Identifying and Dating Kay Guitars (2024)

Identifying Kay Guitars

Unlike modern manufacturers like Fender, Taylor, and Martin,

The Kay Musical Instrument Company did not publish their internal serial number system and thus most Kay instruments cannot be pinned down to an exact date of manufacture.

This is my best attempt at pooling information together to help people identify their instruments

I cite my information as best as I can but there are points that are common knowledge among the Kay 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, feel free to Contact Meand I will do my best

Branding

Its a safe bet to say that a decent chunk of Kay-built instruments do not say Kay anywhere on them which has led to decades of confusion which I hope to untangle.

A significant portion of Kay's business was producing and selling instruments to retailers who would then sell them as their own house brand of instruments. There are a variety of names that Kay guitars appeared under from Airline to Marathon to Silvertone to Windsor! And yet there are plenty of Kay guitars that left the factory without a single marking at all.

Here is a complete guide of all the brand names I have encountered and who built for them

Company History

1890

The Andrew Groehsl Companywas formed in Chicago and began production of guitars, mandolins, and traditional European instruments

1921

Groehsl is bought out by Henry "Kay" Kuhrmeyer, Frank C. Voisinet, and Charles G. Stromberg and thus formed Stromberg-Voisinet. [7]

1931

June, Kay Kraft line is announced to be shown at the S-V booth at NAMM [9]
July 1st, The Kay Musical Instrument Company is formed [8]

1938 [9]

62 employees were involved in the production of instruments
Instruments were sold through 40 wholesalers in 15 states on top of mail order
The total sales of the company amounted to around $250,000
60 percent of all finished instruments were sold outside of Illinois

1965

Kay purchases Barth-Feinberg, a large music retailer in New York [13]
The Kay Musical Instrument Company is purchased by the Seeburg Corporation, a jukebox manufacturer [12]

1967

Kay was purchased from Seeburg by Valco [11]

Japanese-imports led to decreasing profits and Seeburg's desire to get out [14]

1968

Valco goes out of business

1973

The "Kay" brand is revived and applied on Japanese-import musical instruments

Headstock Shapes and Logos

February 2024, after Michael Wright threatened legal action against me for referencing his book and including a picture of 3 lines of text, I will no longer recommend his book. His complete lack of understanding in how Fair Use works, my lack of funds to defend myself from his litigation, and his attitude towards a fellow appreciator of Kay guitars have resulted in my complete loss of respect for the man. His book will no longer be referenced or recommended on my website

If you want to find his book, you'll have to do it the old fashioned way but realize that he saw this website and decided I needed to be put down.

Image of a 1930s chopped flat headstock used on certain Kay models has been removed

after threat of legal action by VintAxe.com who claim to be the copyright holder to the referenced 1930 catalog. It'll be public domain after a few years

Quintessential Kay shape
[1941-1968]

Image Credit: Reverb - BirdHouseMusic
Large 3-point
[1948-1958]

Gibson-esque "open book"
[1938-1944]

Harmony-esque 'rounded'
[1938-1947]
Three-line 'a' logo
[1940s]

Stamps

Kay instruments had a variety of ink stamps, most of which have meanings that have long since been lost. You can find the stamps on the inside of the back of the instrument which is usually visible with a flashlight via the f-holes or sound hole. It is a consensus of the Kay community that Kay instruments do not have a serial number system and that most of the stamps are likely related to the batch of instruments that it came from. It is also not unusual for a Kay guitar to not have any stamps or markings at all
It is certainly possible that the workers at Kay knew how to interpret these stamps and maybe even track down a date in case of a quality control issue.Any such knowledge has been lost and never surfaced.Coincidences where the stamps appear to refer to the year have happened but they are infrequent enough to just be happenstance.
"L#### ####" or "L####"
The "lot" number of the instrument which refers to which batch of instruments it came from
It does not containanyinformation about the year that the instrument was made.
Rarely, the second set of numbers is the model number but I've only seen it on the K-6100 and K-6000 models
L590 6889in a K-6970 Swingmaster
L4229 6100in a K-6100 Western Dreadnought
I've only ever seen the numbers match on the K-6000 and K-6100 models
"K-#### ####"
Numbers immediately following the "K" are the model number of the instrument
Any additional numbers have no known meaning and are presumed to be a batch number

K68 is the model number of this mandolin
468 is a batch number
"N#", "P#", "B#"
No known meaning
Commonly (and incorrectly) attributed to be a model number
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
P4 stamp

N-2 stamp
"DEC ####"
Only appears on some instruments built in the 1930s and 1940s
"DEC" would logically refer to December but I have not found any stamps referencing any other month so I'm unsure
"####" or "##" refers to the year the instrument was built
"DEC 1938" with what looks like a "2" written after it
"DEC 1941"
(the year is stamped upside down)
"???? 45"
"SECOND"
Appears on instruments from the 60s with obvious blemishes such as a knot in the wood (as was the case with this instrument)
Image Credit: Ebay
"K##" stamped on the back of the headstock
Only appears on instruments built in the 1930s and very early 40s.
"##" refers to the model number of the instrument.

Tuning Machines

Kay guitars used tuning machines from a few suppliers during their lifetime. Waverly tuners are able to be dated within decade ranges while Kluson tuners can typically be dated more exactly and are the best method of putting a year behind your guitar. I've attached an external resource which I frequently use and two articles that I have written about these tuning machines below.

Waverly

"Square" and "Small Bell" end plates used in the 1930s and into the 40s
"Bell" end plates used intermittently on student level instruments in the late-50s and 60s

Kluson

Appeared as early as the late-1930s and continued until Kay's demise
Often removed, sold separately, and replaced with cheap tuners
Unique "scalloped" plate end design is easily identifiable
Appears on most instruments prior to the 1960s
Remains on mid and higher tier instruments

Misc Japanese

Took over on student model instruments in the 1960s

Identifying Kluson closed-back(1947-1969)tuners:http://www.guitarhq.com/kluson.html

Identifying Kluson open-backtuners (1930s-1947):https://www.stlamateurluthier.com/2019/08/guide-to-kluson-open-back-tuners.html

Identifying Waverly tuners:https://www.stlamateurluthier.com/2020/02/waverly-musical-products-company.html

Kluson tuners are currently being produced by WDMusic and their reproductions can be pretty close to the originals. The best method of confirming originality is to look at the washers on the ends of the tuner shaft. Original, vintage tuners will have

metal

washers while reissues will have

nylon

washers

Nylon tuner washers indicating reissue tuners placed on a '60s Kay

Bodies

Kay guitars have a reputation for using laminated woods (as opposed to Harmony's reputation for solid wood) and their instruments were advertised in catalogs as "crack proof". However, this is not a strict rule and finding a Kay built with some solid wood is not nearly as uncommon as people think.

You can identify a solid or laminated top by checking any unbound edges to see if the wood grain is consistent or by using a mirror and a flashlight to do spot checks on the grain from the outside and inside of the instrument. If an instrument has cracks in the wood that run with the grain then that piece of wood is solid.

Spruce tops

Solid tops are prevalent on flat top guitars until the 1960s when it becomes hit or miss
Pre-1960s archtops are likely to have solid tops
Thinline/hollowbody instruments have laminated tops
Most, 50s-60s, student model instruments have laminated tops

Birch tops

Appear on student grade instruments like archtops and flat tops
Often laminated

Mahogany back and sides

Laminated more often than not

Maple back and sides

Highly figured pieces are often laminated
Solid sides and back do exist but they are typically not as figured

Birch back and sides

Often laminated

Brazilian Rosewood

I do not know whether the Kay Kraft Model C has solid or laminate
The K-6000, most famously used by Elmore James, has laminate back and sides

Solid body instruments are typically constructed of multiple pieces of poplar and can feature a maple veneer on the front and the back.

Carved vs Pressed

Carved top instruments have their tops built from a large solid block of spruce and are shaped to the desired profile. Pressed tops are either solid or laminated wood of a 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.

These are fairly uncommon but some of the high end models from the 30s and 40s may have them

Carved tops disappear entirely by the mid 1950s.

Necks

Kay necks were 'guaranteed' against warping by the inclusion of steel rods (some adjustable) in the neck. The name "Speed Demon" originated from the name of the neck profile on some of the 50s guitars but was later applied to the K57x line of instruments [5].

Poplar is the most common wood used for Kay necks

Often finished in a brown lacquer to mimic mahogany

Maple

Plain maple can be seen on some pre-1960 mid tier instruments
Figured maple can be seen in multi-piece necks on high end instruments

Mahogany

Appeared as late as the 1950s on high end instruments
Much less common than the previous woods

Fretboard

Wood analysis comes from personal experience andwww.wood-database.com's article on identifying Brazilian

Brazilian Rosewood

Standard for most 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]
Very sweet smelling when sanded
Reddish brown to jet black color (some cheap cuts can be pretty light colored)

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, orchemically ebonized

Chemically ebonized boards appear in the 1930s on instruments such as the Kay Kraft line

Can also be left natural with lacquer or dyed red

Walnut

Used in the 1940s and sometimes lacquered over

Position markers

Pre-1950s position markers are often true pearl while later ones are often celluloid. I've seen true pearl on a 1966-68 flat top and have seen celluloid on a 40s archtop so it isn't a solid rule.

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

Pick shaped inlays

Appeared on mid to late 60s guitars

Some painted inlays can be found like the K1160 "music note" guitar.

Frets

Composition

Standard nickel frets are the most common
Brass frets appeared in the 1950s and continued until the company's demise.

Typically reserved for lower end instruments

Zero-Fret

Zero frets onlyappear on Kay guitars made after 1968
1968-1970 - Valco-designed instruments
Post-1970 - Japanese-import instruments that use the Kay name

Size

Thin, short frets were common before and during WWII
Later guitars either had a standard size or a jumbo size which was wider
I cover a variety of exact fretwire dimensions on my articleVintage Fretwire Dimensions

Truss Rods and Neck Reinforcements

Kay guitars did not advertise neck reinforcements until the 1950s and from experience I have found that most instruments built before then relied solely on the strength of the wood. Kay used either a non-adjustable neck reinforcement or a true truss rod, never both.

Neck Reinforcements

Pre-1940s - None
1950s-1959 - U-shaped steel bar, open-end facing downwards
1960s - Rectangular steel bar

Truss Rods

"Thin Lite" which was introduced in the early 60s and is most similar to a Gibson style rod. Appears on mid-tier instruments.

The design is a long carriage bolt between two half-moon washers. It is held in place by the square hole in one washer.
These often become dislodged and are rendered inoperable but they can often be "repaired" by pulling the truss rod (by the nut) away from the body perpendicular to the strings and slowly turning until the end of the rod locks back into the washer.

Kay truss rod illustrating the design and the flaw that plagues them

"Kantilever" or "Balanced Tension" which was introduced in the 1950s and is adjustable at the heel of the instrument. Appears on higher end instruments like the Thin Twin and some of the fancier archtops

These are terrible and don't work well at all

Image Credit:https://www.banjohangout.org/archive/331297

Image Credit:1959 Catalog

Neck Joints

The Zorzi adjustable neck joint was invented by Joseph Zorzi who was hired at Stromberg-Voisenet in either 1926 or 1927 [6]. It first appeared in 1932 with the line of Kay Kraft instruments that it is best associated with. But you can also find them on other 30s lines like the Kay Deluxe. It was intended to prevent against costly neck reset operations by allowing the user to easily adjust the angle of the neck to the body.

The Zorzi neck joint disappeared, along with the Kay Kraft line, at the end of the 1930s.

'Zorzi' adjustable neck joint on a 1930s Kay Deluxe

The joint featured a radiused, dyed wood block with a raised center rail that was secured to the body of the instrument with three small nails. The neck was carved to mate with the block and had a groove which could slide along the rail. A bolt protruding from the neck fits through a hole drilled in the neck block and is secured with a wing nut. That bolt is held in place by a wood screw driven through the heel of the instrument.

Instruction Sticker
Image Credit: Facebook - Thom R

The mounting hardware that appears on the Zorzi neck

Dovetail

The most common and traditional neck joint for guitars and stringed instruments. Kay cut big, sloppy dovetails and relied on the glue to hold them in place which is why tons of Kay instruments have necks pulling away from the body

Bolt On

1961 was a transitional year for Kay when instruments started switching from dovetails to a 3 bolt system. It is prominent in electric hollow-body instruments and student model acoustics. The nicer acoustics typically kept their dovetail joints.

1960s 3 screw neck joint

1968 saw the introduction of a micro-tilt adjustment in the new Valco-designed instruments.

3 screw neck with microtilt

Bridges

Pyramid bridges appeared on some instruments in the 1930s through the 1940s. Bridges from this era also have two pearl dots hiding bolts that mount the bridge to the top.

Brass decorative carriage bolts are a staple of Kay flat top bridges from the late 1940s until the end of the 1960s. They typically have brass nuts which are tightened from underneath to secure the bridge to the guitar top.

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

Labels

Early Kay builds featured foil labels which were adhered to the back of the instrument and are visible through either the soundhole or the bass f-hole. These often fall off and are lost but can be very helpful when they are still intact.

Light Blue/Silver Label (1930s)

"Manufactured by Kay Musical Instrument Co Chicago"

Dark Blue/Red Label (1940s)

"Worlds Largest Manufacturers of String Instruments"
"Kay Musical Instrument Co"
"Chicago Established 1890"

Pickups

Kay guitars did notuse Gibson or DeArmond pickups like people on the internet often claim. The design and materials of Kay pickups are unique compared to original pickups from both of those manufacturers and so I believe it is more likely that Kay wound them in-house using their own employees.

I've put together a guide of all the Kay electric pickups I've found and the date ranges that they appear.

Kay Guitar Pickup Encyclopedia

$$$ Value $$$

The big question everybody asks is "How much is my Kay guitar worth?" and that is a fantastic question! It depends heavily on condition and playability since every Kay guitar is at least 50 years old and needs a good amount of work to get it back into playable shape.
The value of your instrument is directly related to the amount of work it needs.

I often see people selling their Kay instruments for $300 as "wall hangers" or "slide guitars" which is a nice thought but ultimately like selling a wrecked automobile for $10,000 as a "lawn ornament".
People won't pay top market value for a project instrument.

Reverb.com is one of the greatest resources for finding what your guitar really sells for, I would highly recommend checking there and clicking the "Show Sold Listings" checkbox in the filter. Find out what your instrument actually sells for, subtract the cost of repairs, and you should land around a fair price for your instrument.

Feel free toContact Me and I can provide information about your guitar's model and age

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 nottry to fill the cracks with glue or put clamps on the guitar to press it together
Your guitar needs proper humidityand cleats

The neck heel is pulling away from the body

Do notshove glue in there, you won't do anything except make a later repair harder
Some folks put a screw through the heel to hold it in place. I don't like that method but oh well
Your guitar needs a neck resetor a proper bolt-on conversion

The frets have large divots in them

Frets are like tires on your car, they need replacing every so often
Your guitar needs a refret

The strings are buzzy or the neck is bowed

Most Kay guitars lack adjustable truss rods and so forward bow cannot be easily repaired.
Your guitar needs a fretboard planing and refretor 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.
Some people will recommend shaving down the guitar bridge which is like putting a bandaid on a broken bone and damages the original bridge beyond repair.
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 notuse glue to fill the gaps or drive screws into the bridge to bring it back down. The only fix is to remove the bridge, lightly scrape off any lacquer, sand the bridge bottom to match the contour of the top, 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

Tone capacitors are often the first to go and replacing them is not unheard of
Pots can be cleaned with DeOxit

Your guitar needs an electronics evaluation and cleaning

Research

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

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

Kay Vintage Reissue - 1953
Kay Vintage Reissue - 1954
Kay Vintage Reissue - 1956
Kay Vintage Reissue - 1959
Kay Vintage Reissue - 1960
Kay Vintage Reissue - 1961
Kay Vintage Reissue - 1962
Kay Vintage Reissue - 1966
Kay Vintage Reissue - 1968

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

Kay Vintage Reissue - Models and Dates by Michael Wright

Sources

[1]https://www.wood-database.com/wood-articles/distinguishing-brazilian-rosewood-from-east-indian-and-other-rosewoods/

[2]https://reverb.com/item/16020800-silvertone-p7-archtop-jazzbox-from-the-early-1960s
[3]https://reverb.com/item/1282372-kay-n-15-1950s-1960s-sunburst
[4]https://reverb.com/item/25986397-kay-b10-1960s-brown-sunburst
[5]https://www.stlamateurluthier.com/2018/10/vintage-guitar-neck-reinforcements.html
[6]https://books.google.com/books?id=msEJ8cMqng4C&pg=RA3-PA1930&lpg=RA3-PA1930&dq=michael+wright+zorzi&source=bl&ots=zaFbs_y2Mb&sig=ACfU3U2pdN-kFRLq74hk89XZhkHqW9HMqQ&hl=en&sa=X&ved=2ahUKEwj8konkppXoAhVGaq0KHUGHCX4Q6AEwAHoECAUQAQ#v=onepage&q=michael%20wright%20zorzi&f=false

[7] https://mtr.arcade-museum.com/MTR-1922-74-10/31/

[8]https://mtr.arcade-museum.com/MTR-1931-90-7/34/

[9]https://www.nlrb.gov/case/00-R-000474

[10] https://mtr.arcade-museum.com/MTR-1931-90-6/17/

[11]https://www.google.com/books/edition/The_Purchaser_s_Guide_to_the_Music_Indus/GsIgAQAAIAAJ?hl=en&gbpv=1&bsq=kay+valco&dq=kay+valco&printsec=frontcover

[12]https://books.google.com/books?id=ISkEAAAAMBAJ&pg=PA55&dq=kay+seeburg&hl=en&sa=X&ved=2ahUKEwjI-Omr-8r1AhUwHjQIHZRLCgsQ6AF6BAgHEAI#v=onepage&q=kay%20seeburg&f=false

[13]https://www.google.com/books/edition/The_Purchaser_s_Guide_to_the_Music_Indus/AY85AAAAMAAJ?hl=en&gbpv=1&bsq=barth-feinberg+kay&dq=barth-feinberg+kay&printsec=frontcover

[14]https://books.google.com/books?id=CCkEAAAAMBAJ&pg=PA84&dq=kay+seeburg&hl=en&sa=X&ved=2ahUKEwjI-Omr-8r1AhUwHjQIHZRLCgsQ6AF6BAgGEAI#v=onepage&q=kay%20seeburg&f=false