Eureka Help with Eureka clock

[timelyrestorations]

I just acquired this beauty, and had a few questions about it. I understand this clock would have been originally powered by a battery. It has been converted to a plug in. Would this affect it's collectible value? The model # is 9416. I can't seem to find any info on this particular model. Any insight? Finally, the balance wheel is fairly "sloppy" between the bearings. I see 2 small holes in the bearing plate. Would these be used (via a special wrench) to tighten up the play? Any and all help greatly appreciated.

Doug

 

[Hans Vrolijk]

These clocks were driven by a battery called "flag"cell. This type of ( very large) battery does'nt longer exist, so you'll have to use a D-cell or a wall plug anyhow.The bearings contain a paper ring, maybee these are too thick in your clock.
The book "The Eureka Clock"by dr. Shenton ISBN 0 9506761 3 6 gives you all info you need. See:
http://cheddar.cylex-uk.co.uk/company/shentonbooks-horological-booksellers-17904717.html

 

[John Hubby]

I just acquired this beauty, and had a few questions about it. I understand this clock would have been originally powered by a battery. It has been converted to a plug in. Would this affect it's collectible value? The model # is 9416. I can't seem to find any info on this particular model. Any insight? Finally, the balance wheel is fairly "sloppy" between the bearings. I see 2 small holes in the bearing plate. Would these be used (via a special wrench) to tighten up the play? Any and all help greatly appreciated.

Doug

Doug, thanks for posting your inquiry and the photos of your Eureka clock. This particular model isn't documented in any catalog nor in the Shenton book that Hans has referenced. It is similar to Model No. 12 illustrated in the 1911 Eureka Sale Catalog, but that model has a more massive case with round top break-arch design as well as ribbed quarter-columns at the front. I have documented one other with the same design having an oak case.

The use of a transformer instead of a battery doesn't affect the collectible value of these so long as there haven't been any modifications made to the original battery holder or case underneath the base. The only question I would have is what is the output voltage of the transformer. It shouldn't be more than about 2 volts, normally these run on a 1-1/2 volt battery. My solution for power is to install a 2-cell "D" size battery holder that I modify to have the cells wired in parallel. This fits nicely in the base and having two cells ensures the clock will run for more than a year before needing a battery replacement. If you would like to convert the clock back to battery power and also have what appears to be one of the flag cells that Hans mentions, they are available from Peter Smith in the UK at his Horologix website. You can also get a lot of information on service and repairs there, Peter has posted a large number of Eureka restorations in PDF format with description and photos that can be downloaded.

Regarding the "sloppy" end play you have found with the balance wheel, this is quite commonly found. Very few of the ones I have worked on have end play less than 1 mm and most between 1 and 2 mm. The clock will operate quite happily with that much end play. What happens is that the balance wheel will usually move to the back and the rear pivot will stop when it touches the steel plate that holds the two ball bearings in place, then the balance will hold that position so long as the clock is running. The position of that plate is fixed by the bearing race so there is no adjustment at that point. The paper gaskets mentioned by Hans are placed between the bearing race and the glass cover and don't affect the end play.

If there is more than 2 mm end play, the only means to reduce this is to work with the end plates and two assembly posts, This requires some mechanical adjustment that isn't easy to do so I won't go into that now as it is rarely needed.

 

[Snapper]

Without wishing to hijack this thread, I have an identical Eureka to that belonging to Doug. As John has said, it does not appear in any catalogue I have seen. The serial number of mine is 8590. Hope this is useful for John's records.

 

[John Hubby]

Without wishing to hijack this thread, I have an identical Eureka to that belonging to Doug. As John has said, it does not appear in any catalogue I have seen. The serial number of mine is 8590. Hope this is useful for John's records.

Snapper, not hijacking at all! The serial number is useful, but would really like to see photos of your clock so it can properly documented. There are individual differences that can reveal a good bit of information not available just from the serial number.

 

[Snapper]

Snapper, not hijacking at all! The serial number is useful, but would really like to see photos of your clock so it can properly documented. There are individual differences that can reveal a good bit of information not available just from the serial number.

Your wish is my command. If I have got the hang of posting images, here are pictures of my Eureka, number 8590. I hope they help with your records.

 

[Dan Mcman]

How's the value overall affected?

 

[John Hubby]

Your wish is my command. If I have got the hang of posting images, here are pictures of my Eureka, number 8590. I hope they help with your records.

Thanks much for the photos! What I got from these is the following to add to my database:

• The serial number and patent info is engraved in a thin brass plate fixed to the front of the movement frame.
• The dial is a standard "Eureka Clock Co. Ltd London" full enamel with Roman numbers and spade hands.
• The balance arbor pivots ride on two ball bearings. Some models have three.
• Your case is made of mahogany. They also made this model in oak.
• The door knob appears original, as does the rest of the clock.

Pictures really ARE worth 1000 words!

 

[timelyrestorations]

Thanks to all who replied. I now have the clock up and running after some careful examination and adjustment of the flag and silver contact pin. In response to John Hubby's query, the transformer is 3 volts. Is there a possibility of causing any damage to the clock with this particular voltage? The shelf for the original battery is still presenrt and intact. It actually sits above the movement, about midway on the dial. Not in the base as are others I have seen.

Cheers,
Doug

 

[Snapper]

Thanks to all who replied. I now have the clock up and running after some careful examination and adjustment of the flag and silver contact pin. In response to John Hubby's query, the transformer is 3 volts. Is there a possibility of causing any damage to the clock with this particular voltage? The shelf for the original battery is still presenrt and intact. It actually sits above the movement, about midway on the dial. Not in the base as are others I have seen.

Cheers,
Doug

I am pleased you have your Eureka running now. They are somewhat hypnotic in their movements.
Owing to the collapse of the magnetic flux in the coil when the contact opens and the resulting high voltage generated, there will always be a certain amount of erosion of the flag. In my opinion it is always advisable to run the clock at its correct voltage of 1.5 to minimise it. Also ensure polarity is correct with negative to flag contact.

 

[David D'Apice]

For some reason, I'm having trouble finding how to start this without seeming like I'm stepping into another thread --- but here's my challenge --- I've got this great German Eureka style, running like a top -- looks like near 360 degree rotation on 3 volts --- but for some reason, I can't get it to run nearly fast enough -- to make matters worse, I took the doggone screws out of the balance because some of them had solder under them, and of course, got confused -- not I've been fiddling with them trying to get some semblance of balance back. Any ideas on what's happening here? Here's a movie.

 

[John Hubby]

I don't recall whether the German version uses 3V or 1.5V. Have your tried the lower voltage?

Regarding the balance screws, my suggestion is to remove them again and weigh them on a postal scale to get accurate weight for each one. Pair them up by equal weight and diameter, and then replace them in the balance wheel with one of each pair on opposite sides of the balance. Screw them in until there is about a 2.0 mm clearance between the bottom of the screw head and the rim of the balance. I doubt it will make any difference in which order you replace them as long as equal weight screws are opposite in every position. I have had very little success with trying to poise one of these balances, but can see the difference in rate when the screws are moved in or out; however, that only shows up when you move all of them by say one turn.

Before working with the balance spring, first make absolutely sure the drive pawl isn't missing an impulse on any tooth of the motion ratchet wheel. That will make it appear to run slow when it may not be.

Once you are certain the drive pawl is pushing the motion ratchet wheel one tooth on each impulse, then check the rate again after having reworked the screws as above; be sure the rate adjusting gear is at its center position. If you are too slow, turn the rate adjusting gear to full fast and check the rate again. If you are still too slow, turn all the screws inward by one full turn and check again without moving the rate adjusting gear. That may bring you to time but only if you aren't that far out.

If you are still slow, you will have to shorten the effective length of the balance spring to speed up the clock. That requires that you loosen the clamp that holds the spring in place to the back plate and turn the spring in the clamp to shorten the length, then adjust the spring collet position on the balance wheel shaft. Before doing that, disconnect the battery and check the position of the balance without the flag touching the contact pin. Remember you will need to return the balance to that exact position when the effective length of the spring has been adjusted.

Now return the adjusting gear to its center position, carefully checking how far the slide contact with the spring moves along the balance spring. You will need to shorten the spring by that amount plus an equal amount to be able to bring the clock to time with the adjusting gear set at center position. Normally the slide contact will move about 3/8 inch in either direction from center position, so that would indicate the spring will need to be shortened by at least 1/2 to 5/8-inch to bring the clock to time and allow normal rating adjustment with the adjusting gear.

Now loosen the clamp holding the spring to the back plate. Slide the spring about 1/2-inch making the loose end of the spring get longer. The balance will rotate about 20 degrees from its previous "at rest" position. Tighten the clamp. Now loosen the screw holding the spring collet to the balance shaft, and rotate the balance so it returns to its original position before shortening the balance spring. Tighten the collet screw. What you should have now is that the balance will be in the correct operating position but the balance spring will have an effective length 1/2 inch shorter, which will cause the clock to run faster.

Connect the battery and restart the clock. Check the rate, which should be within adjusting range using the adjusting gear. If the clock is still slow, with the adjusting gear at full fast, you will need to repeat the above procedure except I would only shorten by about half as much. If the clock is running too fast at center position, set to maximum slow and check again. If it is still too fast, you will need to lengthen the spring using the above procedure, but again using only half the change.

Hope this isn't too confusing. The procedure is actually simple but requires thinking through exactly what changes you make to be sure the clock will continue to run properly after each change. Remember the "at rest" position of the balance should be with the coil about 12 degrees off vertical for best impulse.

 

[David D'Apice]

I don't recall whether the German version uses 3V or 1.5V. Have your tried the lower voltage?

Regarding the balance screws, my suggestion is to remove them again and weigh them on a postal scale to get accurate weight for each one. Pair them up by equal weight and diameter, and then replace them in the balance wheel with one of each pair on opposite sides of the balance. Screw them in until there is about a 2.0 mm clearance between the bottom of the screw head and the rim of the balance. I doubt it will make any difference in which order you replace them as long as equal weight screws are opposite in every position. I have had very little success with trying to poise one of these balances, but can see the difference in rate when the screws are moved in or out; however, that only shows up when you move all of them by say one turn.

Before working with the balance spring, first make absolutely sure the drive pawl isn't missing an impulse on any tooth of the motion ratchet wheel. That will make it appear to run slow when it may not be.

Once you are certain the drive pawl is pushing the motion ratchet wheel one tooth on each impulse, then check the rate again after having reworked the screws as above; be sure the rate adjusting gear is at its center position. If you are too slow, turn the rate adjusting gear to full fast and check the rate again. If you are still too slow, turn all the screws inward by one full turn and check again without moving the rate adjusting gear. That may bring you to time but only if you aren't that far out.

If you are still slow, you will have to shorten the effective length of the balance spring to speed up the clock. That requires that you loosen the clamp that holds the spring in place to the back plate and turn the spring in the clamp to shorten the length, then adjust the spring collet position on the balance wheel shaft. Before doing that, disconnect the battery and check the position of the balance without the flag touching the contact pin. Remember you will need to return the balance to that exact position when the effective length of the spring has been adjusted.

Now return the adjusting gear to its center position, carefully checking how far the slide contact with the spring moves along the balance spring. You will need to shorten the spring by that amount plus an equal amount to be able to bring the clock to time with the adjusting gear set at center position. Normally the slide contact will move about 3/8 inch in either direction from center position, so that would indicate the spring will need to be shortened by at least 1/2 to 5/8-inch to bring the clock to time and allow normal rating adjustment with the adjusting gear.

Now loosen the clamp holding the spring to the back plate. Slide the spring about 1/2-inch making the loose end of the spring get longer. The balance will rotate about 20 degrees from its previous "at rest" position. Tighten the clamp. Now loosen the screw holding the spring collet to the balance shaft, and rotate the balance so it returns to its original position before shortening the balance spring. Tighten the collet screw. What you should have now is that the balance will be in the correct operating position but the balance spring will have an effective length 1/2 inch shorter, which will cause the clock to run faster.

Connect the battery and restart the clock. Check the rate, which should be within adjusting range using the adjusting gear. If the clock is still slow, with the adjusting gear at full fast, you will need to repeat the above procedure except I would only shorten by about half as much. If the clock is running too fast at center position, set to maximum slow and check again. If it is still too fast, you will need to lengthen the spring using the above procedure, but again using only half the change.

Hope this isn't too confusing. The procedure is actually simple but requires thinking through exactly what changes you make to be sure the clock will continue to run properly after each change. Remember the "at rest" position of the balance should be with the coil about 12 degrees off vertical for best impulse.

Hi there John -- Thanks for all of this wonderful information -- I have been stumbling through these steps --- I did try 1.5V, but the balance would only oscillate 180 degrees, at best --- I notice that when I have what appear to be the smallest screws (diameter) on one side, and the largest on the other, the balance still favors (heaviest) on the one with all the small screws. It doesn't make any sense to me -- of course, trying to be a purist, I took solder out of two screws because I wanted everything to go back to original. I can't determine why the balance seems so heavy on one side, and not on the other. Perhaps some of the smaller diameter ones are actually heavier than the larger diameters? The scale should bear that theory out, right?. Thanks again.

 

[David D'Apice]

Also, at rest, what position should the pin be in in relationship to the contact flag. I read someplace "just below it" --- does that seem right?

 

[David D'Apice]

Also, at rest, what position should the pin be in in relationship to the contact flag. I read someplace "just below it" --- does that seem right?

I've made some progress today on this clock --- by advancing the hairspring position --- and by trying to get the balance wheel more "balanced", I've been able to get to within a few minutes an hour, which is a marked improvement ---- the only challenge is that it's closest to balanced when one balance screw is completely out of the wheel --- imagine that! Running on 3V nicely. I'm within striking distance. There is one side of the wheel that seemed pretty heavy when there were no balance screws in at all.

 

[James McDermaid]

I have a Eureka that is not in a catalog although the bottom of the case accommodates the battery. It was made to have the battery in there.
I use a Carlton Clock (UK) battery in mine and it is adjusted for about 2 volts.

The original battery was a 1.5 volt dry cell called a Flag-Cell in the UK and a #6 drycell in the US. Although the most common battery on the planet it is no longer made.

In the 1908 era most american cars used the good-ole #6 for ignition, Telephones use them as well as almost everything else.

I use a Carlton Clock replica which looks almost exactly identical to the #6 and it contains four type "C" cells and a regulator circuit.
I haven't replaced the batteries in more than a year.

I corresponded with Peter Smith in the UK who seems to be the world expert on Eureka clocks and I followed his instructions.

So . . . . . . My Eureka sits on my desk and I can look underneath and see the #6 for which I printed an old label for and slipped it over the Carlton battery and it looks perfect.

So . . . . . My Eureka is running on about 2 volts. They should run on 1.5 volts. I feel the original #6 delivered a more solid 1.5 volts for several years in these clocks.

The Balance rotates a little more than 360 degrees. Sometimes I have to adjust the regulator to keep it on time but for the most part it does very well. The only clock that beats it is a Atmos and my ST #1 regulator.

My house in Phoenix AZ is at a fairly constant 80 degrees and the humidity is dry. The only time I have to regulate is during what I perceive as a Barometric Pressure change..

I know the research says the balance is not temperature reactive but I believe it has to be. I believe it is also Isynchronous to a degree.

Time Savers had the replacement contact assembly and pin and Carlton Clocks has the glass bearing caps, I stocked up but I see no significant wear running on 2 volts for the past several years.

As far as I'm concerned I want my clock running on battery power as original. Eventually I will try to get it to go on 1.5 volts.

My Eureka has never stopped and is easily within seconds per day.

Jim

 

[David D'Apice]

Jim -- thank you --- I too wonder about heading down to 1.5 volts -- at the moment, the clock is keeping near perfect time --- the only issue is that one of the balance wheel screws has been taken out to get it to be balanced, which I don't completely understand --- it's the only way I can get that side of the wheel light enough -- I'm going to break out the postal scale next and see if I can swap a few things around and improve the situation --- if I could run it forever without the screw, that would be great, but the purist in me tells me to dig in my heels and go after it again! Great fun! Thank you.

 

[wisty]

David, can I chip in. Back in 2003/4 Bryan Mumford and I had a discussion about the "balance" wheel on the Eureka which was developed into a theory I presented at a UK AHS meeting regarding the screws and the wheel. What Bryan and I agreed was that the big wheel was not a balance wheel, and that the adjustment of poise was deliberately designed into the clock to allow for regulating.

My Eureka has large balance screws with three different weights (picture). Swapping light for heavy between the top (Balance wheel at the point of impulse) and bottom changes the rate significantly. Decreasing the weight at the bottom slows the clock down (and increases the amplitude). Decreasing the weight at the top (decreases the amplitude) and speeds it up.

In a "proper" clock

-----Is controlled by the escapement and provides just
| enough power to overcome the losses in the escapement.
|
The Primary Power Source (Great Wheel)
|
|
-----Also drives the hands (Time Train and Motion Work)

OK so the first couple of wheels may be in both paths, and the second hand may be driven from somewhere in same train as the escapement. But the escape wheel is always on the end of a train. The makers always trying to achieve the theoretical "free escapement" to allow the balance wheel to operate with the least possible interference. An "Escapement" balance would always be poised as perfectly as possible to minimise it's deviation from a "free escapement".

In a Eureka on the other hand

The Primary Power Source ( the battery and coil)
|
|
Drives the "Big Wheel" by magnetic impulse
|
|
Which drives the Hands via the cam, roller and push click (for want of a better word).

These two processes (magnetic impulse and mechanical push) occur over different segments of the arc of the big wheel. This means that the electrical impulse has to impart sufficient energy to the wheel to both overcome losses and provide motive power to the motion work. Energy that is temporarily stored as kinetic energy in the Big Wheel. Given this "interference" the Big Wheel is never going to be anything like a "free balance".

On the forward swing the kinetic energy in the wheel created by the impulse transfers into three places (ignoring friction and other losses) - the spring, driving the motion work, and into changes in the potential energy of any imbalance in the weight of the balance wheel. If the top is light and the bottom heavy, the centre of mass rises and gravity assists the spring in absorbing the kinetic energy of the swing so the swing is shortened. If the top is heavy and the bottom light the spring has to absorb both the kinetic energy of the swing and the potential energy released by the centre of mass of the wheel falling - so lengthening the arc. In a perfect balance wheel this would not affect the rate because apart from frictional losses the same potential energy would be converted back into kinetic energy on the reverse swing. But in the Eureka the reverse swing has lost all the energy needed to drive the motion work. This difference in energy in the two swings seems to mean that the gravity component has a much greater influence. Short arcs increase the rate and make the clock gain, long arcs make the clock slow.

Bryan and I concluded that this was deliberate design (otherwise why does the wheel need such heavy and expensive bearings) , and that the manufacturers would probably have rated production clocks by setting up a standard pattern of screws, run the clocks for a given period, then there would have been a standard table of adjustment - (e.g if 5 minutes fast swap no 3 screw for a lighter one etc, etc, etc). This would have allowed them to employ semi-skilled production workers rather than skilled clockmakers to set up the clock.

For your clock I suggest weighing the screws and then swapping them around until you can get the clock to run fairly accurately with them all in. Heavy at the top will slow it down, heavy at the bottom will speed it up. Trying to keep the wheel poised is unnecessary and probably counterproductive.

 

[John Hubby]

Wisty, thanks very much for your comprehensive description of how the Eureka "balance" wheel reacts to changes in weight position. Having worked with these now for many years I had reached the same basic conclusions but had not taken the time to do a thorough analysis as you have done. This is very valuable information for anyone who services one of these clocks, and I'm sure will resolve the regulation problems that plague these fine clocks. I'm printing your message for my file and will be following this advice from now on.

Congratulations on developing this information and thanks for sharing!!

 

[David D'Apice]

Wisty and John (and others) - thank you so much for this incredibly informative tome. I did remove each of the screws, marked where they came from -- they were all 3 and 4 gms -- no 5 or 6. Which was interesting --- I then removed the balance spring and noted that the wheel had a slightly heavy side for sure -- even with no screws -- I don't know why, but so be it --- anyway --- by the time I was done, most of the 3s were on one side, and the 4s on the other -- and surely, I couldn't get the thing to spin in balanced fashion -- it kept dropping the 3s to the bottom of the clock because they out-weighed the 4s. No matter what --- The only way I could get it to run nearly the right timing was to remove one of the 3s entirely! That was issue one.
The minute I put the last 3 in its hole, the clock would go out of time and wouldn't run nearly fast enough --- the hairspring shortening in the clamp did absolutely nothing to gain enough time. I then hit upon the idea of beefing up the 4g screws by dropping a bushing up under the head --- with the hairspring removed (again), I was able to get the wheel to roll in a balanced fashion --- once it was in balance without impulse or spring, I put everything back together again, and gave it a whirl --- it spins close to 360 and keeps nearly perfect time. I'm wondering if someone long ago put a strange assortment of screws together for this clock, but they were all 3s and 4gm, as I mentioned --- either way, it is running really nicely -- the speed regulator about mid way -- and within a minute or two in 12 hours -- I can definitely adjust speed for that --- in balance, the wheel seems to have much more life to it as well. What a learning adventure -- even though, to some degree, I had to over weight one side (about half of the 4gm screws needed the bushing), it is undetectable. I love the clock -- it's a really neat piece --- somewhere out there in the world are some 5 and 6gm screws that are orphans -- in looking at your super-helpful photos, I note that I don't have any of the heavier ones --- onward and upward -- and thanks for much for some of the most detailed, interesting responses I could hope for -- you guys really are the best. It's a super hobby!

 

[wisty]

David, I have never owned a German Eureka, so I can't be sure, but one thought comes to mind looking at the pictures of a disassembled balance wheel on Peter Smiths Horologix.com site. Has someone reassembled the balance wheel the wrong way round. with the side that is slightly heavier at the "bottom".

It would need the wheel disassembling to check, but!!

Picture is page 9 of the restoration of Eureka 404 on Eureka Gallery1

 

[David D'Apice]

Wisty -- great thought -- which I had been considering --- but even so, I still note that I only have two sizes of screws -- and none as shown in Peter's images, which leaves me a little suspect -- I'm debating whether to leave well enough alone and let it run -- it has been keeping near perfect time for me. I have half smaller diameter, and half larger diameter screws, but they are all 3s and 4s -- none completely back-filled to make them heavier - I think that's my challenge. For now, I'm holding still on my bet. If I get really ambitious, I'll start from scratch again!

 

[Ralph]

Some comments.... the German Eureka is definitely a 3V machine, unlike it's brother the English Eureka.

I went through the same thing while restoring an English Eureka. I had removed all the screws in the balance and was frustrated when I discovered it's not a simple matter of randomly or even planned reinstallation for proper timekeeping. I finally got them installed in positions where everything came into adjustment. I concluded the balance is really a form of a compound pendulum, operating on a pivot.

Mark the screws if you remove them. You will not regret it.

Ralph

 

[wisty]

As Ralph has resurrected this thread, I thought I would pass on the results of some tests I have recently run on the tall movement Eureka I acquired recently and have just got round to working on.

The clock has been stripped, cleaned and had a new flag and pin set installed ( the old one was original and all the insulation had worn away).
After reassembly the clock ran well, but was loosing 31 minutes/day, and attempting to adjust that amount out by shortening the spring caused the coils to bind. I decided to test the clock to see what effect changing the screws around would have.

This clock has two weights of large screws ( approximately 6gm and 4gm) not the three I have on my very early short movement.

I decided to swap the screws in dissimilar pairs one by one, so each heavy screw for all the other light screws and vice versa. After each swap I allowed the rate to settle down using the Microset PC interface and took the average (to 3 decimal places ( e.g. 1.334) any more precision was pointless as the rate is erratic at that level or precision.

The attached PDF gives the results. I was surprised at the range I could achieve. The rate could be varied by plus or minus two and a half hours per day simply by swapping pairs of screws. The general conclusion was ( as I suggested in a previous post) that moving weight closer to the top of the balance wheel at the point of impulse would in general make the clock run slower, while moving weight towards the bottom of the balance wheel at the point of impulse speeds it up. Changing the drive voltage between 1.5 and 2v makes a much smaller difference, while screwing all the screws in and out a turn makes changes of the order of 10-20 seconds/day.

I hope this may help people trying to get a clock to run at the right rate.

As an aside I have seen many people comment that the original cell for the Eureka is unavailable. However CPC Farnell in the UK do a very similar Alkaline manganese 1.5v 40Ah battery that has what I think are the same dimensions as the original battery. I used one to run my short movement clock until I got one of Bryan Mumford's controllers. http://cpc.farnell.com/univercell/db8014/battery-flag-alkaline-1-5v/dp/BT05682. I might invest the £15 with free delivery for one as an experiment until I can source a new controller for the tall clock.