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JMB '1016' project update...

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I started this project about a year ago but never finished it so I took another run at it recently.

Here is what was done and where it stands :

 

Standard last edition JMB '1016' case.  Probably the best affordable '1016' project case available.

Swiss ETA 2824/2846 'combo' movement.  Combo = 2824 main plates with 2846 wheel train and balance assembly.

Why the combo movement?  Because the case was made for a 2824 date movement and I wanted a lower beat rate (2824 = 28800 bph  2846 = 21600 bph...1016 was 18000 for early models and 19800 for later models).  My 2846 are all day and date models and thicker (5.2mm) than a 2824 (4.7mm).

The dial is an oem spec example that 'Stilty' got for me 6 or 8 years ago.  Pretty good dial.  Removed the dial feet for this project.

Movement was c/o and assembled, ran fine. 

The movement spacer was a good fit in the case with just a little slack.  The spacer is a good fit on the movement.  The spacer is 26.05 ID x 29.1 OD x 2.35mm thick.  The case/movement clamps were a good tight fit but pulling/pushing the crown will overcome their friction and move things around a little.

Note:  The dial mounts to the case spacer, not the movement.  There is no ETA calendar spacer used and a dial washer was used to keep the hour wheel in mesh.  The movement would mount too far toward the back of the case if a calendar spacer was used.  I tried it.

'Dial dots' were used to stick the dial to the movement spacer...dial dots were a bad move it turned out.

Drilled the case tube hole out to approximately 2.5mm and tapped it for a standard older type 6.0 ST (external spline) case tube (3.0mm x .35mm case threads).

Why?

So I could use a genuine old style 6.0mm crown.

Movement runs fine and it all looked very good when assembled.

 

The trouble...

The oem spec dial just barely has any room for centering error in the case because the dial window is 27.3mm and the dial OD is 27.9mm leaving only .3mm purchase on the outside edge of the dial to the inside of the case with the movement and dial centered.

What was the problem?  Maybe .3mm sounds like enough (and in theory it is) but with the dial mounted to the movement spacer with dial dots, the movement and spacer can move just enough when pulling/pushing the crown in and out to allow the dial center hole to rub the hour wheel/hour hand tube and stall the movement.

Why?

Because the dial dots ('slide dots'  Ha!) will allow the dial to slide on the case spacer

What's the fix?

Maybe make a precision movement spacer and cement the dial to the spacer with epoxy or Gorilla glue to hold it in place.  Filing the dial center hole out a little bit might work too but it may also chip the dial paint.  Do not want to take the chance.

 

What's next?

Nothing planned for now.  May abandon the project and move on to something else, have not decided.

If not a JMB case then what?

Maybe a genuine 160xx case but they are getting expensive and many of them suffer from corrosion.  Iirc a 2846 will work in them.  A 160x 'slow set' case may also work but I have not tried one.

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Super glue gel (gives 10-20 seconds of work time.) Three equi-spaced drops on the outside edge of the movement, then lower the spacer to set. Then same process to attach dial to spacer...

 

B

 

jLuP1EB.jpg

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"Super glue gel..."

 

Thanks, I may go with gel.  The cement needs to be just a little bit flexible so regular SG usually cracks and lets go.

 

"great write up..."

 

Thanks.  If and when I finish it, I'll post an update.

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Personally I would not file the dail as it is so easy to damage

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"Personally I would not file the dial as it is so easy to damage "

 

You are right because if it chips, the chip can be fairly large.  I have seen this happen. 

I have enlarged dial center holes using sandpaper wrapped and cemented around a toothpick mounted in a battery powered Dremel tool.  The center hole is sometimes too small for this.  Besides that, it is slow going and dust gets all over the dial.

 

The best solution is a close fitting movement spacer with the 'no foot' dial securely mounted to the spacer so nothing can move.  I did not mention that when the dial slid off to one side on my '1016', there would be an small open space where the dial uncovered the dial window opposite the direction it moved. 

 

The aftmkt dial is 27.9mm.  Just now measured a genuine 1016 dial and it is the same...27.9mm.  The dial window opening in a JMB case is 27.3mm as stated above.  Measured genuine 16200, 16233, and 16234 cases and the dial window openings are 27.5mm.  A 16014 was also 27.5mm.  Do not know what a genuine 1016 case dial window is. 

 

So...a genuine spec 27.9mm 1016 dial in a JMB '1016' case will have .6mm to play with (only .3mm all the way around the dial), and a genuine spec 162xx case will have .4mm to play with (.2mm all the way around) because of the larger 27.5mm dial window opening.

Since the dial is smaller than ideal using any of these cases in a 'not perfectly precise' project, a precision movement spacer is a necessity (JMB stated this in a previous post iirc).  No way around it.

 

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R,

 

You must have one of the early cases, they had a smaller dial seat.  The later cases will take up to a 29mm dial, lots of play but personally I like the old ones better.  When I build these I use the "low" ETA dial seat/spacer, place it on the movement, drop on the dial washer, then glue the dial to the spacer making sure I keep it centered.

 

Also, don't you mean the case is 28.3mm"  Seems it would be kinda hard to stuff a 27.9mm dial in a 27.3mm hole! ;)

 

Justin B.

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If you were to place a precision mvtspacer and you want to stick the dail onto that, what would be the best..stickers of glue? Keeping in mind that you wnat it sitting secure but removable when needed.

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"Also, don't you mean the case is 28.3mm"  Seems it would be kinda hard to stuff a 27.9mm dial in a 27.3mm hole!"

 

Dial win-der!  Like the win-der you look out of (aka dial opening).  The dial sits beee-hind it.

 

"You must have one of the early cases, they had a smaller dial seat."

 

This case will work better than a genuine (27.5mm dial opening) DJ case or case with a larger dial opening because the smaller (27.3mm) dial opening in this case gives more mounting area for the dial.

 

 

"If you were to place a precision mvt spacer and you want to stick the dial onto that, what would be the best..stickers of glue? Keeping in mind that you want it sitting secure but removable when needed."

 

Stickers (dial dots etc) and easier to deal with but do not hold the dial firmly.  Cement of some sort (epoxy, Gorilla glue etc) is better but can have so much holding power that removing the dial from the spacer may be difficult.  I will have to use glue on this particular project next time around because dial dots did not work.  Since the dial is a hair smaller than the OD of the spacer, the dial can still move around on the spacer when dial dots are used. 

On a project where the dial OD is very close to the ID of the dial seating area in the case and the dial can not move from side to side, dial dots should be Ok.

 

I did not address the problems incurred when you r/r the movement and dial as a unit and the dial (cemented to the spacer) moves around or raises up...sometimes allowing the hands to rub on the dial and/or allowing the hour hand to come out of mesh and get out of correspondence.

 

The truth is...these projects can be a real hassle sometimes.  I have done a lot of them and they do not seem to be getting much easier. 

I also work on quartz character watch projects and they are a pleasure compared to these cussed things.

 

Watch fixer Q&A:

Q...What is the difference between a pro and an amateur watch fixer?

A...The pro can fix his screw-ups. 

 

 

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