Clock key size chart to get the right key
Clock key size chart explanation
Clock keys have there own number system from 000 to 16 as seen in the Clock key size chart. However the number does not indicate what size is what number and can be confusing. So how do you use the Clock key size chart to get the right key?
It would make more sense if the key size was the MM of how wide the key was to fit, but this is not how it works. This section is to figure out what key number to order so the clock can be wound up. Subsequently, the clock key gets lost the most out of any other clock part.
Of course, it can be tricky to find the right key for your clock because there are many sizes. The Clock key size chart will give us the right size key to order.
Double end clock keys
In addition, some keys have two sizes on one key and this is called a double end key. By and large, the clock key size chart will work for both the wind up part of the clock and also the smaller F / S portion. When the clock has a F / S regulator portion it will be at the 12 o'clock on the dial.
Alternately, if there is a small arbor inside of a hole at 12, this is the time regulator control and the key would have two ends. Thus, it may say F / S at this location or A / R. F / S stands for Fast or Slow, or it could say A / R to stand for Advance or Retard and is referring to the timing of the clock.
Of course, if the clock is running fast in time, turn more to the Slow or Retard direction to slow it down. Refer to the Clock key size chart with your measurements to find a key to work with this function.
Getting the right Clock key size
Given these points, to get the key needed, measure the shaft the key is to go on to, then use the Clock key size chart to get the key size needed.
Please do not call asking what key the clock needs, as you will be told it would still have to be measured. In short, measure the shaft that the key goes onto in MM and then use the clock key size chart to match it up.
The lazy way instead of the Clock key size chart
The Clock key size chart has all of the sizes listed however sometimes certain key sizes are known. Generally speaking, almost all post 1960 mechanical clocks, made in Germany take a size #8 key or crank, unless the movement is round.
Ordinarily the round ones take a number 4. The American time strike antique units mostly take the size 7 key. Match your measurements to the Clock key size chart to be sure.
- 1.75mm = 000 Key
- 2.0mm = 00 Key
- 2.25mm = 0 Key
- 2.5mm = 1 Key
- 2.75mm = 2 Key
- 3.0mm = 3 Key
- 3.25mm = 4 Key
- 3.5mm = 5 Key
- 3.75mm = 6 Key
- 4.0mm = 7 Key
- 4.25mm = 8 Key
- 4.5mm = 9 Key
- 4.75mm = 10 Key
- 5.00mm = 11 Key
- 5.25mm = 12 Key
- 5.5mm = 13 Key
- 5.75mm = 14 Key
- 6.0mm = 15 Key
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Attached is the clock from the previous message.
Usually size 7 for that one
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a 1920s Seth Thomas Cymbal #1 mantle clock. I need a new key. Measuring the shafts is difficult because they are somewhat recessed. Just eyeballing it with my dial caliper, 3.5mm looks too big. 3.25mm looks about right. Thoughts?
Usually size 7 for that one
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have an English Smiths railway/school clock that’s approx 43cm overall in diameter with the actual face being approximately 30cm. We’ve just moved and I can’t for the life of me find the key!!! Argggh! So, desperate as I am to hear it ticking in our new home, I’m reaching out to you. Would you happen to know what key it might take?
Many thanks in anticipation,
Adrian
Guessing size 8, Best to measure
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Great – thanks! Will give it a try!
I was gifted a Forestville 8 day mantel clock with chimes without the key. I took it to a local jewelry store who ordered some keys but none fit. How do I find the right key.?
Usually size 7 for that one
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
thank you! I’ll let you know.
What size key do I need? I have a Howard Miller, New Haven Wall, 620-196 with a Kieninger Clock Movement SPS-02 with Wesminster Chime – it has three key holes in the front of the clock face.Description of the movement is:
Kieninger Clock Movement SPS-02 is a 1/4 key wind movement with Westminster chime, run time 8 days, plate size 120 x 124 x 1,7 mm, spring driven, on 12-rod gong, pendulum version with Kieniramic7 solid anchor with stationary escapement (Graham) and automatic beat adjustment, cable/key wind movements with cable winding stops, chime shut-off, front winding.
Size 8 this link
https://www.clockworks.com/product/brass-single-end-clock-key
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Thank you so much! Have a great day!
Curious? Tera, is your last name Helser or Heiser? The name caught my eye – I am not aware of many of us Helsers. Sorry, not clock related. Initially looking for a clock key.
I have a 1970’s Howard Miller Jennison wall clock which says no 143 Triple chime key wind movement, model 612-432. Can you please tell me the ket size I need? It has been lost.
Size 8 for that one, this link
https://www.clockworks.com/product/brass-single-end-clock-key
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Thank you so much!
I have a grandmother clock marked The York County an original by Daneker Fallston, MD. It has three key holes on the face, but I have no keys and do not know if I need one or three or how to wind it. Can you help me? Thanks
Usually size 8
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Hello, I have a Hennegen Bates Co. mantel clock. Can you tell me what size key I need? Thank you.
Usually size 7 not always
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a Boodle and Dunthorne carriage clock.
What size key would I need please
Not sure on that one, best to measure
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have been given a National Time Recorders clock. Unfortunately it came without a key. Can you tell me what key I need for this clock?
Do not know that one
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Wonder if you could help identify key size for a J. Valery wall clock with alabaster face. The dial is 12″ in diameter.
Thanks
Not sure on that one, will need to measure and figure out how wide that winding arbor is in MM
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Good evening. I have a 1920s Sessions mantle clock and need a key. The shaft is behind the face, so I can’t measure the length. It also takes a key to adjust F/S, so I need a double ended key…thoughts? Thank you!
Size 7
Do not have the F/S end
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Hello,
I am searching for a brass replacement Cup that mounts on the base on my Std Kundo 400 day clock. Also, I’ve noticed that the brass is looking very poor on the Pendulum balls as well. If I can’t locate a source, is there a service that can re-brass these items?
Thanks for the assist James.
Never tried to do that. Not sure if it is even real brass. Maybe look into electroplating? These are not high value clocks.
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a lovely Eardley Norton London grandfather clock, but lost the winder key, can you tell me the replacement number?
Do not know that one from here
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Hi I have a seth thomas adamantine mantle clock with faux mantle. Please let me know the key size. Thank you.
Size 7
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Please could you let me know which size key I need for a 100 year old mantle napoleon
Thank you !!
Its 7 or 8, do not know what one from here.
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a HAC Chinoiserie grand-daughter clock, probably about 100 years old. When I purchased it there was no key but I was subsequently given one that fitted; however, that key was very old and it has now split so no longer works. Do you know what key size I should buy for the clock, please?
Do not, need to measure the width of the post and use the key chart
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a Seth Thomas schoolhouse wall clock. What size key do I need?
Usually size 7 if antique, if post 1950 usually size 8
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Antique German Urgos 1/2 & Hour Chiming Mantle Clock
Hello, I am looking for a key for this type of clock. I’m new to owning and any assistance would be greatly appreciated.
Thank you!
Size 8 key is needed for that one
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Antique Winterhalder & Hofmeier Cased ‘Westminster Chimes’ Mantel Clock c1890
I need a key for this. Currently there is one for sale on ebay virtually identical. Size is about 4.9 to 5mm but can’t be sure.
Please help
https://www.ebay.co.uk/itm/393781494346?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&customid=CjwKCAjwzuqgBhAcEiwAdj5dRmdcCnQFVS8ICiAD6qVWRGzskYMrCwuX4t9gfmokneTsemS5V2MRdRoCNNoQAvD_BwE
Usually size 8
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a French mantle clock, front escapement, with 2 holes on front – I have measured both arbors and it appears they are the same size however the front hole of one is smaller – do they make different barrel sizes for a #5 key?
No they do not. Antique keys had better brass and thinner barrels however, if it comes down to it find an antique one on ebay
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have an antique french carrage clock needing a key. To measure the square winging post to get width do I measure from corner to corner across or just one flat side corner to corner?
Flat to flat
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have an antique wall clock and need a key. The clock was made in Switzerland, any ides of the size key I need? Thank you in advance.
Do not know the answer on that one, need to measure
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a Sessions early 1900’s mantle clock with no winding key. The shafts are countersunk in the face of the clock. So, I cannot measure shaft. Does anyone know what size key I need??
Size 7 this link
https://www.clockworks.com/product/brass-single-end-clock-key
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
Hi I bought Antique Franz Hermle Mantel Clock Brass ,it came without a key I checked the back and it is engraved 10S/d
Do you think this the key size
Size 8 key is needed unless the movement itself is round instead of square, If round use size 4 unless it is a ships bell strike. If its a ships bell strike it will take size 3.
James Stoudenmire
30yr Clockmaker
Author of Clockworks.com
I have a huge Standard Electric time company wall clock and it is locked and I need the key that opens it it looks just like a winding key and I don’t know where to get one??
Sorry do not have the key for that one
James
where can I purchase a #5 key to an old American mantel clock ?
This link
https://www.clockworks.com/product/brass-single-end-clock-key
James
I have a American signature model number 58001 and wondering what size key it takes
That clock takes a size 8 key or crank
https://www.clockworks.com/?post_type=product&s=Key
Key
https://www.clockworks.com/product/brass-single-end-clock-key
Crank
https://www.clockworks.com/?post_type=product&s=Crank
James
Would you know what key would fit a 41JP mantle clock? Also has a chime if that makes a difference! Thank you
Chime and time should take the same key.
https://clockworks.com/clock-parts/clock-keys.html
Here we have clock keys in all the sizes available. We get many calls asking what key their clock takes and over the phone it is difficult to say you need key size this or that. Do not call. Best to read the below text on how to use the clock keys chart and get the correct sized key to wind your clock.
Most common sizes are as follows, these are the usual sizes and not always the situation every time.
German made round movements Size 3 or 4. If ships bell, size 3, the rest size 4
German made square / rectangle units post WW2 Size 8
German Grandfather clock cranks post WW2 Crank key Size 8
American time / strike units Size 7
Korean / Chinese 31 day units Size 7
James
I have a Pearl grandfather clock. The key for the door is missing. Do you sell keys for Pearl grandfather clocks? I have been having a really hard time finding a key. Any help would be appreciated.
This usually solves the problem =
https://www.clockworks.com/product/clock-door-key
James
Have a french marble mantel clock the face has the name lassalle on it cannot find any information online any idea wear I might find out aboutit
Please see this link for help: Identifying a mechanical clock movement — https://clockworks.crisp.help/en/article/identifying-a-mechanical-clock-movement-88buzj/
Thank you !
I need to know the wind up key size for a Poppo dog clock by Tezuka Japan
Please refer to the instructions in these links:
Mechanical clock keys — https://clockworks.crisp.help/en/article/mechanical-clock-keys-4uulkq/
How do I find a clock key? — https://clockworks.crisp.help/en/article/how-do-i-find-a-clock-key-1kue995/
Clock key size chart explanation — https://clockworks.crisp.help/en/article/clock-key-size-chart-explanation-169mtus/
How to understand the clock key size chart — https://clockworks.crisp.help/en/article/how-to-understand-the-clock-key-size-chart-10v6zxz/
Thank you !
See this link for help: How do I find a clock key? — https://clockworks.crisp.help/en/article/how-do-i-find-a-clock-key-1kue995/
Thank you !
I need to know size of wind up key for a poppy dog clock by trauma
What size winding key does IBM Time punch/recorder 1927 Chevrolet take?
I have a Waterbury cottage clock, key wide at the 11 o’clock position (no strike or chime). I’ve measured the key shaft as 3.3mm x 3.3mm with calipers. Sometimes I’ll get a 3.2mm reading. The key supplied with the clock measures 3.5mm x 3.5mm, it works, but it isn’t a snug fit. Should this clock really use a #4 instead of the #5 that came with it?
Have a Smiths Enfield mantle clock , made in England Great Britain , probably in the 1940’s have lost the key clock chimes has three areas to wind the clock any idea on a new key size ?
Most likely size 8
I was given a Forestville clock from Canada but it has no key. My Howard Miller clock key from 1995 does not fit it (key is too big). What size do I need?
I now have an International Time Recording Master Clock 65″ without a wind up key. Can you help me? Jon
Maybe
However I dont know the size off hand. Best to measure and use the chart that is right here on the key page
James
Many Thanks !
James and Donna Stoudenmire http://www.clockworks.com 124 Goss Hill = UPS Mailing PO Box 339 = USPS Mailing Huntington, MA 01050 USA clockworks@clockworks.com
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Hi, I have a Rythem Gloria clock and need a key for it. Does anyone know what size I am likely to need please?
Unfortunately the only way to get the correct key size is to measure the width of the shaft that the key is to go on in millimeters and then match it up to our clock key chart that is in the informational tab at this link: https://www.clockworks.com/product-category/all-clock-parts/clock-keys-and-cranks
Many Thanks !
James and Donna Stoudenmire http://www.clockworks.com 124 Goss Hill = UPS Mailing PO Box 339 = USPS Mailing Huntington, MA 01050 USA clockworks@clockworks.com
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The key of my carriage clock no longer winds the clock because the interior shape has worn. It is a double ended key. What size key replacement do I need? I can see no size indicator on the key. It is a Cloisonné style clock, estimate late 19th early 20th century. Thanks. Russell
I have a Taylor 668 that we use for a Gilbert Hollywood clock. What is the key size?
The only way to know what key to get is to measure the width of the shaft that the key is to go on in milimeters.
Then take that measurement and match it to the key chart that we have in the informational tabs at this link: https://www.clockworks.com/product-category/all-clock-parts/clock-keys-and-cranks
Sometimes people will get the 5 prong key set or the 13 key set if they are having troubles with measuring.
I have a Welby Westminster mantle clock and need new hands and a key
Key is usually size 8 https://www.clockworks.com/product/brass-single-end-clock-key German hands for mechanical in serpentine https://www.clockworks.com/product/serpentine-hands-for-german-mechanical-clocks
spade https://www.clockworks.com/product/mechanical-clock-spade-hands
Many Thanks !
James and Donna Stoudenmire http://www.clockworks.com 124 Goss Hill = UPS Mailing PO Box 339 = USPS Mailing Huntington, MA 01050 USA clockworks@clockworks.com
Virus-free.
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Virus-free.
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