Suspension spring for 1969 Kundo pendulum clock

kdkevindraper

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Hi can anyone help me with the details of replacement suspension spring please. I disassembled the clock and cleaned all the parts but the suspension spring has either sheared off or come loose from the bottom block.
Attached picture of front and back plates.
Thanks
Kevin

20201228_161400.jpg 20201228_171629.jpg
 

KurtinSA

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Looks like plate 1407H. Guide calls for 0.0022" suspension spring. Seems we had some recent discussions on a similar back plate Kundo.

Kurt
 
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kdkevindraper

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Hi Kurt.
Thanks yes it's the same clock. I just wanted to reconfirm now I have it in pieces. Do I also need to know the working length of the spring? I can measure the length of the broken one and assume it's sheared off.
Thanks again.
 

KurtinSA

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Yes, measure the old one but account for the amount that was lost and/or still stuck in the blocks. Cut it longer than needed. You can always trim it once you assemble. This is where the guide helps. As a point of reference, the guide shows about 64.5mm in between the blocks...that doesn't include what is captured by the block. Do you measurements from the broken spring...see how it compares.

Kurt
 
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Dells

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Hi Kevin
You can order replacement torsion springs from H S Walsh or Cousins both in uk just do a Google search.
Ps best to get Horolover torsion springs
Dell
 
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KurtinSA

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Thanks, Stan. I dropped a critical zero. I might get a moderator to change it so it's not sitting there forever giving wrong info!

Update --- OK, a moderator made the change. All is good!!

Kurt
 
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kdkevindraper

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Thanks everyone. I was puzzling over the thickness last night. Current spring measures 0.002" with Vernier. I have ordered a pack of Horolovar wires from HS Walsh
 

kdkevindraper

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Hi thanks for your help so far. Everything is cleaned and reassembled. However fitting the new suspension spring is a learning experience.

Could you give me the distance from the top block to the fork please. I didn't record this when I took the clock apart so I'm working from a photo. I've had the clock working but the fork was fluttering which I believe means it was too low.

I assume it's better to screw the fork onto the spring when it's flat rather than after it's in position. I'm onto my 3rd spring now so need to try and get the fork position right first time. However I might still need to fine-tune the fork position, is there a recommended way of holding the fork while moving it?

Thanks
 

KurtinSA

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The gap between the top block and the fork is shown as 3.5mm in the repair guide. That is often too small and I routinely increase that as I work on the clock. Start with 4mm and go from there.

As for adjusting the fork position, I have a piece of wood, likely a 1"x4", where I've drilled a small hole towards one end. I use this to work on the suspension spring once it's been removed from the clock. The small hole is where the pin on the bottom block goes if there is a pin set into it. Then, with a good pair of smooth jawed pliers, I grab one side of the fork as it lays on its side. Firmly hold the fork and carefully loosen the set screw that pinches the fork against the spring. Once sufficiently loose, I can then slide the fork up/down with my fingers...measure to the new position I'm looking for. Back to the pliers, hold the fork and tighten the screw. The screw doesn't need to be ham-fisted torqued...it just just needs to be snug enough so it doesn't move.

Kurt
 

kdkevindraper

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Thanks Kurt I get it. I marked out on card the hole positions for the top and bottom block holes and used pins to help me get the blocks fixed around the spring. I didn't fit the fork at that point which it seems was an error. So do you always remove the suspension spring before changing the fork position?
 

KurtinSA

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Yes. There's very little chance of successfully move the fork up/down the suspension spring without creating some damage or ruining the spring. I've been somewhat successful in spreading the fork tines with a screwdriver by holding with my fingers the one side of the of fork while in the clock, but I know that one of these times that's going to bite me.

Just discovered that the clock I'm working on is fluttering because I moved the fork too low. Here's my setup getting ready to grab the left side of the fork and loosen the screw.

Kurt

ForkAdjust.jpg
 
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kdkevindraper

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Hi Kurt, that's really useful thanks.
Following your suggestion I've made a jig with two pins to locate the blocks when fitting a spring or fork. Overkill for one clock i know. Clock is now running although not in beat if i understand the term. There is a slight kink in the spring between top block and fork. I want to learn about getting in beat before I use my 3rd spring.
Thanks
 

KurtinSA

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The spring between the fork and top block is pretty critical, so kinks or twists can affect the clock's performance. That said, I have clocks with a kink or maybe it's really more like a bend in the spring which I've bent back a bit...not sure where those clocks are in my collection but I don't think that made a difference. Anyway, you'll have to make the decision regarding that. But kinks or twists change the stiffness of the spring which is all important to the clock running.

Kurt
 
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whatgoesaround

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You often can switch the positions of the top and bottom blocks. The kink is much less critical in the bottom portion of the suspension than between the top block and fork. If the kink is tight against the top block, you could also move it into the portion of the top block that holds the spring and adjust your distances accordingly.
 

kdkevindraper

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Hi I took the plunge and fitted my last new spring. However the clock is still not running smoothly and stops after 20-30 minutes.
Pendulum spinning clockwise - anchor pin starts at the right, moves smoothly to the centre, gives a slight click, makes a slight move to the left, CLICK jumps back to the centre. No over-run.
Pendulum spinning anti-clockwise - anchor pin starts in centre, goes right a little, CLICK, jumps back to centre, goes smoothly all the way right (long over-run)
So there are a few jumps in the movement. I tried setting in beat (as I understand it) by rotating the saddle slightly but the pattern of jumps is still the same.

Could you look at the pics of the escapement wheel and anchor please. 3 teeth seem to be at a different angle to the others, but that wouldn't account for the jumps being on every rotation. I'm not sure what a healthy wheel would look like. Also the tips on the anchor pallets are different shapes.

Thanks

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Wayne A

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Looking at the escapement picture its a little hard to see due to being taken at and angle and its rather grainy. Not sure if I see bent teeth or its the shadows playing tricks. Anchor pallets angles are typical, cannot tell if its adjusted properly.
Under normal conditions the anchor pin will have small jumps when the drops occur, jumping at other times are ushally fork to pin friction or worn notches in the pin or fork.
 

KurtinSA

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Seems strange to have so much of the pallet sticking above the anchor. I know that happens from time to time, but this might suggest that the pallets and eccentrics have been mucked with, creating a un-running situation.

Kurt
 

whatgoesaround

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If by overrun you mean the continued rotation after the anchor has released off of the escapement then your differences in overrun would indicate that it is not in beat
 

MuseChaser

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Definitely make SURE the clock is exactly in beat before messing around with adjusting pallets or bending the tongue. I'm a beginner compared to lots (most) folks here, but after renovating fifteen torsion clocks in various stages of neglect and disrepair, it's become painfully obvious that the beat being adjusted improperly is the primary cause of many ills. I've only had one clock that needed escapement adjustment, and the deep gouges around the eccentric adjustment were a prerty good clue that a previous owner or even less-skilled repair person (if there is one) had hacked it up.

Oh...and.... just buy the Terwilloger book. It more than pays for itself on your first repair, it's excellent, and fascinating to just leaf through if you have an interest in the history and workings of these clocks.
 

kdkevindraper

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Hi, thanks everyone for your help and guidance. In the end I didn't need to adjust the pallets or escapement, just set the fork to exactly the distance in the repair guide (3.5mm) and a tiny adjustment to the saddle. It's been running smoothly for over a week now, about 3% fast, so I'm going to start calibrating. It's really heartening to come across people ready to help.

20210116_161437.jpg
 
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