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Tools required for an Antique Long case?


Endeavor

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You have a point with the dial of course ! If you start on one part, then the other part looks like it needs too. Once the dial is done, then the whole clock-case looks like it needs at revamp. Once the dial & whole clock-case are done, then suddenly the room and furniture in which the long-case clock stands start to look worn & shabby, and so the story continues ....... :D

It's indeed an art when not to add / fix or touch. To leave things alone, "as is" ........

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Here are some pictures of the escapement and escape-wheel. It is clear that work has been done to the escapement. One can see some wear on the surfaces, but one can't feel groves with the finger-nail. The teeth of the escape-wheel seem fine too, but the tops of the teeth are worn under a slight angle, the highest point being towards the back of the clock, the lowest point towards the front of the clock. Not that easy to get a clear picture. If the wear on top of the escape-wheel teeth is the result of 300 years, I guess all is fine and no need for interference.

Best is, in my humble opinion, to assemble the clock and see how the escapement and escape-wheel engage. The tolerance in the front bushing is fine, so if the escapement needs some correction in height, the "dubious" rear-bushing has to be changed out. Included are some pictures of the double rear-bushing, mounted in the rear-bracket.

Escapement-1.thumb.jpg.9a4c4374bb52d21989eafa2fee515b8b.jpg

Escapement-2.thumb.jpg.452fe4979762ef6e44e1ad407559edb4.jpg

Escapement-3.thumb.jpg.dd22e3120ea967639a549081154f1898.jpg

Escape-wheel-1.thumb.jpg.9b964153abf30f150797a8768970c2d7.jpg

Escape-wheel-2.thumb.jpg.b276c70c67d338ef03650f6b304cbe1b.jpg

Bracket-1.jpg.affe01e64eac5c64619b30f71a04f0e0.jpg

Bracket-2.jpg.21f1676476d1449e6587b860e26f70b6.jpg

 

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The escape wheel might well be a problem as you say see how it runs. I made a big mistake a few years ago with a escape wheel like yours. I straightened the teeth as best as I could then trying to be cleaver I run it on my lathe running a burnisher over the teeth to get them all exactly the same height. Result it would not run, I had removed too much material.   B*gger or words to that effect were said.  

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Those pallets have been re-faced and that escape wheel is worn. That pallet cock has been altered; the screw hole has been filed into some sort of miss-shape to compensate for wear. Altogether, it is one hell of a mess.  

Clockboy you tried toping with a difference. When it comes to the escape wheel the very minimum should be undertaken, if the teeth have a lip on them just address the tooth with a small  arkansas stone to remove the burr.

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You need to set the going train up and study the action of the escape wheel against the pallets and in turn watch the action and swing of the pendulum. I expect the swing of the pendulum to be very poor. You also need to watch the recoil. This is when the clock escapes the seconds hand moves a little backwards, this is best watched with dial fitted and seconds hand fitted, it should be the same with every second past, I’m expecting it to be very odd as the escape teeth look to have different lengths. You only have recoil with anchor escapements never deadbeat escapements.

You need something to put the movement on to test. A piece of wood with a hole drilled near the top, hand it on a large screw that has been screwed into the wall and two L shaped brackets screwed to the wood. Movement fitted to the seat board. Seat board rests across both L shaped brackets, make sure the brackets are big enough so the pendulum can be fitted and is free to swing. You need to make sure the wood does not move when winding the single weight. I used to drive a nail into the wall to stop it moving after making sure it was level.

 

This is a link that shows animation of a recoil.

 

https://commons.wikimedia.org/wiki/File:Anchor_escapement_animation_217x328px.gif

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@oldhippy; Yes, that all makes very much sense to me. Thank you ;)

I'll also study the clocks long case itself as I noticed some scores on the wood inside the case, at the height where the pendulum weight swings. The pendulum weight itself also hung a bit "off".

To make a decent stand and setup for the clock is no problem, but it's going to take some time. I least now we can zoom in to a specific problem. Obviously I'll now study the ins & outs of deadbeat escapements as it now became apparent to me that previous clock-makers have gone through great efforts to correct the wear situation. What also became apparent to me is that they all concentrated on either the escapement self, the pallet-cock or a combination of the two, i.e. not the escape wheel self. This "tells" me that the escape-wheel is the very last to be touched.

I do agree with you that the pallet-cock has seen some delicate & "cruel" treatments, but it is still in one piece and therefor I do assume that it is still usable and a good starting-point for whatever comes next.

"I'll will be back" as soon as I have some more findings to report.

All very interesting & educative indeed !

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We'll see how and where this project goes.

One step at the time and before anything gets done, each & every step has to be thought through. If it turns out that this project is more than I (or we) can chew, the clock goes back to the owner in the same condition, or in a better condition than as I received it. Regardless the outcome it will be very interesting & educative.

Needless to say that I hope for a positive outcome ........

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Tomorrow I will get the bottom part of the case. This saves me making a special stand and the clock will be in its "own environment", which suites me better.

I did put the going train together. The pallet cock has on one side a "centering"-pin, the other side it has none and because the screw hole on that side has been enlarged, the cock can one-sided be slightly adjusted in height, and thus so the height of the anchor. With the cock in the lowest position (and so the anchor), when putting power (by hand) on the train, nothing moves and the pallets of the anchor seem to "dig" themselves into the teeth of the escape wheel. However, if I position the cock in the highest position (and so the anchor), the escapement seems to work, with very little power applied to the train, with gusto and seemingly flawlessly .....  Of course the crutch is free moving and has no resistance.

According to Wikipedia the anchor escapement seems tolerant of large geometrical errors in its construction. The recoil is seen as a disadvantage as it causes extra wear in the whole wheel-train. It is also a frictional escapement, the pendulum is always being pushed by an escape wheel tooth throughout its cycle, and never allowed to swing freely.

Once I have the clock setup in its case, the pendulum and weight attached, we have to see how the anchor-escapement performs "under load"....... to be continued ......

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I've some clock repair books to go through, but also found some other interesting material about the mechanics of clock- & watch-escapements, design criteria, etc :  www.orologiko.it/pdf/EscMechanics.pdf

Try to catch up with Oldhippy :)

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For whatever it may be worth; with the pallet-cock in the highest position, the clock runs at the moment very nice & regular. The seconds hand, and the (visible) escape-wheel have a very slight recoil on either side of the tick. The original clock weights are 5.9kg each. Currently the clock runs, without any auxiliaries attached to it, just the going train, very happy on a 1.25kg weight.

Now it's time to study the ins & outs of an anchor escapement, so I hopefully get a better understanding where I'm looking at and where to look for. Try to figure out what the situation is with the pallet impulse face's, angles, depths etc.

The pdf-link above is already good theoretical help/understanding.

 

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I forgot to mention about cleaning Longcase clocks. You will need a lathe for some of the work; it is possible to do some by hand but can be difficulty.  I start with the screws. All the screws should have all the burr removed and polished. Start with a fine needle file and move through the grades of emery sticks finish with the finest I used crocus paper, don’t forget the other ends of the screw if the ends show polish them, if the screws are square a smooth jaw vice or something to hold the screws is needed. All the steel work should be polished not just the wheels also all the striking parts right down to the hammerhead. Do not forget the barrel arbors, clean off any burr and polish the squares and the tips of the arbor and the rear, also the tip of the centre wheel, your emery sticks will do this also one other, pumice powder dipped in petrol and use an old toothbrush or a washing out brush, which you can buy from clock suppliers. Pumice powder and very fine steel wool work well together to clean all the brass, do not forget to brush in between all the teeth of the wheels and don’t forget the bell nut if it is brass. Pivots should be clean, tidy, and burnished. Pallet faces if not too worn should be polished with fine emery stick making sure you polish a flat surface. The weight pulleys and if the pendulum is brass should be cleaned in the same way as other brass work. The suspension spring should be inspected for signs of kinks or other blemishes it should be flat if not replace it. Anything that needs to be pinned should have a new steel pin with the ends tided and rounded off at the thick end. When all the cleaning and polishing has been undertaken all the parts are cleaned out in petrol and dried in sawdust, when dry brush the sawdust away with a clean brush, a blower is also handy, don’t forget the insides of the barrels as well.  

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Thank you very much @oldhippy ! I'll certainly use this as a reference if we get to that point.... I would then be delighted to do the final touches.

Just now, to say it gently, there are some hurdles to overcome. The more I catch up in theory, the more I see, discover and question (the usual "enlightening": the more one learns, the more one realizes that one knows next to nothing :) ).

Even though the clock ran seemingly fine on a 1.25 kg weight, one could hear, after some studying how an anchor-escapement supposed to work, that there were troubles. To assist in clear communication, I took the liberty to give things some names (in the hope that I named them correctly);

Pallet-1.thumb.jpg.ea7c2b72eb8d6c8e13b781ff006c3b20.jpg

Above we see the anchor, on the left the Entry-pallet and I named the sound, when a teeth of the escape wheel makes an impact on the entry pallet, the "tick". On the right the Exit-pallet and I named the sound, when a teeth of the escape wheel makes an impact on the exit-pallet, the "tock".

Even though the beat of the clock sounded right, about the same time between the tick and the tock, the tock sounded louder than the tick. This means that the impact forces on the pallets were different and in this case the teeth on the tock had a greater impact on the exit-pallet than a teeth tick on the entry-pallet.

Measurements with a feeler confirmed this (the "drop"). The drop between a teeth and the entry-pallet, at the moment that the exit-pallet released, was 0.35mm. The drop between a teeth and the exit-pallet, at the moment that the entry-pallet released, was 0.9mm.

5a5cd34114bf1_Palletplay.thumb.jpg.897ac849bc2fc2bba47c1f76bfe6c412.jpg

This means that it takes longer for a teeth to hit the exit-pallet after release, than it takes for a teeth to hit the entry-pallet after release. This in turn means that the impact forces on the exit-pallet are much greater, and therefor the wear will be much greater. It also means that there is an inequality in the amount of energy being given to the pendulum on each beat.

Preferably, to minimize the wear, the impact forces should be equal and kept to a minimum. The impact forces are in turn a function of the distance the teeth travels freely (the drop) between release and impact (the greater the distance of free travel, the more speed the teeth develops) and the torque applied to the escape-wheel. The torque is a function of the weight hung on the clock minus all the friction in the gear-train etc. The greater the weight, assuming the friction being equal, the more torque on the escape wheel ..... so the "running"-weight should be kept as low as possible as well.

Looking at the anchor self, it seems that the anchor is slightly warped on the entry-pallet side. This most likely caused the tilted wear on top of the escape wheel teeth;

Pallets-2.thumb.jpg.6b13772d7756b212a679b95f27002f44.jpg

To make matters worse, for as wear is concerned, both pallet surfaces are not polished, never mind burnished. Hopefully you can see on the picture the file marks left behind which are running from left to right .... the worst possible direction for causing wear.

Here the exit pallet;

Pallet-3.jpg.a34e7174bef8c6200495427d6919a0a2.jpg

and here the entry-pallet;

Pallet-4.thumb.jpg.3779d2272c74a2b7e670bc0334b96496.jpg

One can also clearly see, that due to the warped anchor-arm, the escape wheel teeth impact imprint on the pallet is off-center. Whereas on the exit pallet it is nearly in center.

If I, as I've done before, move the pallet-cock to the lowest position, the situation becomes even worse. The drop between an escape wheel teeth and the entry-pallet becomes 0.2mm and between an escape wheel teeth and the exit pallet 0.8mm, making the difference in sound between the tick & the tock much more pronounced.

Perhaps there are many options left, but the ones I currently see:

1) The anchor needs a serious rework, to straighten, increase in pallets thicknesses (meanly the Exit pallet, but also some to the entry pallet, so there is some "meat" for polishing and burnishing the surfaces)

2) A complete new set of escape wheel, cock and bridge (CousinsUK sells complete sets)

3) Leave it as is an the clock goes back to the owner, with a list of spotted defects. The clock will run for some time to come, but we now know that it will stop at some point in time due to wear on the escapement.

If either option 1) or 2) is chosen, I have to see what that all entails and whether I can do it? Option 3) is currently the last option I like to opt for ...... but wisdom is also to recognize one's maximum capabilities.

Of course, there is the owner of the clock which needs to be informed if serious work & cost are on the table.

Hope to receive some advice, idea's & other options on how to proceed .......

 

 

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Clocks that work by weight should never have weight increased this can and will cause unnecessary wear to the whole movement.

Inequality might not be just down to the pallets it can also be the wear of the teeth, pivots, pinions and the pivot holes. Just because the pallets and escapement wheel work together where we have, a combination of both does not mean the fault lies just there. The pallet faces should be square on to the escape teeth. If not this will cause wear to the one side of the teeth, which in turn will cause a bad entry and exit, which will cause the pendulum not to swing, as it should? I have seen this happen due to extensive wear which in turn causes the escape wheel to trip (many teeth escape at one time)  The pallet ends should both be straight so even exit and entry happens. Another bad practise is a repairer will move the position of the pallets to the left or right of the escape wheel to avoid a proper repair.

An excellent

document you have. It shows you have been reading the correct books. You certainly understand the escapement.    

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Thanks @oldhippy; yes, after writing the article above it became clear to me that even if option 1) was chosen, that the "fix" would tackle only a part of the problem, not the whole problem. All the previous "fixes" done to this movement also focused on just a part of the escapement-problem, not the whole. Fixing a part of the problem will be relative short lived as well. I decided that this was no longer an option for me. One does it either right or you don't do it at all.

Today, I had a discussion with the owners and it has been decided that the clock will be cleaned, assembled, oiled and optimal adjusted with all its flaws. The clock will most likely only run on special occasions and therefor it may last for quite some time. I told them an easy to remember analogy: it's like driving an old car by which you now know it has an engine problem; it may brake down today, but if you drive it carefully, it may do you another 50,000 km ...... ??

after which they can still decide to do a proper full-restoration or not. Now for them, after having looked at a still-standing clock for 20 years, they not only get a clock back which runs, but also a well detailed report of what my findings were. It's now up to them to take at a later date action upon those points.

For me it's now a matter of assembling, oiling, adjusting, see if I can get the date & moon working and installing the "missing" moon-indicator. A test run and thereafter it's back to the owner.

Disappointed ..... not really. I learned a lot and for me, I stopped in time. Rather a running 18-century clock and well informed owners than knocking on the door with a plastic-bag full of parts and a message: "I'm sorry" ........

Thank you all for your excellent help !! :thumbsu:

 

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