Grandfather Clock Suspension Spring
Phil
original pendulum with a large (and heavier) one. The clock now runs a bit
fast, even when the pendulum is adjusted all the way to the bottom of the
regulation nut. I recently read in a DeCarle book that if the suspension
spring is too short it can actually control the timing of the clock more
than the pendulum. Does anybody have any experience with using a longer
suspension spring to slow a clock down? Also, will a longer spring give the
pendulum a wider swing?
dAz
> I have a grandfather clock with an Urgos movement. I recently replaced
> the original pendulum with a large (and heavier) one. The clock now runs
> a bit fast, even when the pendulum is adjusted all the way to the bottom
> of the regulation nut. I recently read in a DeCarle book that if the
> suspension spring is too short it can actually control the timing of the
> clock more than the pendulum. Does anybody have any experience with
> using a longer suspension spring to slow a clock down?
no deCarle is talking about older clocks like the english bracket clocks,
modern clock movements like the urgos have a preset length in the
suspension springs, specially if its that black plastic moulded one, you
will not be able to change to a different suspension spring without
drastic modifications to the pendulum hanger and crutch
anyway the suspension spring is not your problem, the pendulum is too
short, if you have fitted one of those ugly lyre pendulums there are at
least 3 different lengths and sizes availible.
you will need to either change the pendulum for a longer one, or add a
piece of brass to the pendlum hook end to make it longer, if its just a
bent over hook, straiten it out or cut off the hook, and fit a strap of
brass the same width and bend it over to make a new hook, you should rivit
the strap on rather than just soft solder for extra strength.
> Also, will a longer spring give the pendulum a wider swing?
no, that has all to do with type of escapement, amount of wear and
condition of the oil, a softer spring might increase the arc but again
only really affects short pendulum clocks
besides a wider swing might be bad idea, on a few clocks I have serviced
with those pendulums there isnt a lot of room between the case sides and
pendulum bob, in fact on one job I had to level the case more upright
because the bob was hitting the glass panel of the case on one side
The Baron
A thicker spring will give less swing and the clock will run slower. In
your case you are mostly limited by what the manufacturer has available.
If you had a longer spring then you might be able to change it's shape to
that of an ''hour glass'' but this would only make it run faster. A
reduction in thickness of the spring changes it by it's cube. Length is
just linear.
"Phil" <spri...@dejazzd.com> wrote in message
news:VVxN8.14188$Q43.3...@nnrp1.ptd.net...
dAz
> A thinner spring will give the pendulum a greater swing and slow the
> rate. A thicker spring will give less swing and the clock will run
> slower.
that really only affects short pendulum clocks,
>
> If you had a longer spring then you might be able to change it's shape
> to that of an ''hour glass'' but this would only make it run faster. A
> reduction in thickness of the spring changes it by it's cube. Length
> is just linear.
>
> "Phil" <spri...@dejazzd.com> wrote in message
> news:VVxN8.14188$Q43.3...@nnrp1.ptd.net...
>> I have a grandfather clock with an Urgos movement.
this is an Urgos, probably similar to the one that I am working on now,
then he can only use the same type of suspension from the maker since a
standard suspension spring won't fit
http://members.optushome.com.au/daz7/horological/Urgos-Suspension.jpg
and yes it will get a new suspension spring when I finish it ;)
The Baron
clocks and I would not call them short.
"dAz" <da...@nonspam-zip.com.au> wrote in message
news:3d0819a1$0$21003$afc3...@news.optusnet.com.au...
dAz
> That depends upon what you call short. It works on both 80 and 60
> beat clocks and I would not call them short.
>
>
mantle and bracket clock size, 5-6 inch pendulums, as to longcase size, it
might affect a light wood stick pendulum, but on an old english longcase
with a solid lead bob the suspension spring thickness is not much of a
factor, same with those lyre pendulums on todays clocks, they are pretty
heavy so again the suspension doesnt affect the arc of the pendulum much,
more to do with the type of escapement fitted, a recoil would give a
better swing, but seeing that there isn't much room in the cases with
those lyre pendulums is probably why most have deadbeat escapements fitted
The Baron
swing. This means that a dead beat will swing less than a recoil.
Still, with in these confines, a change in spring thickness will
increase/decrease swing and rate. This is especially true with an
English or German wall or tall case clock. I have ''repaired'' many such
clocks in my 35 years. Wall clocks are notorious for running 90 beat with
no place for the pendulum to go except through the bottom of the case.
This type of clock is usually purchased from a flea market, boot sale, ebay
''it runs'' or dealer wantabe.
Tall case clock pendulums often hit the sides(or nearly so)when obtained in
the same fashion as wall clocks or possibly an owner modification.
Our differences here reflect our experiences or that each of lives near a
different pole of the planet.
"dAz" <da...@nonspam-zip.com.au> wrote in message
news:3d083374$0$21005$afc3...@news.optusnet.com.au...
dAz
> I will agree that the type of escapement will affect a given amount of
> swing. This means that a dead beat will swing less than a recoil.
> Still, with in these confines, a change in spring thickness will
> increase/decrease swing and rate. This is especially true with an
> English or German wall or tall case clock. I have ''repaired'' many
> such clocks in my 35 years. Wall clocks are notorious for running 90
> beat with no place for the pendulum to go except through the bottom of
> the case. This type of clock is usually purchased from a flea market,
> boot sale, ebay ''it runs'' or dealer wantabe.
>
>
>
yeah I agree with that, but I think its a combination a short suspension
spring and a light wood stick hollow pendulum, the suspension spring
thickness does affect the swing and rate, I just find on english style
bracket clocks and long/tall/grandfather clocks made before 1880s where
the suspension is fairly long as in 3-4" and a very heavy solid lead
filled bob that the thickness of the suspension spring doesn't seem to
have much effect.
and yes I get those marriages, movement ment for a dial clock in a drop
dial case or visa versa, they seem to come from India or Indonesia where
they don't give a stuff if its the right movement or not, so long as you
say "it runs"
> Tall case clock pendulums often hit the sides(or nearly so)when obtained
> in the same fashion as wall clocks or possibly an owner modification.
or after a service!!
>
> Our differences here reflect our experiences or that each of lives near
> a different pole of the planet.
that too!, the water swirls the other way going down the drain here ;)
Phil
a lot today!
"dAz" <da...@nonspam-zip.com.au> wrote in message
news:3d0937a1$0$21004$afc3...@news.optusnet.com.au...