Conversions (clock and watch key winders)
- clock / watch keys are special order, that means you cannot return them. Please check that you are ordering the correct sizes (see the charts below).
- we order from the manufacturers overseas so please allow 3 to 5 weeks for delivery.
- postage is £6.75 per order (for the entire order), it is the same whether you buy one key or a few hundred.
- you must tell us the size(s) you require (see below). I know it's tempting to ask us which size will fit your clock but there really is no way of us knowing. Scroll down to see how to measure it.
- we were getting a few enquiries per month (every month) asking which size to buy, even though it was clearly explained that you need to follow the instructions on how to measure the clock (its winding peg) and look up the key size on the chart - see below for details. Each enquiry involved a few email exchanges.
- 80% of customers only ordered one key which, after labour, postage and packaging, left us with no profit.
- 30% of customers still managed to order the wrong size, so they returned it (at our expense) and we sent them the correct size (at our expense).
CONTENTS
CLOCK KEY CONVERSIONS
WATCH KEY CONVERSIONS
INTRODUCTION
In the days before winders were fixed to clocks and watches, you would wind them with a separate key. Clock keys are also used to wind music boxes, automatons, Meccano motors, metronomes, and as radiator bleed keys (the standard keys that come with radiators aren't strong enough for jammed-up bleed-valves).
There are 18 sizes of clock key and 14 sizes of watch key. To find the key number, measure any edge of the winding square ("peg") in the clock or watch (in millimetres) and look up the charts below. The most common sizes are the middle sizes, so you could take a gamble and order, for instance, clock key sizes 6, 7 and 8, but it would be more accurate to measure the winding peg.
The European numbering system is standard these days, and that is how our keys are marked, but you can see all three scales (European, English, millimetres) on the charts below.
There's a picture of the different styles of keys at the bottom of this page - scroll down.
CLOCK KEY CONVERSIONS
(for watch key conversions, scroll down slightly)
If you have a clock and have lost its winder, measure any edge of the square winding peg in mm (i.e. measure the peg that is inside hole, not the hole)
EUROPEAN SIZES
** ORDER THESE SIZES FROM US **
| Eur. | 000 | 00 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | Eur |
| mm | 1.75 | 2.0 | 2.25 | 2.5 | 2.75 | 3.0 | 3.25 | 3.5 | 3.75 | 4.0 | 4.25 | 4.5 | 4.75 | 5.0 | 5.25 | 5.50 | 5.75 | 6.00 | 6.25 | 6.50 | 6.75 | mm |
BRITISH SIZES
** IGNORE THIS CHART **
- unless you are trying to match the Key Number on an antique key, this system of numbering is no longer used.
| GB | 000 | 00 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | GB |
| mm | 2.00 | 2.2 | 2.4 | 2.6 | 2.8 | 3.0 | 3.2 | 3.4 | 3.6 | 3.8 | 4.0 | 4.2 | 4.4 | 4.6 | 4.8 | 5.0 | 5.2 | 5.4 | 5.6 | 5.8 | 6 | mm |
Still confused?
Forget about the different systems of numbering keys,
just measure it in mmm (millimetres) - all millimetres are the same.
Looking for a radiator key?
The butterfly-handle keys give good leverage, used by plumbers when it's stuck:
size 10 should fit perfectly, but size 11 if it's been painted over.
(Watch key conversions are below)
WATCH KEY CONVERSIONS
|
EUROPEAN KEY NUMBER
* * ORDER THESE SIZES * * |
SIZE IN MM
|
BRITISH KEY NUMBER
Found on antique keys |
||
|
00
|
2.00
|
12
|
||
|
0
|
1.90
|
11
|
||
|
1
|
1.80
|
10
|
||
|
2
|
1.75
|
9
|
||
|
3
|
1.65
|
8
|
||
|
4
|
1.60
|
7
|
||
|
5
|
1.50
|
6
|
||
|
6
|
1.40
|
5
|
||
|
7
|
1.30
|
4
|
||
|
8
|
1.20
|
3
|
||
|
9
|
1.15
|
2
|
||
|
10
|
1.05
|
1
|
||
|
11
|
1.00
|
0
|
||
|
12
|
0.95
|
00
|
For most uses choose the butterfly-handle type (there are two in the picture) or the smaller of the two crank-handle types. The crank-handle with the wooden knob is for winding up the weights of longcase (Grandfather and Granddaughter clocks). If the hole is particularly small you may need the long-stemmed key (the chrome one in the picture). The double keys are for carriage clocks, one side of the key is for winding the spring and the other for turning the hands. The multi-key is meant to be for traders to measure the size before buying the correct key, but some use them as 'all-purpose winders'. Watch keys only come in one style, the picture shows an entire set, they are also available individually.
Please email us for prices.
Please read the paragraph at the top of this document before emailing.