1. The Forum Rules have undergone some minor changes and updates.  Please take the time to read them; it will only take a couple of minutes of your time. By doing so, you lessen the chance of incurring the wrath of the moderation team or making yourself look foolish to other members.

    90% of users posting adverts in the Sales forums need to be reminded to read the rules as their posts are wrong.  This is unnecessarily time-consuming and will no longer happen - if your advert doesn't follow the Sales Rules it will be deleted and you'll have to start all over again.

    To close this box once you've read it (and the Rules), click on the X in the top right-hand corner.

    Thank you.

    AGF Staff



    Dismiss Notice
  2. A reminder of one of the Forum Rules:

    'Behaviour

    Do not make inappropriate or offensive posts - including threats, harassment, swearing, prejudice, defamation, deliberate insults or name-calling, other negative remarks about this forum, its moderators and administrators or your fellow members. Even if this is just your own personal opinion, RESPECT YOUR FELLOW MEMBERS.'

    There have been changes made to our censoring software in an attempt to help with this growing problem.

    Click the X in the top-right-hand corner to dismiss this notice.
    Dismiss Notice
  3. Dear members,

    Our membership (like our country) consists of people from all walks of life; different in far more ways than can be listed here and each with a different view based on their experience of life - regardless of their colour, religion or cultural heritage. Every single person in the UK has been born of mixed race – we are a multi-coloured and multi-cultural country.

    As many of you are aware there are a handful of individuals amongst this membership that persist in making provocative, inflammatory, racist and otherwise offensive comments. This has been happening across the forum to a certain degree but is most especially prevalent in the Adult section.

    The moderation team has tried to stay on top of this, however unfortunately because of the ‘offensive’ nature of much of its content we don’t monitor the Adult section quite as much as perhaps we should. As a result much of this behaviour has gone unnoticed unless it has been reported to us. While the team always intended to take a "light touch" approach to the Adult section it would seem that some people aren’t quite adult enough to be left unmonitored after all.

    This behaviour is, and always has been against Forum Rules as well as the specific stipulations of the Adults forum and it will no longer be tolerated. We feel it's time to draw a line in the sand and as such from this point onward offenders will receive an immediate and permanent ban from the forum.

    In order for us to achieve our goal of restoring the forum to the friendly and tolerant place it once was, we ask that ALL members be mindful of the content they post and help us to stop unacceptable behaviour by using the 'Report' tool at the bottom of any offending post - the results of which can be seen only by Admin/Moderators.

    You should all receive a copy of this message by PM. 

    To close this message box, click on the 'X' in the top-right-hand corner.

    Dismiss Notice
  4. Hotmail block emails from us entering your inbox. Unless you can setup a safe sender you will not get activation emails from the forum. Please use an alternative provider or complain to Hotmail.
    Hotmail addresses include.

    @Hotmail.co.uk @Hotmail.com @outlook.com @Live.com
    Dismiss Notice
  5. Postings on Politics, Religion & Controversial Off-Topic Material

    The majority of users do not want to read about these subjects and people have left the forum as a result of it – this is after all an 'Airgun' Forum. It’s all very well to say they don’t have to read it if they don't want to, but as most of us use the ‘New Posts’ button there is no easy way to avoid it.

    All AGF staff members are in favour of people being able to discuss what they want, but we have to draw the line somewhere if it is upsetting other users. We don’t want to read about these topics either.

    IMPORTANT- The discussion of politics and religion is no longer allowed anywhere on the forum (including the Adult section).  The only exception is if it's airgun related - they must be put in the Airgun Related Politics section..

    We will not tolerate bullying or personal attacks, racism or any other offensive 'isms'. we will remove these topics from the forum, we will not give you an area where you can abuse each other. We will not hesitate to ban offenders.

    To clear this text box, click on the 'X' in the top right-hand corner.

    Dismiss Notice

Anyone Got Access To A Toolmakers Microscope

Discussion in 'Technical' started by Radlad, Oct 11, 2019 at 10:16 AM.

  1. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    Help please. does anyone have access to one and can identify a Webley threaded screw for me?

    The screw is the trigger adjusting screw for the pre war pistols. It appears to be a special as I've checked every thread table I can find going back to the 1880s and the equipment I have at home (and my eyesight) is not sufficient to identify it. A guess is 5/32" x 52 tpi but that isn't an accurate one. Pitch and thread angle is what I need to know and I have a sample screw to measure but need to make a couple more. Can't make a tap to make a die until I know.

    PLEEEEEEEEEASE??????????????
     
  2. TrickyDicky

    TrickyDicky Life in the slow lane

    Messages:
    2,994
    Likes Received:
    3,068
    Location:
    Kings Lynn
    Have you thought about one of those cheap USB microscopes from ebay they work quite well.
     
    Radlad likes this.
  3. Mike6J

    Mike6J Well-Known Member

    Messages:
    65
    Likes Received:
    66
    Location:
    Wessex
    I am a timeserved toolmaker and have never heard of a toolmakers microscope.
    We used jewellers loops to read verniers, and an unknown thread was gauged.
    Microscopes were fitted to Wickman Optical Profile Grinders but they were rare machines even in top level tool rooms. When I was trained by Wickmans there were less than 50 nationally.

    The thread will probably be British Association (BA) or Unified National Fine (UNF).
    Measure the Outside Diameter (OD) and the teeth per inch (TPI) accurately or use thread gauges.

    I have some original 50's Webley screws and bolts around somewhere and will check them if you cannot guage the thread yourself.

    Keep us informed.
     
    Redcap 114 and cloverleaf like this.
  4. NorfolkDave

    NorfolkDave Donator

    Messages:
    2,645
    Likes Received:
    1,006
    Location:
    Norwich
    I think he needs the measuring facility that a toolmakers scope has.

    Dave
     
    Radlad likes this.
  5. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    Yes, thanks. It's not something I would use that often but a toolmakers microscope is a specialised piece of kit that can measure thread angles accurately. Something that a normal microscope system won't do. TPI can be counted under high magnification but not much else .
    If needs be I will buy something like the USB ones because I'm coming across a lot of b*****d sized screws now I'm working on older airguns. This one , being a very fine, shallow thread, is causing me particular problems.
     
  6. NorfolkDave

    NorfolkDave Donator

    Messages:
    2,645
    Likes Received:
    1,006
    Location:
    Norwich
    If there's a standards room anywhere near you, they may have a shadowgraph you could borrow for a few minutes.

    Not much in fashion these days but very handy for obscure threads.

    Dave
     
    Radlad likes this.
  7. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    Thread is no known range, estimate TPI to be about 52. no thread gauge will go near it ( I have a good assortment) . Not a cat in hells chance it is a common one. I have even checked the Enfield and Holtz tables and all obsolete thread tables I can find.
     
  8. Chandelier man

    Chandelier man Keyboard Hero

    Messages:
    2,053
    Likes Received:
    1,786
    Location:
    Southend on sea
    I have a magnifying glass on my iPhone and it is brilliant :up: my eyesight it terrible for close up even with glasses but the magnifying glass gets me out of trouble ... I use it to see inside my hearing aid filter which is only about 2mm wide
     
  9. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    That would be perfect, but I don't know of any:( But you have just given me an idea. I have an old film projector that I might be able to adapt a slide holder for.

    Thank you, I would like your post a hundred times but the site only lets me do it once
     
    Last edited: Oct 11, 2019 at 11:11 AM
    Crash one likes this.
  10. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    Tried my 10x jewellers loupe, no good. 2mm is a mountain compared to this thread think less than .5 of a mil across and possibly .25 deep. I need to accurately measure angles across that size
     
  11. Scrinja

    Scrinja Trust Me

    Messages:
    530
    Likes Received:
    713
    Location:
    Sierra Blanca Marbella
    Radlad likes this.
  12. NorfolkDave

    NorfolkDave Donator

    Messages:
    2,645
    Likes Received:
    1,006
    Location:
    Norwich
    Nay problem, my background was related to metrology. Knew it would come in handy one day.

    Dave
     
  13. Ed Enticknap

    Ed Enticknap Newbie

    Messages:
    1
    Likes Received:
    1
    I think the tool you would need to identify size of pitch of thread would be a shadowgraph projector, most toolmakers workshops will have them.
     
    Radlad likes this.
  14. Mike6J

    Mike6J Well-Known Member

    Messages:
    65
    Likes Received:
    66
    Location:
    Wessex
    One of my old Webley gun screws is certainly 52-3 TPI but its OD .187" (3/16")

    Would you like me to check the thread against my BA gauges and taps?

    I have three such screws of two different patterns.
    No chance any have worn as they are unused.
     
    Radlad likes this.
  15. HW100Tuning

    HW100Tuning Straight Pride

    Messages:
    2,477
    Likes Received:
    2,872
    Location:
    Notts UK
  16. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    My 5/32" measurement was actually an approximation. The actual major diameter averaged over 3 screws is 0.14615" . I have Ba Taps, Dies and gauges from 1-16. It equates to nothing listed on any thread table I can find from when standardisation started in about 1880 to date. I think it is a thread peculiar to Webley very much in the vein of the Enfield thread series used by the RSAF.
    Thanks for looking anyway
     
  17. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    I have over 20 thread gauges , some for thread series you will probably not have heard of. My 10x magnification jewellers loupe is useless on this thread. I think ( am pretty certain) , it's peculiar to Webley

    It is such a fine thread that it needs specialist equipment to identify ( Thread angle, root and crest shape, pitch, minor diameter etc) and I can't make the tools to replicate it until I know exactly what it is.
     
  18. HW100Tuning

    HW100Tuning Straight Pride

    Messages:
    2,477
    Likes Received:
    2,872
    Location:
    Notts UK
    Post a pic of the thread next to a steel rule.

    To be honest when I have had a bolt (male) and a female version of the thread I have always found them easy to replicate. Find the pitch, thread angle and major diameter. Then stick it in the cnc with a minor thread depth of bigger than needed, then just keep running the machine taking of a little more from the minor on every run and then checking to see if it fits the female.

    Is it a big diameter thread?
     
    Last edited: Oct 11, 2019 at 6:39 PM
  19. Radlad

    Radlad Engaging Member

    Messages:
    190
    Likes Received:
    182
    Location:
    Rossendale
    I've had it against a Micro comparator. Against a steel rule it just looks smooth. vaguely discernible as a thread. A magnification of 100 might show some detail but I can't photograph to that standard with the kit I've got. I need far more accurate detail than just pitch.

    A thread Microscope or, as others have stated, a shadowgraph machine is what's needed.
     
  20. HW100Tuning

    HW100Tuning Straight Pride

    Messages:
    2,477
    Likes Received:
    2,872
    Location:
    Notts UK
    and this thread is on a Webley?

    :worthless:
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice