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screwdriver size for SM 300 case clamps

  1. VictorAlpha Apr 15, 2014

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    This is my first post so please forgive me if this is in the incorrect forum, I did a search to no avail. I am the proud owner of a SM300. I got the movement in good condition several years ago and recently was able to order the case parts via the local Omega service agent who then assembled it for me.

    There is a slight smudge and some fine scratches on the underside of the crystal as if someone cleaned off some dust, left a smudge and then tried to wipe it or polish the inside of the crystal with a contaminated cloth. I have tried to ignore it to no avail. In most light it is invisible but in some light it really stands out. Instead of sending it back I want to have ago at lightly polishing it and cleaning it thoroughly. If that fails I'll have to order a new crystal and send it back with a note confirming my OCD.

    I have opened the case-back and removed the crown stem, however I've been defeated by the case clamp screws! The slot in the screw is too fine for any of my screwdrivers. Does anyone here have any idea what size driver I'll need for thee and can I get it from Ofrei or Esslinger? Any advice would be most appreciated on this!
     
  2. Alpha Kilt Owner, Beagle Parent, Omega Collector Apr 15, 2014

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    Tbh send it back. Without wanting to knock your skills do you really want to risk damage by just "having a go" ?
     
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  3. VictorAlpha Apr 15, 2014

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    No doubt you are right. Problem is I hate sending something back only to find that it has not been rectified or worse something else is wrong. There is also a risk in postage.

    My ability may be rudimentary but removing a movement is a relatively straightforward task. Worse case the crystal needs to be changed anyway. Thanks for the suggestion nonetheless. :thumbsup:
     
  4. Archer Omega Qualified Watchmaker Apr 15, 2014

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    Typically it's a 120 (1.2 mm) screwdriver, but that depends if the correct Omega screws were actually used. Of course expecting screwdriver blades to fit right out of the box a bit optimistic. Blades often must be dressed to fit the slot of the screw you are working on at the time, so even if you order a screwdriver of the correct size, it will still likely need a touch up to the fit the slot properly.

    Can I ask if you have ever removed and installed a movement in a watch before? If not, I seriously suggest you send it back to the person who assembled it, or find a competent watchmaker to do the work. While this is a very easy task for a watchmaker, for someone who has never done it there are many opportunities for you to do damage.

    Are you absolutely sure the marks are on the inside? Have you tried polishing the outside of the crystal just to be sure it's not scratches on the outside that you of course just can't wipe off?

    Even if the marks are on the inside, you won't have to replace the crystal - the crystal can be polished on the inside as well.

    Cheers, Al
     
  5. woodwkr2 Apr 15, 2014

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    Here's a tutorial on screwdriver sharpening: http://members.iinet.net.au/~fotoplot/sdriver/sdriver.html

    Al's a pretty nice and helpful guy. I'll be a little more blunt (pun intended): if you don't know how to dress a screwdriver, you shouldn't be messing around inside your SM300. I'm all for learning basic mechanical skills, but practice on a beater and leave your nice watches to the professionals until you know what you're doing.
     
  6. speedbird Apr 15, 2014

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    Most things are DIY but anything involving a wristwatch, barring bracelet changes , is for a professional
     
  7. VictorAlpha Apr 16, 2014

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    Thank you very much for taking the time to respond to me. Especially Al, I replied to Al via email as I was on the move this morning and failed to see that it was an 'Omega Forum' notification on my mobile. Strangely enough none of the other replies show up as an email! My reply was as follows:

    Hi Al,



    I have removed only two movements so far, one being a quartz. I know there is a risk involved but think that for these small jobs most watchmakers find them too routine to take due care. Let me explain:

    The quick backstory that I didn't mention to try and keep my post to a reasonable length is that I did in fact take it to a reputable experienced watchmaker. I was absolutely horrified that he handled the movement in front of me without using gloves and literally dropped the movement in and out of the case with generally rough and hurried handling. (He wanted to look at it there and then - I was prepared to leave it). He then proceeded to buff the inside of the crystal with an old chamois cloth that was clearly discoloured through grease and oil.
    Once I got back into my car I noticed that the almost invisible smudges had become worse and there were now a myriad of tiny scratch marks.


    I have indeed polished the outside of the crystal using polywatch and a lint free new cloth with good results. I have considered sending it back but the service centre is in another city, and frankly the watchmaker doesn't seem too responsive to queries. We have a real dearth of qualified watchmakers in SA so I don't have many alternative options.

    As to dressing a screwdriver, I have done this freehand for other purposes before. I have experience sharpening tools to a finely polished edge so this wont be a huge challenge in itself. Woodwkr2 thank you for the tutorial!
     
  8. Archer Omega Qualified Watchmaker Apr 16, 2014

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    Please don't paint us all with the same brush. Clearly despite the watchmaker being "reputable" and "experienced" he does not have any passion for the work, or he would not treat the watch in the way you describe.

    Just like any other profession, there are good and bad watchmakers out there. In most countries anyone can call themselves a watchmaker, hang out a sign, and get business. There are so few watchmakers around that pretty much anyone can stay in business for some time, even if they do sub standard work.

    Good luck with the job. Take your time, and think before you act.

    Cheers, Al
     
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  9. woodwkr2 Apr 16, 2014

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    If I were you, I'd recommend going back to the watchmaker with the hurried handling during a low time. He could open up right in front of you, and you could sit there with some Poly watch and take care of the crystal until it was to your satisfaction (while he went back to other work), then he could help you case it back up.

    If you do proceed on your own, you'll find some tweezers invaluable. Brass tweezers will reduce the chances of adding any scratches. You might want to consider a casing cushion, and a squeeze bulb dust blower (like used in photography) as well. Do everything in a clean, relatively dust free environment. And while the movement with dial and hands is sitting there on your work space (hopefully on the casing cushion), cover it with a wine glass or other container to keep the dust out.

    Some Polywatch and a microfiber cloth is likely all you need on the inside of the crystal. Do not remove the crystal from the case unless you have the proper tools to reinstall the crystal. Gently dust off the dial and inside of the crystal again with the blower (careful not to shoot dust into your movement), and go real slow re-seating the dial and movement in the case before flipping over the casing cushion and reinstalling your case clamps.

    I don't know if your watch was previously water resistant, but once you're done it likely will not be.
     
  10. Georgieboy58 Apr 16, 2014

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    IIRC, you get notifications for the direct responses to your entry, or if someone quotes your entry.
    So now you should have 2 more notifications. This behaviour can be influenced in your account settings to some extent.
     
  11. VictorAlpha Apr 16, 2014

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    Thank you for all your responses,

    Al I didn't mean to sound cynical about all watchmakers, I know from the various forums whilst researching my SM300 build that you and some others have an absolutely stellar reputation. I agree with your comment about lack of passion for the job. Its possibly a byproduct in this case at least, of 6 decades of large workloads and overly demanding and nitpicking customers who want everything for free!

    Woodwkr2 thanks for the info. I do have 2 sets brass tweezers, blower, movement and case holders and cushion, polywatch, lint free microfibers and various containers to store the movement case etc in a dust minimal invironment. I also have gasket silicone grease rodico finger cots etc, and have now ordered some high quality screwdrivers, pegwood magnifiers and a screwdriver jig for dressing on a waterstone.

    As advised I plan on going slow. The watch was indeed waterproof. I should be able to get it retested at the local g-shock agents they can apparantly test up to 200m.

    Thank for your suggestions (and cautions).
     
  12. woodwkr2 Apr 16, 2014

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    Well, for someone who has only uncased 2 watches, you certainly sound well equipped.

    Good luck!
     
  13. Spacefruit Prolific Speedmaster Hoarder Apr 16, 2014

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    We all start somewhere.

    in my experience a motivated amateur is far better than a bored, disinterested or otherwise hobbled professional. And in my town, I would not trust a soul with my omegas. (Bangkok).

    dismantling an omega as my first project was too daunting, or at least financially frightening, so I acquired a few battered fakes from the street markets and took them apart......none got back together, but now I am confident on most dismantling as far as case components, and even hand replacement.

    The key is to go very, very slowly. And put to one side jobs that threaten the watch, even if that means waiting three months until I can get out of the country to a real watchmaker.

    Patience, and knowing my limits. That's the key for me.
     
  14. VictorAlpha Apr 17, 2014

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    Thanks Woodwkr2, the equipment I have built up over the last few years as my interest in watches developed. My intention was to do a lot more hobby fettling and learning. Work and other circumstances have left me with little time do do that very much. Now I have just ordered a few more items for this job as I've learned that there is nothing like having the wrong tools to turn a straightforward job into a nightmare.

    Honestly my biggest concern here is making sure the screwdriver blade fits the case clamp screw slot correctly to avoid damaged screws. The little jig should come in handy for that.

    If I get to a point where I'm not comfortable I will package it up and send it off. It seems that it wont be much different then removing the ubiquitous ETA 2824 movement though and protection of the movement hands and dial surfaces while handling and storing will be paramount.

    Thanks again your interactions have been really helpful. The recurring theme seems to be caution, maybe I am being foolhardy If I mess it up I'll only have myself to blame not some other guy with a dirty rag and some dubious watch handling habits.
     
  15. woodwkr2 Apr 17, 2014

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    Your best chance of restoring water resistance is to lightly lubricate the gaskets whenever you have the case opened up. You can get a small gasket oiler for a few bucks (it kind of looks like those foam shoe polish containers). Put your gasket in, close the lid, open and reinstall the gasket.

    Careful not to over do it though! You don't want silicon grease anywhere near your movement. Wipe off any visible excess with a clean Q-Tip or Kim Wipe before you tighten the caseback down.
     
  16. Archer Omega Qualified Watchmaker Apr 17, 2014

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    When someone unknown to us here posts saying they want to remove the movement from the case, and says they can't undo the case clamp screws, that does not inspire a lot of confidence in you doing the job without damaging something.

    If you had said in your first post that you have done this sort of thing before, we may not have told you this was something you shouldn't attempt. This is exactly why I asked if you had ever removed a movement from it's case before.

    Let's just say I have seen a lot of self inflicted carnage by watch owners who don't really know what they are doing, and I end up being the one to fix the damage they do. It's possible to do hundreds of dollars worth of damage very quickly just removing a movement from it's case if say a screwdriver slips, so even though it's not my money, I hate seeing people get upset with what they have done when these mishaps occur.

    Anyway, let us know how it all turns out.

    Cheers, Al
     
  17. VictorAlpha Apr 17, 2014

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    Thanks for the tip re silicone and movement. At the risk of sounding improbably prepared, I do have one of those and used it when I opened the caseback. The gasket although quite hefty as these things go, was completely dry.

    I am not yet sure however how the crown and tube seals appear on this case nor how to access them to lubricate. They are the original stiff seals this case comes with.

    It had apparently passed muster at the service centre's pressure test.
     
  18. woodwkr2 Apr 17, 2014

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    Just lube the caseback gasket. The others are more protected and therefore, less accessible. They can be lubed when a full service/overhaul is performed by the watchmaker.
     
  19. Archer Omega Qualified Watchmaker Apr 17, 2014

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    Be aware the silicone grease does not form the seal - it is only there to prevent the seal from bunching up as the case back is screwed in place. The seals are inside the crown, so you can simply apply some silicone grease to the outside diameter of the case tube before replacing the crown and stem.

    Cheers, Al
     
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  20. woodwkr2 Apr 17, 2014

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    :rolleyes: Learn new tricks every day around here.