Inline FabricationReloading EverythingPBcastcoWideners
Titan ReloadingRotoMetals2MidSouth Shooters SupplyLee Precision
Repackbox Load Data
Page 1 of 2 12 LastLast
Results 1 to 20 of 29

Thread: Thread size Odd ball-ium

  1. #1
    Banned
    Join Date
    Feb 2016
    Posts
    2,725

    Thread size Odd ball-ium

    I guess there is always something new to learn.
    I have learned a lot buying odd ball stuff on eBay for super cheap.
    Did it again.
    This is it.....
    1/8-40 thread grub screws.
    I had never heard of such a thing. I thought "it must be a typo or Chinese to English confusion". So I figured "it's gotta be actually 8-40 threads like the standard scope mount screws we are all familiar with. Around a buck for a package of 20 screws so I pop for it...Turns out they ACTUALLY ARE 1/8-40 screws. Are you kidding me? Spent a half hour trying to research such an odd ball size. NOTHING. So I go back to eBay and look for more screws, taps and such (now I need a 1/8-40 tap)
    Turns out for you folks "across the pond" who are laughing now...It is BRITISH STANDARD THREADS.
    I don't know if they use it much anymore, but, sure enough there it is.
    NOW, because of the price of this stuff... Less than $2.00 for a tap (I ordered 3 of em) and a little over a dime a piece for all kinds of various length cap screws...I am now a happy user of BRITISH STANDARD THREAD SIZE 1/8-40.
    By the way it is just a tiny bit bigger than 6-40 which is actually a nice fit for a lot of stuff that I do. But I pity the person who tries to work on the stuff I make with these....I might have to include a note on everything warning them of this ODDBALLIUM.

  2. #2
    Moderator


    Winger Ed.'s Avatar
    Join Date
    May 2007
    Location
    Just outside Gun Barrel City, Texas
    Posts
    9,430
    I had fits with nuts & bolts when I had a Triumph and MG.

    Bolts looked the same as American ones, but the shape of the threads were different. Rounded instead of a sharp 'V'.

    Sometimes it took a 'extension' on a ratchet handle to snug 'em up.
    Last edited by Winger Ed.; 01-23-2020 at 07:41 PM.
    In school: We learn lessons, and are given tests.
    In life: We are given tests, and learn lessons.


    OK People. Enough of this idle chit-chat.
    This ain't your Grandma's sewing circle.
    EVERYONE!
    Back to your oars. The Captain wants to waterski.

  3. #3
    Boolit Master
    Join Date
    Dec 2016
    Posts
    1,089
    Also known as British Standard Whitworth, or B.S.W.

  4. #4
    Banned
    Join Date
    Feb 2016
    Posts
    2,725
    Quote Originally Posted by Gewehr-Guy View Post
    Also known as British Standard Whitworth, or B.S.W.
    Oh, I have heard of Whitworth... Lot's of old tooling is in that standard. Didn't know the full name was British Standard Whitworth. Must be the standard before they went to metric.
    Thanks for that.

  5. #5
    Boolit Master
    Join Date
    Jul 2014
    Location
    Arizona
    Posts
    4,593
    I had similar issues with bolt sizing when I restored a 56 BSA motorcycle back in the 70s.
    Wanted to keep it stock , so a three month project ended up taking a year.

  6. #6
    Boolit Buddy
    Join Date
    Feb 2010
    Location
    northeastern washington
    Posts
    353
    Machinery's handbook is your friend. Lists most threads used in the past 100+ years in US types, British, European and Metric. Many odd pitch sizes that were used in old guns and machines before WW2 [proprietary] that are one side +/- of standard NC/NF. Like 1/4-18 or 1/4-32
    Shaune509

  7. #7
    Boolit Master

    Join Date
    Feb 2007
    Location
    Lewiston, Idaho
    Posts
    2,724
    1/8-40 is a standard size, sometimes it is listed as a machine screw size 5-40. I have taps with these markings. First time I saw this size was for axles on slot cars over 50 years ago.

  8. #8
    Boolit Master
    Join Date
    Nov 2017
    Location
    brisbane ,qld,australia
    Posts
    2,110
    1/8 x40 was a very common thread in electrical appliances in the days when they actually had sheet metal frames and chassis...1/8 Whit.Also used in at least one military gun Im aware of...British car and bike electrics used the BA threads,which are actually metric in origin......British bikes used many 26tpi based threads,BSC and many specials....Pre 67 Jap metric threads can also be different to standard metrics.

  9. #9
    Boolit Master
    Join Date
    Sep 2016
    Posts
    2,377
    And to add to the list of British threads is the model engineering threads which I believe were all 40 threads to the inch. Used to have a bunch of British model making magazines.Steam engines both stationary and fully operable steam locomotives,steam powered boats both small and large. And my personal favorite was the flash steam model boats. Frank

  10. #10
    Boolit Master

    merlin101's Avatar
    Join Date
    Mar 2010
    Location
    Rochester NY heading to Gaults Gulch
    Posts
    1,303
    I still have some old Whitworth wrenches in my tool box, my favorite is the 1/2 Whit.
    It's not the years in your life that count. It's the life in your years (Abe Lincoln)

    "A free people ought not only to be armed and disciplined, but they should have sufficient arms and ammunition to maintain a status of independence from any who might attempt to abuse them, which would include their own government.” George Washington

  11. #11
    Boolit Master
    Join Date
    Jan 2016
    Posts
    990
    GONRA sez watchout for 55 degree thread form. Not the 60 degree we are all used to!!!
    From Memory: Luger pistol Barrel barrel threads are 55 degree Whitworth - 20 / inch.

  12. #12
    Boolit Master
    Join Date
    May 2017
    Posts
    3,683
    Quote Originally Posted by GONRA View Post
    GONRA sez watchout for 55 degree thread form. Not the 60 degree we are all used to!!!
    From Memory: Luger pistol Barrel barrel threads are 55 degree Whitworth - 20 / inch.
    On machinery you will get away with the 55 vs 60 degree but its easy to get used to the idea that Whitworth is the same TPI as National coarse - they are - all except for the most popular size (half inch) where whitworth is 12TPI and NC is 13TPI ---- so with a good fitting spanner and a long handle you will get it almost a nut depth before something is boogered -spare a thought for Aussies - we got the lot to deal with - BSW/SAE/NF/NC/Metric- then a kids bike was all 26TPI no matter the diameter along with a lot of early pommy motors and such - IH tractors from the 1980's had National fine /coarse threads on the motor and transmission and metric for the running gear and body work. Tis what we get when Bureaucrats start to mess with things.

  13. #13
    Banned
    Join Date
    Feb 2016
    Posts
    2,725
    It took a little shaking for things to settle out to Unified Thread Standard and Metric. Some folks want to get rid of Unified thread standard and just have metric.
    To that I say N O W A Y. People are lazy and stupid enough nowadays. Those different standards keep a person on their toes.
    Last edited by Traffer; 01-26-2020 at 07:04 PM.

  14. #14
    Banned
    Join Date
    Nov 2012
    Location
    Central Virginia
    Posts
    7,439
    Quote Originally Posted by merlin101 View Post
    I still have some old Whitworth wrenches in my tool box, my favorite is the 1/2 Whit.
    I see what you did there

  15. #15
    Banned
    Join Date
    Nov 2012
    Location
    Central Virginia
    Posts
    7,439
    I don't mind vehicles with English fasteners or metric ones, it is when they mix them up on the same vehicle that I get a bit perturbed.

    Speaking of mildly perturbed, (that's the British equivalent of enraged here in America) you haven't learned to cuss until you work on an old British car with rusted Whitworth fasteners that aren't quite Whitworth dimensions anymore, steel that is somehow capable of being thick & heavy but still weak and rust prone (I'm not sure how the Brits figured out that metallurgic combination) and Lucas electrics.

  16. #16
    Boolit Master

    Join Date
    Feb 2007
    Location
    Lewiston, Idaho
    Posts
    2,724
    I understand they drink their beer worm over there, seems Lucas made refrigerators also.

  17. #17
    Banned
    Join Date
    Feb 2016
    Posts
    2,725
    Quote Originally Posted by Petrol & Powder View Post
    I see what you did there
    Thanks, It went right over my head...now I see the light.

  18. #18
    Banned
    Join Date
    Feb 2016
    Posts
    2,725
    Quote Originally Posted by John Taylor View Post
    I understand they drink their beer worm over there, seems Lucas made refrigerators also.
    What is a Beer Worm? I'm not drinking any Brit beer NOW.

  19. #19
    Boolit Master Bad Ass Wallace's Avatar
    Join Date
    May 2005
    Location
    Australia
    Posts
    1,956
    Had troubles with another British thread " Enfield Inch". My lathe cuts 36,38,40 tpi but this thread was 37TPI

    I managed to get a thread die from a little shop in England and now turn the body in the lathe and thread with the die.
    Hold Still Varmint; while I plugs Yer!

  20. #20
    Boolit Buddy
    Join Date
    Mar 2017
    Posts
    192
    Quote Originally Posted by John Taylor View Post
    seems Lucas made refrigerators also.
    Lucas is the Prince of Darkness

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check