John Wilding Elegant Scroll Skeleton Clock

[Marcus BowmanParticipant @marcusbowman28936]

John Wilding's depthing tool is a simple but useful tool. Plans were included in the BHI Journal around 1979 or 1980, as I recall. It was in the instalments of the first of three clock designs intended to be made on the Unimat 3 (or larger lathe, of course). The clock you are building was also published in instalments in the BHI Journal, as most of John's clocks have been. That's perhaps the source of the reference to the "1st series".

I made that first clock, which was based on a 16th Century one-handed clock, and I made the simple depthing tool as well. The DT design has appeared in several places since then, I believe. And others have published similar designs of DT too.

Marcus

[Neil WyattModerator @neilwyatt]

Posted by Russell Eberhardt on 13/02/2017 09:59:12:

The John Wilding type is much easier to make!

Russell.

Yep, but the OP needs a tool that can depth gears already fitted to their arbors.

Neil

[John WallettParticipant @johnwallett97180]

Hi Marcus thanks for the reply

The measurement that is giving me concern is the 1 5/32" it measures 1 7/32" plus the pattern for the rear plate cut out is different from the front profile!

John.

[Marcus BowmanParticipant @marcusbowman28936]

One of the problems with the dimensions is that while they are all in imperial units, cycloidal gears are usually dimensioned in Module (M), which is a metric measure.

42DP is approximately the same as 0.6M, but not exactly. So if you convert calculations based on 0.6M to imperial units, there is a small error. The same would be true if you did it the other way around, of course.

Using the Thornton's guide to wheel and pinion cutters,

Module (M) = twice the centre distance in millimetres / sum of teeth in wheel and pinion

Or: centre distance = half of sum of teeth x M

= 98 x 0.6 = 59.8 giving a centre distance of 29.9mm

1&5/32 is 29.36875mm and 1&7/32 is 30.95, so you can see that either imperial figure is a compromise and, as the drawing says “approx”.

It is not unusual to vary the depth of cut on a clock wheel, just a little, so I would use a 0.6M cutter, and increase the depth just a touch. That ‘touch’ could probably be calculated from the Thornton’s guide, or perhaps by using Gearotic (which I think now includes cycloidal gears). That thins the teeth slightly, but not enough, in this case, to cause a problem.

I have seen a clockmaker’s depthing “tool” which allowed meshing to take place without disturbing the dividing setup used to cut the teeth of the wheel, so that the correct depth can be judged at that stage. They are not common, and would not be required for this job, although one would be jolly convenient.

It would be worth calculating all the centre distances, as a check, to see if any others need a slight adjustment, or if the errors cancel out as you progress up the train.

Marcus

[Marcus BowmanParticipant @marcusbowman28936]

The pinions for this clock are stated as being "best" made out of blued pivot steel. I disagree strongly. Pivot steel/Pinion wire has a poor finish on the surface. Try abrading it lightly with a very fine paper, and you will see the surface is like a ploughed field. The wire will be uncut, so that's not going to provide the low-friction surface you need. Carbide rod or HSS rod would be much better.

Marcus

[roy entwistleParticipant @royentwistle24699]

John. If you were to make a depthing tool as the John Wilding pattern and instead of having points, Drill holes the same size as the arbours through the adjustable screws you could depth the wheels and pinions then put a point made from the same stock as the arbours through the screws and mark out that way. ( I hope this makes sense, I know what I mean )

Roy

[John WallettParticipant @johnwallett97180]

Thanks Marcus that has given me a bit to ponder over and I hope it all resolves it's self when the Depthing Tool is sorted!

Thanks Roy that is a thought !!!

John.

[John WallettParticipant @johnwallett97180]

Hi guys back on trying to finish the clock!! I have got to the stage of the plates all done not polished the train is done and running, the bit I am stuck on is fitting the strike components there is no mention in the book I have of how to fit them? can anyone help with either a scan of the section covering this or sell me the latest edition IF it covers this? my edition is No4. Thanks John.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Marcus Bowman on 14/02/2017 09:27:29:

The pinions for this clock are stated as being "best" made out of blued pivot steel. I disagree strongly. Pivot steel/Pinion wire has a poor finish on the surface. Try abrading it lightly with a very fine paper, and you will see the surface is like a ploughed field. The wire will be uncut, so that's not going to provide the low-friction surface you need. Carbide rod or HSS rod would be much better.

Marcus

.

Marcus,

Please permit me to question your strong disagreement.

Blued pivot steel is a raw material, from which things are made

… It is not intended to be used 'as-is'

MichaelG.

[Marcus BowmanParticipant @marcusbowman28936]

Posted by John Wallett on 18/02/2018 09:02:30:

the bit I am stuck on is fitting the strike components there is no mention in the book I have of how to fit them?

Does your edition have Fig 114 showing the bracket in which the hammer is to be pivotted? The bracket is to be fixed to the front plate with 2 screws. The 3 sections of the bracket can be pressed together or soldered.

The trip pin on the minute wheel should be approximately 4mm (5/32&quot in from the edne of the wheel, andf aligned with the minute hand. Make the lifting piece over length, then trim it so that release occurs exactly on the hour. I would take care to allow enough material to remain so that the arm can be given a final polish but still release on the hour. Longcase clocks often have bent pins to compensate for wear…

Fig 116 should show dimensions of the lifting pin. The pin is held on the shaft using an M1.8 x 0.35 (10BA) screw, bearing in a flat on the arbor (also shown in fig 116).

The tail of the hammer arm rests against the stop block on the bracket (shown on the un-numbered fig. entitled 'bracket components' and shown in the photograph Fig 115a. I am guessing that photo may have been a later addition, as it shows the assembled parts. Fig 115 itself shows the Parts of the "one-at-the-hour" striking gear.

Marcus

[Marcus BowmanParticipant @marcusbowman28936]

Posted by Michael Gilligan on 18/02/2018 09:30:08:

Blued pivot steel is a raw material, from which things are made

… It is not intended to be used 'as-is'

Yes; but my objection is that it is widely recommended for use in the as-supplied condition when making lantern pinions. If the surface is polished, that reduces the diameter, which then means the specified matching drilling diameter is wrong. Lantern pinions have merits of their own, but, when used instead of cut gears, the blued pivot steel is used as a convenience, so one would expect the drilling diameters to be correct for the finished diameter of the rod. That diameter is variable, if the rod is polished or turned.

More modern materials may be more expensive, but are dimensionally more accurate, and have a surface finish which means they can be used as-is. They are also harder than pivot steel. I guess pivot steel was the most convenient workable hard material 100+ years ago, but I am inclined to move with the times, except when restoration demands the use of age-appropriate materials.

Marcus

[Michael GilliganParticipant @michaelgilligan61133]

Thanks for the clarification, Marcus

MichaelG.

.

P.S. For small lantern pinions, decent quality sewing needles make very good trundles.

[John WallettParticipant @johnwallett97180]

Hi Guys I have moved on a bit the clock is all rough assembled not polished yet!! anyone any idea of what the click spring on the barrel looks like? again nothing in my book! I can do something to do the job but would like to do it as it should be. There are a lot of things missing in the book like how/where the bracket for the alarm is fitted, the maintaining dent arbour no mention of that either etc etc

Thanks.

John.

[RJWParticipant @rjw]

Hi John, the ratchet on the mainspring barrel doesn't have a spring, the pawl is initially held away from the ratchet teeth during initial setting up, then engaged and locked tight once the mainspring pre-load is set, it isn't moved again unless necessary to reset the spring preload,
The mainspring is then wound via the fusee cone which winds the chain/wire off the barrel, the barrel arbour always remaining stationary

The spring on the fusee wheel holds the ratchet pawl against the teeth on the ratchet wheel adjacent to its train wheel, this can be fashioned out of strip brass, a common repair on antique longcases and fusees when they work harden and break,
I'll have a dig into my repair archives and try find an example,

John.

[John WallettParticipant @johnwallett97180]

Hi John that's great thank you and it all make sense any info is much appreciated

Kind Regards,

John.

[RJWParticipant @rjw]

Cheers John, I've found some photo's of a replacement spring I made for a longcase movement I Restored, it was for a 5 pillar 8 day 'Pinchbeck' clock with a small 'refinement' not normally seen on run of the mill stuff, so it may suit the skeleton, I'll get them into my albums and post them up for you.

John

[John WallettParticipant @johnwallett97180]

Hi Guys I finished the Elegant Scroll clock and it keeps excellent time but will not run for 8 days! I got the latest book and it says there wasn't enough resilience and the barrel should have been made larger ie 2.250" doesn't say inside or out? the simplest method is to make the Fusse smaller but doesn't say by how much?

Anybody done the modifications?

Regards,

John.

[James MakiParticipant @jamesmaki45168]

Posted by John Wallett on 09/01/2019 20:59:02:

Hi Guys I finished the Elegant Scroll clock and it keeps excellent time but will not run for 8 days! I got the latest book and it says there wasn't enough resilience and the barrel should have been made larger ie 2.250" doesn't say inside or out? the simplest method is to make the Fusse smaller but doesn't say by how much?

Anybody done the modifications?

Regards,

John.

Going off my copy of the book, in the BOM it lists:

• 1x 2" length of 2.25" OD by 3/32" wall thickness brass tube for the barrel.

I'm still in the process of modeling the clock in CAD before I start building and don't entirely have my head wrapped around his diagrams for the fusee assembly (and there aren't any real great pictures of it that I've found so far) but his dimensions of the fusee are:

• Small End: 11/16" OD
• Distance from Small to Large End (including flat): 1.5" (flat length 1/8&quot
• Curve profile: 2.2" Radius

That being said, I'm currently trying to determine if that small radius is correct, since the same page shows the Fusee Stop as having an 13/16" diameter basis, and not the 11/16" diameter the diagram above it appears to show

[Bob StevensonParticipant @bobstevenson13909]

I can' find that title among the wilding books….. There is the ':Large wheel skeleton clock' book mentioned at teh start of this topic and there is 'How to Make a Skeleton clock' isbn; 0 9503512 21 1

 

Inn the latter book mentioned above the first chapter is headed; "an 8-day Skeleton Clock". Several members of Epping Forest Horology club have made the clock successfully and I have not heard of any 'duration' problems. However, I have made a set of wheels, barrel & fusee recently to use in another clock of my own design…..there are many inaccuracies, gaps and problems in the book that I have found, and in fact will not use a wilding design/publication again for this reason. Among our members the wilding books have attracted increasing criticism in recent years….so questions;…

 

…….A couple of years back Wilding published an article on 'Horological Journal' mentioning that his fusee patterns would benefit from being smaller but did not intone by how much!

 

1) What isbn number are you working from?

 

2) How long does your clock run for?

 

3) What is the actual title of your book?

 

4) in mentioning a bigger barrel,, did your book happen to mention a bigger spring?

 

 

Edited By Bob Stevenson on 07/01/2020 22:38:19

[James MakiParticipant @jamesmaki45168]

Just to be clear, the values I posted above are from this book:

• Title: The Construction of an Elegant Scroll Frame Skeleton Clock (and Mainspring Winder)
• Store: http://iantcobb.co.uk/e%20skeleton.html
• If there is an ISBN or other publication number associated with this book, I cannot find it.

Looking at the notes section in the front, I now see the following:

"It should be noted that the correct strength of spring to drive the clock is one of 0.45mm thickness, height 38mm and 50mm diameter. This is a standard mainspring available from suppliers"

He then goes on to say in the next paragraph:

"If perhaps due to lack of freedom in the train the clock will not run on a spring strength of .45mm and you have to fit a .5mm spring then you will need a larger barrel. This should be 2.5" OD, 3/32" wall thickness. There is plenty of room in the frames for this size of barrel. The spring diameter will then be 63mm"

In the actual text of the book, he says that the 0.45mm spring would run the clock for 8 days, and the 5mm for 7.5, but it's not clear if this text was updated along with the note, or the note was added and the original text left alone, so it's still not very clear.

I think I personally, unless someone else chimes in with experience to the contrary, am going to default to the 2.5OD by 3/32" barrel with the .5mm spring since it looks like his diagrams have also been updated to match, but this doesn't really help anyone in the short term since I'm a long ways away from knowing if this will yield an 8-day clock. This is both my first clock and first workshop project, so I'm taking my time.

[Martin KyteParticipant @martinkyte99762]

Mine will run happily for the 7 days between windings. Regarding spring strength modern springs are stronger than the old plain carbon springs for the same dimensions.

On my clock the stopwork engages before the mainspring is fully wound so there are a few more turn available. A slightly finer pitch on the fuzee grooving woould give you some extra turns. Another thought is if the fusee has been made with too much meat in the middle that would reduce the going time as would the point where the line starts and stops.

Just to clarify things and ask a stupid question. The clock is stopping because it has run out of line and not because it runs out of torque isn't it? In other words has all the line been unwound from the fuzee?

regards Martin

[John WallettParticipant @johnwallett97180]

I ended up putting micro bearings / bearings on all arbours apart from the pallet, I made the larger barrel 2/14 " and the smaller arbour 0.5" and I sourced a 0.4mm spring and the clock keeps time within a minute a week with the weaker spring the pallets are having an easier life!

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