Internet Horology Club 185
Seth Thomas Center Wheel 16j (Wanted)

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https://ihc185.infopop.cc/eve/forums/a/tpc/f/1086047761/m/1023935267

June 04, 2011, 02:12
Francis Bowman
Seth Thomas Center Wheel 16j (Wanted)
I have started the process to restore the Seth Thomas PW I have. The pivot on the center wheel on the plate side was broken off in the cannon. Now i understand what Lindel said that Staking Set are best asset one could have.I want to know how to remove the rest of the staff with out damaging the wheel.
June 04, 2011, 02:14
Francis Bowman
Center Wheel


June 04, 2011, 03:46
Eugene Buffard
It might be wiser to look for a new center wheel. There is a lot of force on this wheel. It would be hard to get this wheel re attached to a different center wheel staff. Please post a picture of the plates so others and my self can see if we have a replacement.
June 04, 2011, 05:51
Francis Bowman
plates


June 04, 2011, 06:01
Francis Bowman
David Abbe said this was 1 0f 1000 made, center wheel train plate is jeweled. I purchased a jewel guage pin set to be able to tell the size, but they will not be here for 10 more days.
June 04, 2011, 06:05
Francis Bowman
other side of the wheel


June 04, 2011, 09:39
Eugene Buffard
Can you measure across the movement. I have over 100 small watch movements. Elgins Seths,Walthams. I'm trying to narrow what parts movement you need. I have one that is 33.9 mm
June 04, 2011, 10:23
Eric Unselt
Francis, I have both types of center wheels (jewelled and unjewelled), but your pillar plate is bushed, whereas your upper train plate on that Model 2 is jewelled - making an odd center wheel indeed.

Are you sure the serial numbers match? Seth didn't make an 18-size watch with an even number of jewels.
June 04, 2011, 18:01
Francis Bowman
@ Eugene it is a size 18's model 2. @Eric all serials match on all plates. David Abbe said the same thing that since there is was only 1000 made of this model finding another wheel may be a bit hard.That is why i asked if the staff could be removed, as there is a micro Engineers in sydney whom may be able to make the staff. Two tools i do not have but are on there way is digital micros, and jewel guages.....Eric serial number on all plates "87941"
June 04, 2011, 21:56
David Abbe
Francis, I suggest that you contact the engineer with the wheel and the piece that came off in the Cannon Pinion and see what they can do. Otherwise, if you want to try to use one of Eric's wheels, I suggest the Jewelled wheel is worth a try as it could fit the bushed Pillar plate which passes the Large Staff which has to fit the Cannon pinion and is less likely to be made any smaller if Jewelled. Measure it and communicate what it is for checking.
June 04, 2011, 22:19
Eric Unselt
We're actually talking about a 16-jewel Seth here?

Cool stuff!
June 04, 2011, 22:33
Francis Bowman
@David thanks once again... my mics will be here so then i can get correct measurements on the pivots.. Eric how does one determine the amount of jewels? do the two jewels on the pallet fork count as one or two? Pillar plate has 5, in total plus two on the fork.the train plate has 4, balance wheel 1, and the balance cock 1. so 13 in total.. have i missed some thing?????
June 04, 2011, 22:57
Eric Unselt
5 total on the balance wheel - 2 cap and 2 hole jewels for the staff itself, and 1 roller jewel.

4 total for the pallet - 2 stones, and 2 hole jewels for the pivots.

8 total for the train - 2 pairs each for the escape wheel, 4th, 3rd, and 2nd (center) wheel.

17 total jewels for a fully-jewelled watch, except your is missing the dial side jewel for the center wheel.

I'd suggest starting with the unjewelled wheel. Its pivots are bigger, one of which can be reduced to fit the lone upper jewel. It'd be tough to start with the skinny one.
June 04, 2011, 23:30
Francis Bowman
On the pillar plate with the balanace wheel staff goes there is only one jewel. It is a capstone, as there is no hole for the balance staff pivot...some one took out the friction jewel.
June 05, 2011, 00:34
Harold Visser
Here's my 16J Mdl.2 Seth, center jewel is a bit different, it's a friction set.


June 05, 2011, 03:23
Francis Bowman
Very Nice Harold.thank you for sharing
June 15, 2011, 03:05
Francis Bowman
Eric my vernipers finally arrived on the slow boat from china. the pivot size are as follows. Pillar plate side 0.029in or 0.74mm
Jeweled side 0.019in or 0.48mm i took ruff measurement of the broken bit and added together to get the total length of the staff 0.446in or 11.34mm let me know what u may have there that is close to that. thanks Francis
June 15, 2011, 16:39
Roger J. Nolfe
If worse comes to worse, the existing part could be re-pivoted.
June 15, 2011, 17:18
Hub Harms
Hi,If you don't find a wheel & all else fails, E-Mail me I can probly help.
Hub
June 15, 2011, 21:08
Francis Bowman
The other seth thomas 18s i have the pillar plate side of the staff is too short.
June 19, 2011, 18:02
Francis Bowman
Roger how does one repiviot ????
June 19, 2011, 18:37
Roger J. Nolfe
Francis,

Re-pivoting is done on a watchmakers lathe and is a fairly involved and expensive process, but done properly will be as good as new. Without going into every step of the process, basically the broken end is drilled to accept a plug that is turned to the correct length and diameter.
June 19, 2011, 21:08
Francis Bowman
Roger thank you for that. I am waiting up on Eric to get back to me, if he doesnt have anything to suite then i may have to go that way around this problem to find the solution. IF any members read this and can repiviot please email me so i may ask a few questions please. many thanks. Francis
June 23, 2011, 18:35
Francis Bowman
Thank you Eric for your help, the wheel he has the staff is too short, like others that I do have if someone has one the side of the dimensions i have listed in here please contact me. Many thanks Francis
June 23, 2011, 19:18
Eric Unselt
For anybody able to help Francis, these are the center wheel dimensions for Models 5 through 12 (all 18-size):

Diameter of both wheels - 19.0 mm

Un-jewelled dial-side staff - 1.02 mm
Un-jewelled plate-side staff - 1.08 mm
Un-jewelled staff length - 10.38 mm

Jewelled dial-side staff - .81 mm
Jewelled plate-side staff - .53 mm
Jewelled staff length - 10.63 mm

Neither of the wheels I had would work in this case.