Hello, I'm Oliver Cook, I'm a curator of horology here at the British Museum
and welcome to my corner.
So first of all, I'll take off the weight because we don't want that clattering around
and the counterweight too.
Now I can safely take the clock off the stand
and you can see on the back here
there goes the door
there's our little bracket for hanging it on the wall.
So first of a ll I'll take the side door off
and then I will take the hands off
and the beautiful thing about this clock is I don't need any tools at all
to take it apart put it back together.
So now the dial should come off
and I will now take these front wheels, this is what we call the motion work
these wheels are behind the dial and these drive the hands from the main mechanism.
So I'll take those off
and then I'll take the back of the clock off
we have little pegs in here to come out.
There we go.
Put that up there.
So we've got the clock down to its bare bones now
so we can see a bit more what's going on
I think I will sit down now because it'll help.
So I said we'd have a little look at the striking train
this is the mechanism at the back here
so if I put this wheel of the motion work back on
which is necessary to do this bit.
So the minute hand is on this square here, so it goes round once an hour
and this pin you see here comes up as we get towards the hour
and starts lifting this lever which we call a nags head
because it's a bit like an nags head and you'll see it nodding in a minute
and as we get up to the hour, your striking train will be released.
Now looking on the back of the clock
obviously somehow the clocks got to know how many strikes to strike at each hour
three strikes at three o'clock, four strikes at four o'clock and so forth
and to do this it uses this device here which we call the count wheel.
What you'll notice, it's got little slots around the edges that as we go around have space increases
that's the basis on which it counts if I if I set the clock off again
and lift the lever you'll now see this pin coming up
and every time you see that lifting you'll hear a dong on the bell
if the bell was on this clock but it isn't
so you see their little pin there feeling for the hole but if it doesn't get it it lifts up again
until it finds the slot and then the striking stops
and that's how the striker system works.
Other systems were devised but they needed more parts
but one of the benefits of what came after the rack and snail system
is that you could set a clock to strike on demand by tugging a cord
which was very useful at night because obviously you can't see the time at night
unless you have a night clock but that has its own problems
such as causing buildings to burn down.
Okay so now let's take the clock apart and have a look at some of the components a bit more closely.
So I think I'll take off that count wheel first.
Just need to pop a pin out
and there we have it
you'll see on the back of it is another wheel
which is driven by this small little pinion here
Now I think I'll take the top off
It's the next stage. There we go.
And now you can see the balance wheel a lot more clearly
and the lid band running around the edge
So lets just... we can run that again
just so you could see the clock running.
Now we will take that out, off we come, and there you see the verge
these are our pallets that I showed you earlier, which are part of the escapement
and now with the escapement out if we decide we want to run the clock
it will just spin through freely.
Now we need to take our striking set off lever out so another pin to come out
and we've got this rather lovely little latch here that comes up
there we go
there's our nags head.
Now let's put this on it's back
take the rest of our motion work off
and this is rather lovely, little wooden wedge at the front here just slides up and out.
Okay now we can pop the front train bar out
and then out comes the going train
here's our escape wheel with the pins on it
and I think I'll leave the rope in the clock for the purpose of this exercise
but we unhook it from the great wheel and out comes our great wheel
and there you can see the pulley that the rope sits in
and when we're winding the clock
that's the clicking you're hearing, that little ratchet there
and when the weight is released the ratchet engages and tries to pull the wheel around.
So that's our going train out. Now turn the clock over.
Again let's pop the wedge out here
take the rear train bar out
and out comes our striking train
and this is again this is the great wheel of the striking train, similar to what you just saw
some broken teeth here, that's perhaps one drawback to wooden geared, a wooden wheeled clocks
is that the teeth are more fragile.
And here on this side you see six pins and these drive the hammer that strikes the bell.
and here at the top of the train is actually a fly
and that's doing the job of the controller in the striking train.
It's helping regulate the speed at which the striking is happening
its by no means far removed and actually even from the balance wheel we've just seen on the going train
but all it needs to do is slow the train down enough so that we can count on the stripes.
So there we have it; our clock is now in bits.
That was the easy bit now I'm going to try and put it back together, so here we go
Now we're ready to hang the clock back on its stand
and the moment of truth will it still tick?
the counterweight on first
Whew!
So there we've taken this lovely clock apart and put it back together again without any tools
and it was still ticking at the end.
Thank- you for watching and if you liked this video
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