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clockmakers_b2e07b
02-01-2011, 04:21 PM
Recently several rebuilt clock movements have come back several years later, and we are finding that one bushing has turned a rusty red color and has chewed up the pivot and frozen in place. We use L&R cleaning solutions in our ultrasonic tanks, 859 oil, and the American made bronze bushings, Bergeon size. Typically we will only find one bushing that this has happened to, even if we have installed many more. We are thinking that the oil and bushing are having a reaction of some sort. We are certain the oil is good and fresh. It has happened on American clock movements and German alike. Has anyone else had this expierience, or is this something we are having a problem just within our shop?

harold bain
02-01-2011, 04:26 PM
Hi, clockmakers_b2e07b, welcome to the message board.
You don't mention what you use for a rinse. Whatever this problem is, it hasn't been reported before on the message board. But it sounds like the movement has some kind of residue left from the cleaner causing this reaction. I would consider changing cleaners (I use Deox 007, with a hot water rinse, hot air dry).

lpbp
02-01-2011, 04:59 PM
Are you polishing the pivots?

Dave B
02-01-2011, 06:43 PM
I have been using L&R 677, followed by a water, then an alchohol rinse. I have been using that combination for about five years now, and have experienced no problems. But, I polish the pivots after I clean the movement, and install any new bushings only after all the pivots are tended to. And I do not handle any clean parts with my bare hands. I wear nitrile gloves.

Willie X
02-01-2011, 07:18 PM
cloc,

The bad ones wouldn't happen to be made of bronze, would they?

Willie X

Thyme
02-01-2011, 08:53 PM
cloc,

The bad ones wouldn't happen to be made of bronze, would they?

Willie X

I'm thinking along the same lines. Bronze is not the same as brass.

shutterbug
02-01-2011, 09:29 PM
Yeah, I believe he said they were. But only some of them show the problem.

Willie X
02-02-2011, 07:18 PM
When bronze does battle with hard steel the results is often something that looks like rust. The pinion will oft be frozen in the bush to a point that the clock stops. More often in the lower part of the clock than the top. This is fairly common in late model Hermles with hard pivots and bronze bushings (second wheels). IMOE in Hermles it happens shortly after the lube goes away.

Many clock repairers (me included) don't like to use bronze bushings because they tend to eat up a pinion (in a hurry) at the slightest provocation. Although, if you could guarantee that the oil would never leave, I think that the bronze would last longer.

Willie X

Dave B
02-02-2011, 11:44 PM
I have used bronze and brass bushings essentially interchangeably with no appreciable difference in results. I have never experienced the problem described. But then, I have only been putting bushings in clocks since about 1980, and most of the clocks I have worked on were more than thirty years old before they came to me with worn bushings and pivots.

itbme1987
02-03-2011, 09:13 PM
After cleaning and drying i use tooth picks held in a pinvice and use that to clean out the pivot holes, that should get out anything missed in cleaning and rinsing.

Neeth
02-04-2011, 05:02 PM
I've run into that problem two or three times. I don't do clock repair as a full time job; I'm retired so it's more like a hobby that earns some money. The two times I recall that problem have had one thing in common. They were both on a wheel that had the wheel and pinion right next to the pivot so that almost all of the force exerted on the wheel was born by the pivot in question. Both had that hard brown substance that reminded me of auto body filler putty (Bondo) with tiny sparkles mixed in. The cleaner I was using would soften it but wouldn't remove it. In one case the pivot had worn into a dumbell shape and was firmly trapped in the pivot hole. I had to clean the plate with the wheel in place to soften the "stuff" so I could remove the wheel. The pivot was reduced to 15-20 % of the original diameter. Then I proceded to snap off a twist drill in the hole as I was trying to do my first repivot. :mad:Then there wasn't room enough to use an arbor cap and pivot. This was NOT a job I was real proud of.:eek: Fortunatly it was my clock, so I called the person doing the repair an idiot and thouroughly lambasted his lack of skill and pointed out his fumblefingered machining skills. Then I kicked him out of my house.:@ I'm told he's still afraid to try another repivot job, so.... I guess he took my rantings to heart.:rolleyes:

Ken W

shutterbug
02-04-2011, 05:23 PM
I castigate my repairman on a regular basis too, but he's too thick headed to let it bother him :)

harold bain
02-04-2011, 05:27 PM
Ken, and SB, my boss is a really great guy who accepts my imperfections:D.
It's great to be self-employed:Party:

Neeth
02-04-2011, 05:31 PM
Thanks SB and Harold, before I let my repairman try another repiviot I'm going to ask him to get lots of advice from you guys.

Ken W

Hayson
02-04-2011, 09:23 PM
I had to smile at the anecdotes above. It did ring a bell. We've all done clumsy things and I s'pose the trick is to try and learn from them so you don't have the humiliation of having to give yourself another talking to!
As far as the dry pivot problem is concerned, I think the most likely answer is just that, they are dry and probably always were. What is being described sounds very much like a dry pivot which has picked up some moisture from condensation, started to produce a little rust (practically the same thing as jewellers rouge) and proceeded to grind itself to oblivion producing more rust dust and brass particles as it goes. Even if you thought you oiled every hole it is possible that the oiler missed and left most of its load in the side of the oil sink instead of in the bearing. Whenever I've seen pivots like this they have been the only ones with not a trace of oil in an otherwise well (sometimes too well) lubed clock

clockmakers_b2e07b
02-18-2011, 12:51 PM
:)Sorry I haven't responded sooner to all of your great replies. To answer a couple of questions, first. We use L&R #112 cleaner and a naptha petroleum based solvent rinse. We have used it over 20 years with no problems. And yes we polish all pivots. We have used Bergeon bronze bushings for many years (15+) with no problems. It has just been sporadically with in the last 2 years or so this problem has come up. It is typically the second wheel pivots. We did have one Hermle movement recently that this occurred in, that had factory installed bronze bushings. What is strange is installing 6 bronze bushings in the second wheels of a Westminster movement, but the only one affected is the rear plate time second wheel, no others. This has also occurred in some American time and strike movements, but not often. The only change we have made in repair is using American made bronze bushings. The only explanation I have is that the pivots are getting scored from the bronze bushings, and they in turn are chewing up the bushings, which creates a rusty colored paste of oil and ground bronze. Maybe the answer lies is using Brass American made bushings, maybe they will do the job and last longer.

Tinker Dwight
02-18-2011, 04:30 PM
Hi
Are you sure it isn't rust?
In automobiles, when there is a location that gets
poor lubrication, I see a pasty looking redish
material that is a mix of rust and old oil.
It is the same as jewelers rouge with old oil added.
Tinker Dwight

Hayson
02-18-2011, 07:12 PM
Hi
Are you sure it isn't rust?
In automobiles, when there is a location that gets
poor lubrication, I see a pasty looking redish
material that is a mix of rust and old oil.
It is the same as jewelers rouge with old oil added.
Tinker Dwight

We're on the same page Tinker.

MARK A. BUTTERWORTH
02-18-2011, 08:23 PM
This is another example where the only guaranteed solution is bearings in the 2nd wheels where ther is so much force. If I did not mention it before, Hermle will be putting bearings in their 2nd wheels on the Urgos UW03 line starting sometime this year.

Willie X
02-18-2011, 08:38 PM
Rust? I think that the residue looks a lot like rust but is simply powdered bronze. None of the clocks that I have seen had any evidence of rust, as in oxides of iron.

Willie X

Hayson
02-18-2011, 11:51 PM
Rust? I think that the residue looks a lot like rust but is simply powdered bronze. None of the clocks that I have seen had any evidence of rust, as in oxides of iron.

Willie X

You've never seen a rusty pivot Willie??

Willie X
02-19-2011, 07:49 PM
I've seen rusty pivots by the thousands but never seen a single rusty pivot in a movement where all the other pivots are not rusty. Moisture, from any source, would affect all the pivots along with other steel parts.

Only thing that could cause isolated rust would be something like a drop of sweat, spatter of soldering flux, etc.

Willie X

Hayson
02-19-2011, 09:10 PM
I've seen rusty pivots by the thousands but never seen a single rusty pivot in a movement where all the other pivots are not rusty. Moisture, from any source, would affect all the pivots along with other steel parts.

Only thing that could cause isolated rust would be something like a drop of sweat, spatter of soldering flux, etc.

Willie X

The other cause of a rusty pivot which you've omitted to mention, is the one which I detailed in my earlier post (#15), examples of which I have seen on a number of occasions. I've never seen a clock which had all rusty pivots, although I'm sure this can happen in isolated instances when a clock has become wet or has been stored for long periods in damp conditions. This implies that the "thousands " of rusty piovots are all due to "a drop of sweat, spatter of soldering flux, etc." I would have thought that the occasional dry pivot due to being missed during oiling was a more common phenomenon than either of the aformentioned causes.

MARK A. BUTTERWORTH
02-19-2011, 09:29 PM
Possibly it is a case of a single pivot being missed during oiling. Or maybe that individual pivot was not mirror polished. We have seen on a number of occassions one pivot in bad shape and the rest of the clock looks grreat. Most recent example is the Urgos UW03 series time wheel 2nd front pivot hole wear.

Kevin W.
02-19-2011, 09:37 PM
Is this a chromium plated pivot?

Hayson
02-19-2011, 10:11 PM
Is this a chromium plated pivot?

I think we're talking in the abstract, about the general rather than the specific Kevin. But it doesn't really matter. I think plated pivots will lose their protective coating and begin to rust in an aggressive environment too.