Hairline crack in porcelain dial

A

Alan_Jones

I have a hairline crack in porcelain dial off a Japy Freres 8 day movement. The crack is between the winding arbour hole and 3 o’clock and appears to have been caused by careless replacement of the movement in the bezel. The crack originates at the small indentation in the dial that lines up with the bezel retaining pin.

The question I have is there something that can be done remove the dirt from the crack to make it less noticeable. I have heard that soaking in a bleach solution or a Bio Tec washing powder solution but I am nervous of doing more damage. Any advice other than full restoration or replacing the dial?

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A

Alan_Jones

I have a hairline crack in porcelain dial off a Japy Freres 8 day movement. The crack is between the winding arbour hole and 3 o’clock and appears to have been caused by careless replacement of the movement in the bezel. The crack originates at the small indentation in the dial that lines up with the bezel retaining pin.

The question I have is there something that can be done remove the dirt from the crack to make it less noticeable. I have heard that soaking in a bleach solution or a Bio Tec washing powder solution but I am nervous of doing more damage. Any advice other than full restoration or replacing the dial?

193.jpg
 
K

kenknox

I have good luck cleaning them in an ultrasonic cleaner with a mild soap solution. Do you have a product called "Tarnex" in England? That would work also if used with a toothbrush and a good rinse afterwards.

Kenny
 

jkfabulos

NAWCC Member
Aug 21, 2001
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One must be extremely careful putting these in an ultrasonic as many times the porcelain is loose from the underlying base metal and gets destroyed leaving you with much worse problems.If it truely is just a surface fracture the ultrasonic does a good job but since it is difficult to determing the extent of damage below the crack use caution.
I have also had this unpleaseant experience with glass mercury pendulum tubes that sometimes shatter in the ultrasonic. Why exactly one does and one doesn't I do not know but suspect internal stresses in the glass may be the culprit.
 

Scottie-TX

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Apr 6, 2004
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I haven't tried all but I've experimented with many - detergents, acids, lyes - clorox, etc. to no avail. I don't recall trying Tarn-X however and I don't have an ultra so those two might be good bets. I DO know Tarn-X has excellent cleaning properties on porcelain.
 

Chris Radano

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Feb 18, 2004
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First I would try a soft cloth dampened with water, maybe a mild dish soap. If the chapter ring, and numbers are not fired in, this is relatively safe. I have an 18th century porcelain dial, where the numbers were fired in. It is mounted by brass rivets on a circular iron piece. The movement is pinned to the dial assembly, and hung by a post on the back of the dial assembly inside the case. There are many hairlines in the porcelain around the rivets. I got great results by wiping off the porcelain with water, the applying a quality liquid wax on the dial. Looks good to me! Start slow, or you may damage the dial further.
 

Kevin W.

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Apr 11, 2002
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alan, i have had had very good luck with polident denture cleaning tablets.I soak my porcelain pocket watch dials in this.It does not hurt them and makes them look much better.When it removes the dirt from the hairlines, usually hard to see them after.
This method works good for me and soak for a few hours, take out have a look.If it needs more time, soak then check.When finished rinse with water and let dry.
Good luck.
 

RJSoftware

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Apr 15, 2005
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Does anybody remember the porcelin paint that the old hardware stores usta sell?

Not sure if they still sell it. They usta advertize a sink half painted with the stuff and I believe the paint was somehow as hard as porcelin...

RJ
 
K

kenknox

Yes RJ I remember it..I moved into this old house and they used it on a chipped sink and its all yellowed and dull now. I bet it looked good for awhile though,

Kenny
 

RJSoftware

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Apr 15, 2005
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Hey Kenny;
Just curious. Do you remember if it was softer than the porcelin?

I seem to recall that it had simular hardness. Probably could not feel difference with fingernail but you could most likely scrape it with a knife edge.

I wonder if anybody still sells it. I think it would be a great thing to wipe into porcelin crack. Might be perfect for those hairline cracks. For that matter I could use it on my sinks :)

On the other hand, maybe just a dab of acrylic paint would do the trick for the dial. That way you could at least blend the right color.

I would be tempted to take the dial in to Lowes or Home Depot and let them do the color analize thing. It's probably not pure white.

Then have them mix up a pint...

I did that for Welch clock dial that was bad shape. But porcelin is different story. When the guy mixed the paint for me, he then asked if it was ok. I wished he had not cause the computer probably had it right, I messed it up a bit and wound up a touch too light.


RJ
 

SSWood

Registered User
Sep 27, 2004
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Like Veritas, I've used denture cleaner (Steradent), on pocket watch dials, and on porcelain clock dials, with excellent results. I've also used Hydrogen peroxide ( applied with a cotton bud ). In each case, rinse carefully with clean water. I've also used Fairy Liquid , but note , it leaves the hands as soft as the face .
 

Ingulphus

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May 29, 2006
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I've used a mixture of beauty-shop strength hydrogen peroxide (20 or 40 volume) and powdered hair bleach (i.e. Clairol's "Simply Blonde", which is also a good measure of my mental faculties) on stained antique china with great success. I have heard, however, that the mix can damage red glazes - I've only used it on a blue and white pattern.

The peroxide and bleach are mixed to form a thick paste, which is then used to cover the stained area. With heavy staining, I put the piece in a zip-lock bag - as long as it remains wet, it continues to bleach. I've left pieces overnight with no damage to the glaze, but in your case I don't think you'd need to leave it on very long - I would start with 5 minutes, rinse it and see what progress was made. After it's been rinsed off, a vinegar rinse will neutralize any residue.

As Chris Radano mentioned, there's a possibility that the numerals and chapter ring aren't fired into the glaze, in which case even too much rubbing with plain water could damage them - I see there's some damage to the "11". You might want to mix up the bleach and using a paintbrush, apply some at the outer edge of the dial (the area normally hidden by the bezel) as a test.

Good luck!

Mark Powers
 
K

kenknox

Hey RJ,

Yes the repair was as hard as the porceline it seemed. Not sure but it looked like an epoxy paint. I believe they sell a similar product at appliance stores. I wouldnt use it on a clock dial though. I would rather have a crack than a bad looking repair attempt.

Kenny
 

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