Page 1 of 2 12 LastLast
Results 1 to 15 of 24
  1. #1
    Join Date
    Apr 2012
    Location
    Whitby, UK
    Posts
    17

    Default Extra coarse bolt thread?

    I require a very small machine screw as a replacement for one that has fallen out of a Shimano fishing reel. It seems to be a very coarse thread, more so than UNC or metric coarse. The maximum diameter across the tips of the threads is 1.92mm and a 6mm long screw out of the same reel has 14 threads (+/- 56 TPI). As far as I know M2 coarse and UNC of a similar size have 63 TPI. Just wondering if anyone has any idea what thread size I need (1.92mm/56TPI) or could it be custom made for Shimano.

    Thanks

    Mike

  2. #2
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,440

    Default

    Hi Mike,

    Could it be 9BA, that is 1.9 mm 64.9 tpi. I can't find anything around 56 tpi of that diameter,
    Best Regards:
    Baron J.

  3. #3
    Join Date
    Oct 2011
    Location
    Norwood-ish, Adelaide
    Age
    59
    Posts
    6,541

    Default

    If it is a Shimano fishing reel, it is Japanese so probably their version of metric. You need to be looking at JIS thead tables.

    Michael

  4. #4
    Join Date
    Feb 2013
    Location
    Laidley, SE Qld
    Posts
    1,038

    Default

    Bear in mind that manufacturers can and do make whatever size/thread fixings that best suit the application. They usually follow the thread charts but not always. A Japanese screw with an OD of 1.92mm suggests a 2mm nominal OD.

  5. #5
    Join Date
    Nov 2007
    Location
    melbourne australia
    Posts
    3,228

    Default

    Quote Originally Posted by mikex View Post
    a 6mm long screw out of the same reel has 14 threads (+/- 56 TPI). As far as I know M2 coarse and UNC of a similar size have 63 TPI.
    M2 has a pitch of 0.4mm. Assuming it IS a M2 screw, 14 threads would be 5.6mm long. A combination of small errors in length measurement and pitch count would account for the difference (your 6mm screw is unlikely to have exactly 14 threads on it). I'd be trying a M2 first.
    Chris

  6. #6
    Join Date
    Jun 2007
    Location
    sydney ( st marys )
    Age
    64
    Posts
    4,887

    Default

    Can you buy one as a spare part?

  7. #7
    Join Date
    Dec 2007
    Location
    Adelaide
    Posts
    574

    Default

    M2.2 coarse is approx 56TPI

  8. #8
    BobL is offline Member: Blue and white apron brigade
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    7,183

    Default

    i'd like to see a close up photo of it laying on a ruler with mm markings on it.

  9. #9
    Join Date
    Nov 2007
    Location
    melbourne australia
    Posts
    3,228

    Default

    Quote Originally Posted by familyguy View Post
    M2.2 coarse is approx 56TPI
    But the screw is 1.92mm OD.
    Chris

  10. #10
    Join Date
    Jun 2007
    Location
    sydney ( st marys )
    Age
    64
    Posts
    4,887

    Default

    Probably just file it down to suit, be a good exercise in filing round and debuting small threads.

  11. #11
    Join Date
    Mar 2011
    Location
    Southern Flinders Ranges
    Posts
    1,536

    Default

    I feel like I’m missing something here, why are metric thread threads being quantified in threads per inch?

  12. #12
    Join Date
    Oct 2004
    Location
    Southern Highlands NSW
    Posts
    1,894

    Default

    Some 56 tpi in small diameters on the attached list.
    Attached Files Attached Files

  13. #13
    Join Date
    Dec 2007
    Location
    Adelaide
    Posts
    574

    Default

    Quote Originally Posted by racingtadpole View Post
    I feel like I’m missing something here, why are metric thread threads being quantified in threads per inch?
    I think because the OP mentioned TPI rather than pitch - many comprehensive thread charts have both pitch and TPI so it is easy to quote either.

  14. #14
    Join Date
    Dec 2018
    Location
    NSW
    Posts
    586

    Default

    Quote Originally Posted by familyguy View Post
    I think because the OP mentioned TPI rather than pitch - many comprehensive thread charts have both pitch and TPI so it is easy to quote either.
    Why use metric when you could use FREEDOM UNITS!!!

    ...Actually, no, F that.

  15. #15
    Join Date
    Nov 2009
    Location
    australia
    Posts
    57

    Default

    Think you better go buy a couple of sets of these, buy one set Metric, the other set Imperial !!!!

    That way YOU will be able to identify the thread correctly and then YOU will know what your talking about.
    Others will then be able to advise correctly, without taking a stab in the dark.


    https://www.ebay.com.au/itm/Measurin...AAAOSwyO1awxhg

Page 1 of 2 12 LastLast

Similar Threads

  1. Extend thread on a socket head bolt
    By justask4 in forum METALWORK GENERAL
    Replies: 22
    Last Post: 31st Oct 2019, 10:49 PM
  2. Cutting a coarse left hand thread.
    By Boringgeoff in forum METALWORK GENERAL
    Replies: 52
    Last Post: 12th Sep 2019, 10:23 AM
  3. Imperial and Metric Bolt Thread and Torque Chart
    By moorebrm in forum METALWORK GENERAL
    Replies: 5
    Last Post: 31st May 2016, 01:48 AM
  4. 1" BSP as a nut & bolt thread.
    By bob ward in forum METALWORK GENERAL
    Replies: 2
    Last Post: 22nd Jul 2014, 03:29 PM
  5. american thread bolt 8-32 where?
    By old_picker in forum METALWORK GENERAL
    Replies: 6
    Last Post: 6th Aug 2011, 06:47 PM

Posting Permissions

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