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This focuses on Kay-built instruments from the 1930s through the late 1960s. All pictures are mine unless otherwise cited. Design  B...

Identifying and Dating Kay Guitars

This focuses on Kay-built instruments from the 1930s through the late 1960s.
All pictures are mine unless otherwise cited.



Not all Kay instruments had a big "Kay" on their headstock, many times they were built without a brand for distributors. I do not know at what point in the manufacturing process the brand was added but I have seen Kay instruments without a trace of a badge or logo. Frequently these instruments were bought by companies like retail stores who were looking to sell their "own" brand of guitars and so Kay guitars are seen with a variety of names from Airline to Marathon to Windsor! 

Check my article about the different names that Kay instruments can be found under.

Headstock Shapes

Michael Wright has compiled one of the largest picture galleries of headstock photos in his book "Guitar Stories Vol. 2: The Histories of Cool Guitars". I own the book and have found it to be an invaluable resource in identifying these old guitars. You can buy the book on Amazon here

Here is an excerpt from his book. 

Quintessential Kay shape
Gibson-esque "open book"
Harmony-esque 'rounded'
3 point 


60s Narrow 

'T' shape logo

Plectrum shape logo

Tuning Machines

Kay guitars can be found with tuners built by Kluson Manufacturing Company. Kluson tuners can generally be identified by their distinctive plate shape which comes to two points with a dip in the center. Sometimes referred to as having a "scalloped" plate.

The absolute best guide for identifying 1947-1960s Kluson closed-back tuners is GuitarHQ

Kluson tuners with and without the 2nd tuner
post hole
Summarized dates from Guitar HQ 
  • Without 2nd tuner post hole.
    • Single Line ~ 1947-1952
    • No Line ~ 1952-1953
  • With 2nd tuner post hole
    • No Line ~ 1953-1956
    • Single Line ~ 1956-1958
    • Double Line ~ 1964-1969
Open-back Kluson tuners are typically pre 1950, rarely have identifying stamps, and must be identified by the style and what is known about the instrument they are on. Kluson tuners are reproduced by WDMusic and so the best way to confirm that they are vintage is to look at the washers under the end of the tuner shaft. Originals will be metal and reissues will be nylon or a white plastic.

Nylon tuner washers indicating reissue tuners

1930s Kluson single, open-back, stamped shaft with border 

1940s Kluson plate, open-back, stamped shaft
Late 1940s Kluson single, open back,
'waffle' stamped shaft
Late 1940s Kluson plate, open-back,
removable stamped shafts
1940s Kluson plate, open-back, screw shaft
Late 1940s Kluson 'single-line' tuners
wihout second tuner hole

1960s Kluson 'double-line' tuners


Kay acoustic guitars are known for their laminated woods (as opposed to Harmony's reputation for solid wood) and were advertised as "crack proof". Solid woods on Kay guitars are possible but most often appear as a solid Spruce top. Back and sides are very rarely solid. The best way to identify whether your guitar is solid or laminate is to have a mirror and a flashlight and inspect the wood to see if the grain is identical from the outside and inside. The top can be checked for laminations by the end grain visible in the soundhole.
  • Solid body
    • 3-piece hardwood construction with maple cap on front and back
    • Plywood started picking up in the late 60s
  • Acoustic
    • Spruce tops are solid until the late 1960s where it becomes hit or miss
    • Birch or maple tops are often laminated
    • Backs and sides are laminated more often than not
      • Mahogany is a common wood to find
      • Figured maple veneer 

Carved vs Pressed

Carved top instruments have their tops built from a large solid block of spruce and are shaped to the ideal profile. Pressed tops are either solid or laminated wood of the final thickness and pressed to their shape via heated molds. Carving a top is much more labor and time intensive than pressing so carved tops are typically reserved for the high end instruments and are less common than a pressed top. If you have a standard looking Kay archtop guitar, chances are the top was pressed and it is almost guaranteed with laminated tops.


Kay necks were 'guaranteed' against warping by the inclusion of steel rods (some adjustable) in the neck. Their truss rods were referred to as "thin lite" and their design most closely resembles the Gibson truss rods of the era [5]. These are prone to breaking at the welds.
  • Solid poplar with grafted headstock wings is the most common 
    • Often finished in a brown nitro lacquer to mimic mahogany
  • Maple on higher end models
  • True mahogany appeared as late as the 1940s

Neck Joints

1961 was the transitional year for Kay where instruments started switching from using dovetails to their 3 bolt system. This change did not affect all the instruments and many acoustics kept their dovetails (except the most inexpensive models). 1968 saw the introduction of a micro-tilt adjustment in the new Valco-designed instruments

1960s neck joint


Wood analysis comes from personal experience and's article on identifying Brazilian
  • Brazilian Rosewood
    • Standard for instruments up until the 1960s 
    • Started becoming reserved for only the high-end models
    • Tight, closed grain
    • Will not fluoresce under a blacklight when dissolved in water [1]
    • Reddish brown to jet black color
  • Indian Rosewood
    • Picked up in the 1960s as a budget alternative to Brazilian
    • Open grain. Twice the pores per square inch as Brazilian [1]
    • Dark brown or purplish brown color
  • Maple
    • Painted black, brown, or chemically ebonzied
    • Dyed red or lacquered natural on 1960s archtops

Position markers

    • Dots
      • 3/8" pearloid or white dots in a single line pattern appeared in the 1960s
      • 7/32" mother of pearl dots at latest in the 1950s
      • 3/16" white dots in an alternating 1 and 2 dot pattern were common prior to 1960
    • Blocks
      • Appeared on higher end instruments, celluloid.
    • Pick shaped inlays
      • Appeared on mid to late 60s guitars
    • Some painted inlays can be found like the K1160 "music note" guitar.


Brass decorative bolts are a staple of American-built Kay flat top bridges from the 1940s until the end of the 1960s. 
Kay bridge bolts
Flat top bridges can either be pinned or pinless and generally look similar to the picture below. Some Kay jumbo guitars have an adjustable saddle built into the bridge and a third decorative bolt

1960s flat top bridge
Standard on most all Kay flat tops

1940s archtop bridge
(with added B string compensation)
1960s hollow body bridge
(no B string compensation)


Kay guitars do not have traditional serial numbers that can be understood. They often have a variety of stamps that were used internally but any meaning has long since been lost. These body stamps will sometimes tell you the model number but yield no information on the date of production. 
  • "K-#### ####"
    • Stamped inside the body on the back
    • Numbers following the "K" are the model number of the instrument
    • Remaining 4 numbers are meaningless and likely batch related
  • "L#### ####"
    • Stamped inside the body on the back
    • Assumed to be related to the batch in which it was built
    • Commonly (and wrongly) attributed to be a model number
    • Has no discernible meaning towards the date of manufacture
  • "N#", "P#", "B#"
    • Stamped inside the body on the back
    • Unknown meanings 
    • N numbers can go up to 15. [3]
    • P numbers can go up to 7. [2]
    • B numbers can go up to 10. [4]
    • N and P numbers can occur together
    • B and N numbers can occur together


Check up my write up and pictures of the pickups used on Kay guitars. Also comes with helpful date ranges


The internet and the incredible effort by members of the community to digitize old catalogs make it quite possible to date instruments made by Kay between the 1950s and 1970s. Anything before 1950 gets a little trickier to date due to the lack of available catalogs and so

Once you have used the above information to get an approximation of how old your guitar is, I would recommend checking out these resources to try and narrow down the date of production.

Catalog Scans

Model Numbers and Production Dates

This excerpt is one of the most complete lists of Kay guitar model numbers and production dates from Michael Wright's book "Guitar Stories Vol. 2: The Histories of Cool Guitars". I intend on developing a Kay model database at some point



  1. Replies
    1. During the 70s, I'm not too familiar with the later import Kay guitars as I am with the American build instruments


Be excellent to each other dudes