timefactors watches



TZ-UK Fundraiser
Results 1 to 8 of 8

Thread: Help Wanted - Changing the crystal on a Seiko SNA029 (7T62-0AH0)

  1. #1

    Help Wanted - Changing the crystal on a Seiko SNA029 (7T62-0AH0)

    I have a newly arrived Seiko SNA029 that would really benefit from a new crystal.

    I can source one from Cousins (looks to be either the 300P30HN02 or the 300P30LN03), but whilst I have replaced plenty of crystals before in "regular" watches I haven't done one in a chronograph.

    Is it something an amateur watch fettler can do, or would it be better sent off to a professional?

    Also is there anything special I need to be aware of, either with a chronograph in general or this model Seiko in particular? Any hints and tips?

  2. #2
    Grand Master
    Join Date
    Jul 2007
    Location
    Wakefield, West Yorkshire
    Posts
    16,158
    Depends whether the crystal is retained by the bezel or not. I have a Seiko with the crystal retained by the bezel, sealing on a rubber O ring. Alternatively, the crystal may simply be a press fit into a nylon gasket. You need to inspect v. carefully to determine which. Iím assuming the watch has a removable bezel, canít be certain from the pics. Careful inspection with a strong magnifier should resolve this.

    Once the glass is out it should be possible to measure it careful and check whether a generic replacement is available. If youíre lucky a sapphire alternative may be available.

    The fact that itís a chrono doesnít matter, itís the construction of the case that you need to work out.

    Donít forget to test for WR, Iíd do this whilst the movementís out. Best to check the new glass has sealed corrctly, you donít want a nasty surprise!

  3. #3
    Many thanks Paul for the very useful information.

    The specification of the crystal was from boley.de, who suggest both this reference (300P30LN03) and an alternative version (300P30HN02). The watch database on Jules Borel just have the 300P30HN02 listed. The latter is no longer stocked, or at least not by Cousins, and I can't find it on any of the normal sites I use. Cousins have the LN03 variant, though.

    For 18 quid I'm inclined just to give it a try, as it is a domed Hardlex crystal that I am not sure would be easily available as a generic. Crystaltimes show a SNA029 on the same page as their sapphire replacement crystal for the RAF issue Gen 1, but as its only shown in passing I have emailed them to see if it is indeed a suitable replacement.

    I have a case-back gasket and also the crystal gasket in the same shopping basket at Cousins, so hopefully if anything is untoward with the current ones I'll have spares.

    The bezel doesn't appear to be (re)movable, and it's not listed as a separate part on either of the sites above, so hopefully the crystal can be replaced with it in situ.

    Rodico - check
    Pegwood - check
    Pointy cotton wool buds - great suggestion and added to basket

    Thank you again.
    Last edited by willie_gunn; 17th September 2018 at 20:19.

  4. #4
    Crystaltimes have emailed me back and assured me that their CT052 sapphire replacement will fit, so one is ordered and is soon to be on its way. Itís flat, rather than domed.


    Sent from my iPad using TZ-UK mobile app

  5. #5
    Apprentice
    Join Date
    Sep 2018
    Location
    London
    Posts
    9
    Yes. Thanks Paul.

    Quote Originally Posted by willie_gunn View Post
    Many thanks Paul for the very useful information.

    The specification of the crystal was from boley.de, who suggest both this reference (300P30LN03) and an alternative version (300P30HN02). The watch database on Jules Borel just have the 300P30HN02 listed. The latter is no longer stocked, or at least not by Cousins, and I can't find it on any of the normal sites I use. Cousins have the LN03 variant, though.

    For 18 quid I'm inclined just to give it a try, as it is a domed Hardlex crystal that I am not sure would be easily available as a generic. Crystaltimes show a SNA029 on the same page as their sapphire replacement crystal for the RAF issue Gen 1, but as its only shown in passing I have emailed them to see if it is indeed a suitable replacement.

    I have a case-back gasket and also the crystal gasket in the same shopping basket at Cousins, so hopefully if anything is untoward with the current ones I'll have spares.

    The bezel doesn't appear to be (re)movable, and it's not listed as a separate part on either of the sites above, so hopefully the crystal can be replaced with it in situ.

    Rodico - check
    Pegwood - check
    Pointy cotton wool buds - great suggestion and added to basket

    Thank you again.

  6. #6
    The sapphire replacement turned up from CrystalTimes last week and I took the opportunity on Sunday to replace the existing mineral glass in the watch.

    It was all pretty straightforward.

    The result is excellent in terms of legibility. My only slight niggle would be that another couple of thou' in terms of the glass thickness would be useful. As it is, there is a "lip" between the glass and the bezel, though the glass being below the bezel hopefully means that it may be better protected.



    I love the second time zone feature, in many ways preferring it to the normal "second hour hand" seen on many GMT's.

  7. #7
    Grand Master
    Join Date
    Jul 2007
    Location
    Wakefield, West Yorkshire
    Posts
    16,158
    Looks good to me, a job well done!

  8. #8
    Quote Originally Posted by walkerwek1958 View Post
    Looks good to me, a job well done!
    Thank you Paul.

    Itís kept good time all week and looks a lot sharper to boot!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •