" from 1893 sheds some light on where it would've been. It ran North to South and was bordered at the north by Park Avenue and at the south by Geyer Avenue. Based on my amateur detective work piecing together old maps, I figure it would be situated at present day South 14th Street [4][5]. The area has been redeveloped extensively and is currently a residential neighborhood. 

Later

In 1954, the Seidel Furniture Company was established in St Louis with the Seidel Coal & Coke Company having 100% interest in the business. They were located at 3524 Washington Blvd in St Louis. It is unclear when the company ceased to exist but I presume they were from the same family as the earlier Seidel's. [3]

Sources

[5] http://maps.slpl.org/img/mom00161.jpg


About Celluloid originally referred to products made from cellulose nitrate but now is used to refer to similar, more stable chemical compos...

About

Celluloid originally referred to products made from cellulose nitrate but now is used to refer to similar, more stable chemical compositions of plastics. It was one of the first industrial thermoplastics and revolutionized the world when it became widely produced. Originally designed to provide a cheaper alternative to ivory but later was used for film and a variety of purposes including imitating other expensive materials. It eventually fell out of favor due to its extreme flammability and dimensional instability which caused it to shrink and distort with age. It still remains a staple of the guitar world due to its widespread usage in vintage instruments and the community's desire to use and repair with authentic materials.

Tortoise shell imitations were one of the more common materials used in old instruments for pickguards and appointments and they varied wildly in design and color. Many modern tortoise shell imitations are simply printed designs on opaque or transparent plastic which is often unsatisfactory for restoration work and can look cheap. Proper imitation tortoise where colors are added to a transparent sheet can still be purchased and can even be purchased in cellulose nitrate but they can cost more and cellulose nitrate usually requires a hazmat fee to ship.

The art of making quality imitation tortoise was likely passed from worker to worker in these factories and has likely been lost to the ages but people have relearned the process and continue to make pretty darn good replicas. The purpose of this research is to document the historical processes that were used and what chemicals were involved. 

The Process


[1]
The first method comes from a 1907 book by Friedrich Böckmann entitled "Celluloid" which discussed the process of creating, working, coloring, and uses for the material. It is the book to read if you are interested in making celluloid but I highly recommend not doing so unless you have a concrete bunker far away from anything valuable. Most of the celluloid factories have burned down, if that's any indication. I've included an excerpt which discusses the process of creating imitation tortoise shell with celluloid. 

They first produce a sheet of clear, polished celluloid and dye it yellow with a solution of picric acid and a aniline brown. The exact parts unknowns. Then red spots are added via another solution of aniline brown and fuschin dye.

[3]
A 1904 book entitled "Cellulose, Cellulose Products, and Artificial Rubber" by Josef Bersch described a very similar process and describes the use of a paintbrush with the aniline brown and fuschin dye solution to add the spots.
[2]
An article written for "Textile Colorist and Converter Vol. 44" entitled "The Dyeing of Celluloid" by J. F. Springer in 1922 describes the process as well. The spots in the celluloid are colored via "various Sudan Browns and Reds" dyes. Another process involves using laminating sheets of colored celluloid and passing them through a heated press which, likely paired with an alcohol solution, bonds them together. This would create celluloid tortoise which likely has a more three dimensional and layered appearance compared to dying a clear sheet.

Finally the article mentions the "very best of all methods" which involves hand coloring individual sheets which results in a product that is "almost impossible to distinguish" from the real thing. It doesn't elaborate any further.

[4]

An excerpt from "Workshop Receipts: For Manufacturers and Scientific Amateurs, Volume 4" written in 1917 describes the celluloid imitation tortoiseshell. It first involves taking celluloid in a paste medium and mixing a part with brown aniline dye, mixing another part with yellow dye, and kneading them into a part of clear celluloid. 


Sources

[1] Celluloid by Friedrich Böckmann: https://books.google.com/books?id=2ok6AAAAMAAJ
[2] Textile Colorist and Converter Vol. 44: https://books.google.com/books?id=5qs7AQAAMAAJ
[3] Cellulose, Cellulose Products, and Artificial Rubber by Josef Bersch: https://books.google.com/books?id=pe5QAAAAYAAJ
[4] Workshop Receipts: For Manufacturers and Scientific Amateurs, Volume 4: https://books.google.com/books?id=cs9MAAAAYAAJ


History Fender doesn't have the same legacy in acoustic guitars as they do in the world of electric guitars and so their early acoustic ...

History
Fender doesn't have the same legacy in acoustic guitars as they do in the world of electric guitars and so their early acoustic instruments are often forgotten. You could buy a cheap acoustic from Fender as far back as as the 1950s but it wouldn't be until the early 60s that you could buy an acoustic that was built in the Fender factory. These were not well received at the time but aren't terrible instruments and those models inspired Fender's current line-up of acoustic instruments. .

To preface, the first Fender-built acoustics were introduced in 1963 and featured bolt-on necks (often with Stratocaster headstocks) paired with bodies that had an aluminum rod running parallel to the strings connecting the neck and tail blocks. On their official website, Fender has an article called Beaches, Stages and the Silver Screen: A History of Fender Acoustic Guitars which covers these models. These guitars are most closely related to what Fender is producing today and many of the model names were recycled. But fans of the Tim Armstrong "Hellcat" guitar might notice an unusual shift in design and that is because Fender did not build the instrument that it was based on.

For background, the Harmony Company was based in Chicago, Illinois and was one of the world's largest producers of musical instruments until it's dissolution in 1975. A significant portion of Harmony's business was through selling their instruments to distributors who would resell them and allow for smaller stores to tap into the growing musical instrument market. Many Harmony instruments don't even have the Harmony name on them as they were often built and sold unbranded or custom ordered with a company's chosen brand name painted onto the instrument.

Fender first sold unbranded Harmony instruments in the late 1950s and in the late 1960s commissioned Harmony to build a line of Fender-branded acoustics that blended the styles of the Fender-built acoustics and the regular Harmony lineup. To the best of my knowledge, these instruments were only offered between 1969 and 1971 before Fender shifted to Asian-import acoustics in 1972.

The purpose of this article is to document these Harmony-built instruments and provide a cross reference for model numbers.

Fender F-1000 / No.150 (1956-1959, 1969-1971)
aka Harmony "Stella" H-929 or Harmony H-150
Image Credit: Reverb - Two Losers Vintage


First appearing in the late 1950s as the No.150 "Student Spanish Guitar", the Fender F-1000 was the cheapest acoustic you could buy from Fender and one of the cheapest from Harmony. In the early days, it appeared at the end of the Fender catalogs like a footnote and did not bear the Fender name. Later it received its own Fender model number and finally had the Fender name on it's headstock.

It is based off two Harmony models; the H-929 Stella and the H-150 (which was likely it's early namesake). The headstock profile is identical to both models but it blends design features from both with pearloid dots in a dyed fretboard, large two-tone sunburst, trapeze tailpiece, and a modified pickguard.
  • Neck: Poplar
  • Fretboard: Ebonized Maple
  • Top: Solid Birch
  • Back and Sides: Solid Birch
  • Binding: Painted
Fender F-1010 (1969-1971)
aka Harmony "Stella" H-949

Image Credit: Reverb - Galloway Originals

    The Fender F-1212 is a rebranded Harmony H-949 which was their budget version of their popular Harmony H-162. It has the Fender designed headstock, custom rosette, custom pickguard, and Fender styled bridge. 
    • Neck: Poplar
    • Fretboard: Ebonized Maple
    • Top: Solid Birch
    • Back and Sides: Solid Birch
    • Binding: Painted
    Fender F-1030 (1969-1971)
    aka Harmony H-165 Folk

    The Fender F-1030 is most closely related to the Harmony H-165 all mahogany folk guitar. It has a unique Fender headstock shape, pickguard (pictured model lacks it), and bridge. It has a larger, painted rosette than the H-165 typically has. This model was the originator of the Tim Armstrong "Hellcat".
    • Neck: Mahogany
    • Fretboard: Indian Rosewood
    • Top: Solid Mahogany
    • Back and Sides: Solid Mahogany
    • Binding: None
    Fender F-1050 (1969-1971)
    aka Harmony H-1203 Sovereign
    Image Credit: Myself

    The Fender F-1050 is a rebranded version of the Harmony H-1203 Sovereign acoustic guitar with a unique Fender headstock shape, pickguard, and bridge. 
    • Neck: Mahogany
    • Fretboard: Bound Indian Rosewood
    • Top: Solid Spruce
    • Back and Sides: Solid Mahogany
    • Binding: Black and White Celluloid
    Fender F-1060 (1969-1971)
    aka Harmony H-1260 Sovereign Jumbo
    Image Credit: Reverb - Spacetone Music

    The Fender F-1060 is based on the H-1260 Sovereign Jumbo which is an incredibly popular model even today. It is a jumbo dreadnought instrument. It has a Fender headstock with an inlaid tortoise celluloid veneer, custom pickguard, and custom bridge.
    • Neck: Mahogany
    • Fretboard: Bound Indian Rosewood
    • Top: Solid Spruce
    • Back and Sides: Solid Mahogany
    • Binding: Black and White Celluloid
    Fender F-1070 (1969-1971)
    aka Harmony H-1270 Jumbo

    Image Credit: Reverb - Michael's Gear Emporium


    The Fender F-1070 is essentially a Harmony H-1270 jumbo 12 string guitar. It has a Fender headstock with an inlaid tortoise celluloid veneer, custom pickguard, and custom bridge.
    • Neck: Mahogany
    • Fretboard: Bound Indian Rosewood
    • Top: Solid Spruce
    • Back and Sides: Solid Mahogany
    • Binding: Black and White Celluloid

    Value
    The extremely helpful website GuitarHQ.com has documented many of the Fender-built instruments and has assigned them all a collectibility rating of an "F". I believe that rating doesn't accurately reflect the market value of these instruments on their own and is skewed because of the comparisons to the value of similar Fender products from that era.

    As the market shifts and values change, always consult Reverb.com's "Sold Listings" to see what people are actually buying them for. At the time of this article's writing, this is what they are going for.

    The Fender-built acoustics vary but I've seen them go from $500 to $2000 depending on the model and with earlier models or rare colors selling for more. The King and Kingman are the most desirable.

    The Harmony-built acoustics tend to stick pretty close to their Harmony-branded counterparts but it isn't unheard of for them to bring a little bit more money from people just wanting a vintage Fender-branded acoustic. They can go from $150 up to $800 depending on model and condition. 

    Robert Lehrmann Sales Agent  3125 S. Jefferson Ave. St. Louis, Mo. Label from a '20s Gibson L-1 About Robert Ervin Lehrmann was born in ...


    Robert Lehrmann Sales Agent 
    3125 S. Jefferson Ave. St. Louis, Mo.
    Label from a '20s Gibson L-1
    About
    Robert Ervin Lehrmann was born in 1879 in Germany to Amelia and (father's name unknown) Lerhmann. They immigrated in 1890 to the United States. In the 1900 census, Robert's occupation was listed as an "actor" and in 1910, he was listed as a manager of a stationery business [1][2]. He married a Missouri woman named Hilda sometime in the teens and by the 1920 census was teaching music out of his house [3]. The 1920 census lists his birthplace as Ohio which I believe to be in error. The census records for 1930 are unavailable but in 1940 he was a banjo player in an orchestra [4]. He had no children and died in 1948. According to the University of Illinois archives from the Hunleth Music Company collection, Lehrmann was the director of the Gibson School of Music (1889-1937) [5]. 

    Robert acted as a salesman for Gibson during the 1920's and many of the Gibson instruments from that era around St Louis feature his label. The label is typically placed atop the factory labels and often partially obscures them. The building on the label was demolished at some point and is currently an empty lot

    Sources

    St Louis Music Supply was founded by the Kornblum brothers in the early 20th century and they distributed a variety of instruments from d...

    St Louis Music Supply was founded by the Kornblum brothers in the early 20th century and they distributed a variety of instruments from different manufacturers. My interest in them comes from my location (just outside of St Louis) and that I've already acquired four guitars that were sold by them, one for each decade between the 1930s and 1960s. 

    I've been searching for a couple years for St Louis Music Supply catalogs and found these pictures but have yet to find any that I could purchase, scan, upload for others, and use as reference material to figure out the years and dates behind my instruments. St Louis Music Supply used the Custom Kraft brand name primarily and that is my focus.

    If you have found one, please shoot me a message

    Guyatone and Zen-On Plastic Guitar Bridges Teisco has nothing to do with these but people often incorrectly  refer to any  vintage Japa...

    Guyatone and Zen-On Plastic Guitar Bridges

    Teisco has nothing to do with these but people often incorrectly refer to any 
    vintage Japanese guitar as being made by "Teisco" so its worth mentioning

    About

    A weird chapter in the totally bizarre world of 1960s Japanese-built electric guitars is the molded plastic bridge which appeared on instruments by two distinct manufacturers. Both bridges are molded from an off-white plastic and do remain fairly sturdy; I haven't had any issues with them crumbling or chipping. Tonally, I haven't A-B'd them against a traditional metal bridge but all 3 instruments I've had with these bridges sounded a little more 'thumpy' than I expected.

    You can find these on Ebay and Reverb for about $30-40. It wouldn't be a bad move to start reproducing them but that's beyond my capabilities

    Guyatone

    Guyatone produced electric guitars for major guitar manufacturer Suzuki. The company also produced their house brand Guyatone. Badged guitars produced by Guyatone include Barclay, Broadway, Coronado, Crestwood, Futurama, Howard, Ibanez, Ideal, Imperial, Johnny Guitar, Kent, Kingston, Lafayette, Marco Polo (electrics only), Montclair, Omega, Orpheus, Prestige, Royalist, Saturn, Silhouette, Silvertone, Vernon, Winston and Zenta, an impressive amount of names produced by a single company. [1]
    Guyatone plastic bridges can be easily identified by their softer angles and compensation. They are also less wide than the Zen-On bridges.


    I've also found this variant on a Guyatone guitar which is uncompensated but has similar dimensions. I presume its an earlier design

    Zen-On

    Little known Japanese manufacturer who was out of business by 1968. Zen-On made electric guitars with the house brand Zen-on badge, as well as Beltone, Morales and Zenon badges [1]
    Zen-On plastic bridges are distinguishable due to the sharp angles and drastic compensation for the strings. They are also wider than the Guyatone counterparts.



    Sources

    About I was unable to source any information about the company  Employees Bertha "Bertte" Sofo, was a secretary with the ...

    About

    I was unable to source any information about the company 

    Employees

    Bertha "Bertte" Sofo, was a secretary with the company in 1940 [1]. A public notice of a marriage between her and  businessman William Hauser, in 1946, listed her as an "exec" at the company [2].

    Sources

    [1] https://www.familysearch.org/ark:/61903/3:1:3QS7-89MB-PPRP?i=3&personaUrl=%2Fark%3A%2F61903%2F1%3A1%3AKW1X-1MQ

    An original flier from a 1950s Kay Archtop with the Kanti-Lever truss rod system I went ahead and transcribed the letter for your rea...

    An original flier from a 1950s Kay Archtop with the Kanti-Lever truss rod system

    I went ahead and transcribed the letter for your reading pleasure.

    HOW TO USE YOUR "KANTI LEVER" ADJUSTABLE GUITAR NECK
    Your new guitar is equipped with a balanced tension neck. The purpose of this adjustable feature is to enable you to keep your guitar neck in perfect alignment at all times.

    Having been made very thin to permit fast, tricky progressions, the wooden neck is subject to atmospheric conditions. These atmospheric conditions, plus the tension of the strings, tend to warp or bent the necks. In addition, the alignment of the neck is affected by a change in pitch, change of strings, and a change of bridge height. You can now keep your neck in perfect alignment with Kay's ingenious "Kanti Lever" reinforcement inside the neck. Built around the lever principle, with a specially alloyed steel truss rod and a positive screw adjustment, this neck is now virtually fool-proof.

    Your guitar neck was perfectly aligned when it left the factory. Should any further adjustment be needed, you can do it yourself with the handy "T" wrench that was included. Insert the wrench in the hole in the heel of the neck (where the neck joins the body) turn the key to the right (clockwise) to adjust the neck back; turn the key to the left (counter-clockwise) to bring the neck forward. Ordinarily, a turn or less will put your instrument back in perfect alignment. Do not readjust the neck unless it proves necessary. Be sure your guitar is in tune before readjusting the neck.

    Dating Harmony Guitars Harmony guitars are fairly easy to identify and date yet there still remains a lot of unsolved questions for the ...

    Dating Harmony Guitars

    Harmony guitars are fairly easy to identify and date yet there still remains a lot of unsolved questions for the average collector which I am attempting to answer here.

    The single best resource on the internet is the DeMont Harmony Database but it is no longer updated.
    I am attempting to bridge the gap where he stopped and with what we know today.

    I cite my information as best as I can but there are points that are common knowledge among the Harmony community or are observations and conclusions that I have reached from my work.
    Pictures are mine unless otherwise cited.

    If you are unable to identify your instrument, use the Contact Me button above and I'll do my best.

      Branding

      Harmony instruments have their name on them more often than Kay instruments do but there is still a significant number of these instruments which do not sport the name of the manufacturer. Many Harmony instruments have a brand name which was given by a retailer who purchased the instrument for sale as a house brand in their own shop. You can find Harmony guitars branded Airline to Heathkit to Wizard and more!

      I have compiled guides on identifying these instruments and who sold them.

      My original article (which includes pictures) of the various brand names that Harmony guitars appeared under can be found here:
      Harmony Guitar Brands and Aliases (not updated)

      My current list (which does not have pictures but is updated) has even more brand names that Harmony guitars appeared under.
      Department Store Guitar Brand List

      Headstock Variants

      Quintessential Harmony headstock shape
      [1936-19??]
      Slender-waist
      [1930s]

      Thin, small nub
      [1940s]
      Kay-esque single point
      [Late 1960s-1970s]



      Tuning Machines

      Harmony guitars primarily used Waverly tuning machines on their models throughout the lifetime of the company. Kluson tuners started appearing in the 1940s.

      My guide to identifying Kluson tuners can be found here
      My guide to identifying Waverly tuners can be found here

      Bodies

      Harmony acoustic instruments are praised for their use of solid woods. They require more care than laminate guitars (to prevent cracking) but provide better tone.

      Carved vs Pressed

      Most Harmony archtop guitars have heat pressed tops which are formed in molds to make the archtop shape which produces a good sound but is nowhere near as desirable as a true carved top. 

      There do exist models where the bracing is carved out of the same piece of wood as the top.

      Necks 

      • Poplar is the most common wood used 
        • Often finished in a brown lacquer to mimic mahogany
      • Mahogany 
        • Appears on higher end flat top models like the Sovereign series 
        • Also appears on mid to high end archtops as early as the 1940s. 

      Neck Reinforcements

      Double bar reinforcement slots on a 30s archtop
      • Pre-1940s - Single or double rectangular steel bar
      • 1940s - Often none
      • 1950s-1970s - Single rectangular steel bar

      Truss Rods

      Harmony unveiled the Torque-Lok dual-rod truss rod system in 1956 which was paired with their Slim-Line neck for 'professional' and 'fast' playing.

      Unfortunately the design has flaws. As tension is added to the rod, the nut is forced downwards into the channel but the upward pressure which makes adjustment difficult. The rod also stops short of spanning the full length of the neck which reduces its, already weak, effectiveness.
      1950s Harmony "Torque-Lok" Truss Rod
      Partially removed for demonstration


      Fretboard

      • Brazilian Rosewood
        • Continued to appear on mid to high-end models far into the 1960s
      • Ebonized hardwood (maple, birch, etc)
        • (Read my Article here about the process)
        • Very common on low-end models throughout Harmony's history
        • Ebonizing process causes the wood to 'dry rot' which reduces its strength and leaves it brittle and prone to cracks and chips.
        • Very unpleasant to refret. 
      • Indian Rosewood
        • Started appearing in the 1960s as a cheaper alternative to Brazilian
        • More porous and differently colored than Brazilian Rosewood 

      Position dots

      Inlay materials are typically real pearl up until the 50s when celluloid "pearloid" becomes commonplace.
        • 3/16" white dots in an alternating 1 and 2 dot pattern appeared in the 1930s
          • Kay also used this pattern and dot size
        • Ornate stenciled designs can also be found
          • Painted on, typically, with white lacquer

      Frets

      • Composition
        • Standard nickel frets are the most common
        • Brass frets appeared in the 1940s
      • Size
        • Thin, short frets were common before and during WWII
        • I cover a variety of exact fretwire dimensions on my article Vintage Fretwire Dimensions

      Stamps

      Harmony guitars are, in most cases, very easy to identify via their comprehensive stamping and dating system. Ink stamps are typically found on the back of the instrument and are visible through the f holes or soundhole. It is not uncommon for the stamps to be poorly inked, faded, or obscured.

      Harmony date stamps variants
      Image Credit: UNKNOWN
      Please contact me if you made this so I can applaud you
      • "F-##", "S-##"
        • Means Fall or Spring which refers to the season in which the instrument was built
          • It does not mean First or Second half of the year
          • The existence of "FL" date stamps and of Christmas-exclusive models bearing "F" stamps (for Fall) supports this conclusion
        • "##" refers to the year in which the instrument was built
        • If followed by a letter or letters, that indicates the inspector of the instrument that approved it. 
      Harmony H-54 built in the Fall of 1951
      "3585" has no known meaning and can be ignored
      Image Credit: Ebay
      • "####H####"
        • Preceding numbers are likely a batch number and have no discernible meaning
        • Following numbers are the model number of the instrument and can be easily researched on such websites as the DeMont Harmony Database
          • Harmony was known to reuse model numbers
      • "Carved Top"
        • Often printed in red ink, indicates a high end model with a carved arch top
      1938 Carved Top Stamp
      Image Credit: Reverb - Tommy
      • Dovetail Stamps
        • Sometimes the dovetails will have stamps on the heel that can only be seen during a neck reset
        • Possibly another method of dating the instrument? I'll have to find more examples
      4847 stamp on dovetail on a 1948 archtop
      • Miscellaneous Stamps 
        • "PVC"
          • Unknown meaning, possibly referred to the binding material?
      From a 1940s "Gene Autry"
        • "UV-S2S"
          • Unknown meaning
      From a 1940s Harmony Monterey


      Labels

      Harmony guitars typically don't have any paper labels glued inside them from the factory. Most paper labels are from the distributor like B&J which had their own serial and model number labels. Starting in the 1960s, select models had labels which were visible through the soundhole or f-holes.

      • "A Quality instrument handcrafted by The Harmony Company"
        • Appears on 70s Harmony guitars, a few USA but mostly Korean built
      • "Special Notice This guitar is designed for nylon or gut strings do not use steel strings"
        • Appears on 60s-70s classical guitars warning players not to use regular acoustic strings

      Pickups

      Harmony purchased their pickups from outside suppliers and, to my knowledge, did not wind their own.

      DeArmond-Rowe

      Harmony pickups were built primarily by DeArmond-Rowe Industries which constructed the famous "hershey bar" and "gold foil" pickups (not to be confused with later Japanese gold foil pickups). If your Harmony has electronics, chances are that they are DeArmond. DeArmond also assembled the wiring harnesses for pickguards that used their pickups

      Luckily, DeArmond units are well documented and typically have a date stamp on the back of the instrument in Month Day Year format like MAR 18 1966. This will align very closely with the date of construction of your instrument. The best resource for DeArmond pickups is https://www.musicpickups.com/

      Gibson

      Gibson P-13 pickups are often referred to as the precursor to the famous P-90 pickup and were built in the 1940s and 1950s. There is a rumor that Gibson sold Harmony a "boxcar" of pickups and Harmony used that stock until they ran out. Nobody knows the specifics but we do know for sure that Harmony used Gibson pickups (and Gibson lap steel wiring harnesses) in some of their instruments.

      1950s Gibson P-13 Pickup (no polepieces) on an H-56 Roy Smeck

      Do not confuse these pickups with Speed Bump pickups from Kay or pickups from Alamo. Too many people falsely attribute these pickups to each other but they are not associated in any way except appearance

      Common Issues 

      DIY repairs are the quickest way to damage and devalue an instrument
      Always consult with a reputable luthier (not a guitar tech) before performing any work
      Never ever use super glue, epoxy, gorilla glue, or Titebond III
      Guitars that are 'repaired' with these are often beyond saving
      • There are cracks in the wood
        • This occurs when an instrument is exposed to a climate different than the ideal (70 degrees Fahrenheit and 45-50% humidity) and the wood has shrunk
        • Do not try to fill the cracks with glue or put clamps on the guitar to press it together
        • Your guitar needs proper humidity and cleats
      • The neck heel is pulling away from the body
        • Do not shove glue in there or drive a screw through the heel
        • Your guitar needs a neck reset 
      • The frets have large divots in them
        • Frets are like tires on your car, they need replacing after being used a lot
        • Your guitar needs a refret
      • The strings are buzzy or the neck is bowed
        • Most Harmony guitars lack adjustable truss rods (or rods that still work) and so forward bow cannot be easily repaired.
        • Your guitar needs a fretboard planing and refret or more ideally a truss rod installation
      • The strings are too high off the fretboard
        • As string tension and climate shift the wood in a guitar, they inevitably need the neck to be steamed off and a new angle carved relative to the body.
        • Your guitar needs a neck reset
      • The bridge is lifting and coming off
        • Many bridges are glued directly onto the lacquer which causes them to lift and raise the action. 
        • Do not use glue to fill the gaps or drive screws into the bridge to bring it back down. The only fix is to remove the bridge, prep the area, sand the bridge to match, and reglue it.
        • Your guitar needs a bridge reglue and often a bridge plate patch
      • There is no sound coming from the electronics
        • This can be a variety of things from dead capacitors, dirty potentiometers, shorted wires, and even dead pickups.
        • Don't replace any vintage components unless you absolutely have to
        • Your guitar needs an electronics evaluation and cleaning