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Got hold of this very nice Record Watch with call 6112 handwind movement, beating at 28000bpm No plate loss 20 microns, gave the case and dial a clean and polished the crystal then fitted a nice ostrich grain leather strap. Any info on the movement greatly appreciated. These Watches are very underated in my opinion and may eventually go up in value.

Scouseget, When you harden metal (steel) it will be more resistant to wear, more difficult to machine, but also will become brittle and more prone to breakage. When you anneal metal (steel) it is in a softer state and easier to machine, but the yield strength (the ability to resist permanent deformation) is lowered to a point where it can become unusable for some applications. Normalizing metal is a process to relieve stresses in the metal in order to reduce warpage when it is machined. This is necessary when machining prestressed metal such as cold rolled steel. Yield strength is a critical factor to consider when machining pivots. This is the major reason the steel must be tempered. Tempering will back the steel down from a hard brittle state to a state between soft and hard. The goal is to maximize the yield strength and still have sufficient wear characteristics.This state can also be called spring hardness. This will be the metal's optimum ability to resist deformation. When pressure (cutter pressure) is applied to the pivot, it will be less likely to break. Spring tempered steel will also provide a certain amount of protection from pivot breakage in the finished product. If you have tried to machine a pivot from steel in a soft state you should notice that it cuts fairly easily but once you turn the diameter down to about .015 inches (.38mm), the pivot will bend and break under the cutter pressure. Even though the pivot is more difficult to cut when tempered to a spring hardness than with the metal in a soft state, the resistance to deformation and breakage provides a way to get the pivot from .015 inches (.38mm) down to the required .004 inches (.1mm). There are alternative ways to reduce the pivot down to the required size such as grinding it down with a stone in a Jacot lathe, but machining it this way can run the risk of getting the pivot out of round and destroying its concentricity. david

Its a Omega of course it has value, its a mid thirties stainless steel Lepine or open face pocket watch if working i would put it at about £80 to a £100, the dial is a little grotty and the bow is'nt original but clean it up its a nice watch. the calibre is a 40.6LT1 or 40.6LT2 this movement ran from 1923 to 1936.

I thought I would share my latest mishap. I was repairing a quartz (Ronda 715) which had a faulty date change. The fault was traced to a mis shaped date jumper spring. So I had to make another. I was checking it's size etc. and moved in close to get a closer look & PING straight into my mouth. I did not swallow & it did clean it up a bit I suppose.

20x magnification ! No wonder you can't see anything. You would need to be a few mm from the watch before the lense would focus. I like a head band type and use 5x for general and 8x for the fiddly bits. Sent from my SM-G920F using Tapatalk

This is a video showing the pivot turned to .01mm over the finished diameter and "burnished" down to the final .1mm diameter. This is not the only process that is used to get the pivot to the final diameter, but removing almost all of the material in the turning operation will help maintain the concentricity of the staff. Tempering steel to a spring hardness will help ensure that the cutter pressure has less chance of pushing the pivot out of concentricity due to pressure from the cutting tool. This is because the pivot has the ability to spring back after the cutter pressure is removed. A higher yield strength gives the pivot a higher resistance to strain. An extremely sharp tool and a light touch will reduce cutting pressure on the pivot but the steel will have less ability to spring back to its original concentric position. There is also the element of microscopic warping due to heat treatment after the part is turned. If the heat treatment and normalization is done before turning, the warpage of the metal will be negabile in the final product. In the end everyone has a different perspective on this subject but this is my perspective based on my background and the many failures I had when I was learning how to do this. david Here is the video: https://www.youtube.com/watch?v=mkGygB7BMsQ

It is most likely the cannon pinion. To tighten to canon pinion it is a CONTROLLED squeeze because if you go to far it is an absolute b**ger to amend. I use a Seize tool fitted with dedicated anvils for the job. If you do use the tapping with a stake or any of the other methods you most have a round rod inside the cannon for support and this helps keeping the round shape. The method I use Alternative tool. If no dedicated tool then this method

Very well described David. When reading it I was transported back to my technical college days.

Excellent post David. I suppose thats why it is recommended to use pivot steel for making balance staffs etc.

I had trouble with a ladie's oval snap back of a brand watch once. The issue was that pressing on its center distorted it enough not to fit. Once I made a wood die to press on the sides only, it went in just fine.

I may be wrong but doesn't alum only work on ferrous screws in brass or stainless plates. The ferrous screw being the component which is sacrificed? Sent from my iPhone using Tapatalk

Latest update (2nd of March); Looking back at some other pictures I took, the above mentioned hour-wheel / planetary wheel positional error didn't and couldn't have happened. It was during the re-assembly for the 2nd time, that I though that I made that initial mistake. There is "no way" one can assemble the calendar works the wrong way around without noticing something isn't right or "off". I think it was more my brain wishing to find a plausible cause for the low amplitude. To end with another positive note: the amplitude is on the rise, both dial-down and dial-up are already well above the 300 degrees Will test the movement for a few days more before installing the dial, hands and the re-casing.

longines 6922 http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&Longines_6922