Lathe Thread Cutting
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 38
  1. #1
    Join Date
    Dec 2018
    Country
    AUSTRALIA
    Posts
    15
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    3

    Default Lathe Thread Cutting

    My lathe (Eriksen 180-NE) will cut 63 Standard Whitworth, 54 Metric and 40 Module thread types. I believe the 'module threads' means worm gears but am not sure.

    Will this machine do Imperial threads? I may be using poor terminology here but I mean the standard threads that our USA cousins use. Generally in Australia we use metric but I am thinking ahead if I ever need to repair other thread types. My current understanding is that UNF is the same as Whitworth fine but that UNC is different to Whitworth course. That means I can potentially do UNF but not UNC.

    Am I right?

  2. #2
    Join Date
    Sep 2010
    Location
    Victoria Australia
    Posts
    3,638
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1426

    Default

    Quote Originally Posted by Mk1_Oz View Post
    My lathe (Eriksen 180-NE) will cut 63 Standard Whitworth, 54 Metric and 40 Module thread types. I believe the 'module threads' means worm gears but am not sure.

    Will this machine do Imperial threads? I may be using poor terminology here but I mean the standard threads that our USA cousins use. Generally in Australia we use metric but I am thinking ahead if I ever need to repair other thread types. My current understanding is that UNF is the same as Whitworth fine but that UNC is different to Whitworth course. That means I can potentially do UNF but not UNC.

    Am I right?
    Hello Mk1_Oz,
    Not really. The basic difference between a UN and Whitworth threads is the included angle of the Thread Form; they both have Imperial Leads. Accordingly, any of the Imperial Threads you mentioned can be cut if the Quick Change Thread Lead Gearbox supports the Lead of the Thread. Any that aren't supported can be cut by using different change gears in the gear train. This requires a calculation, but its not difficult.

    A machine that is deemed to be Imperial, ie. with an Imperial Lead Screw, will normally have an Imperial to Metric Translation gear having 127 teeth brought into play to cut Metric Lead Thread.

    Regards,

    Bill

  3. Likes Terry Z liked this post
  4. #3
    Join Date
    Mar 2012
    Location
    Geilenkirchen, Germany
    Posts
    2,282
    Post Thanks / Like
    Likes (Given)
    1379
    Likes (Received)
    1164

    Default

    Mk1_oz,
    I think you need to spend some time reading about threads. I get the impression you don't understand. It is important to use the correct terminology as well. If you do not have access to the Machinist's handbook, it is highly advisable to get one. No machinist should be without one. One of the many specifications of any thread is the pitch or lead. This is expressed several ways like "Threads per Inch"(TPI) and "Pitch or Lead" this being the distance traveled in one revolution and it can be legally expressed that way in both Metric , Imperial and the British systems. It is this distance we are changing by switching gears on a lathe. The thread profile is another spec and there are many, not just the common 60 and 55 degree form. This form is created by the cutting tool. There is of course much more. On this subject, Google is your friend.

  5. Likes tdmidget, fusker liked this post
  6. #4
    Join Date
    Apr 2006
    Location
    Manchester, England
    Posts
    8,034
    Post Thanks / Like
    Likes (Given)
    1127
    Likes (Received)
    5031

    Default

    " Whitworth Fine " ? Do you mean BSF ?

    Regards Tyrone.

  7. #5
    Join Date
    May 2005
    Location
    AZ
    Posts
    2,326
    Post Thanks / Like
    Likes (Given)
    212
    Likes (Received)
    789

    Default

    Quote Originally Posted by steve-l View Post
    Mk1_oz,
    ...It is important to use the correct terminology as well. If you do not have access to the Machinist's handbook,
    I assume the reference is to "Machinery's Handbook". I agree that no machinist (or mechanical engineer or technician), should be without one.

  8. #6
    Join Date
    Aug 2015
    Country
    UNITED STATES
    State/Province
    Illinois
    Posts
    1,330
    Post Thanks / Like
    Likes (Given)
    956
    Likes (Received)
    564

    Default

    You can UNC or UNF threads. Whitworth threads and BSF threads are specified in threads per inch. As long as you set the correct TPI the lathe doesen't know or care if your tool is ground 55* or 60*.

  9. Likes litlerob1, eaglemike liked this post
  10. #7
    Join Date
    Apr 2004
    Location
    Modesto, CA USA
    Posts
    6,661
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1095

    Default

    There are also acme and buttress thread forms for heavy load and big diameter threads. Imperial and American threads are normally described in threads per inch. Metric is commonly described as so many mm between thread crests.
    Bill D.

  11. Likes eaglemike liked this post
  12. #8
    Join Date
    Nov 2013
    Country
    UNITED STATES
    State/Province
    Utah
    Posts
    4,297
    Post Thanks / Like
    Likes (Given)
    1158
    Likes (Received)
    2340

    Default

    Quote Originally Posted by specfab View Post
    I assume the reference is to "Machinery's Handbook". I agree that no machinist (or mechanical engineer or technician), should be without one.
    They're perfect for coffee mug coasters. I have an old one (9th edition) and a new one (25th edition), honestly as a Michinast it's nearly useless in 2018. JMO

    R

  13. #9
    Join Date
    Dec 2012
    Country
    AUSTRALIA
    Posts
    1,787
    Post Thanks / Like
    Likes (Given)
    8
    Likes (Received)
    541

    Default

    When newbies start asking strange questions about Whit threads.....they are often unaware of the whole idea of British Standard. Cycle/Cycle Engineers Institute threads/These are a range of threads ,some fine ,some not, used in bicycles and motorcycles up until about 1975..........and not mentioned anywhere in those 2,500 odd pages.

  14. #10
    Join Date
    Aug 2011
    Country
    UNITED STATES
    State/Province
    Oregon
    Posts
    2,512
    Post Thanks / Like
    Likes (Given)
    550
    Likes (Received)
    752

    Default

    Reminds me of a friend who is restoring an 1850's American lathe, he said no two threads have been alike. Whitworth was well into standardizing his BSW threads by then but I guess it hadn't made it across the Atlantic yet.

  15. #11
    Join Date
    Dec 2018
    Country
    AUSTRALIA
    Posts
    15
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    3

    Default

    Quote Originally Posted by Illinoyance View Post
    You can UNC or UNF threads. Whitworth threads and BSF threads are specified in threads per inch. As long as you set the correct TPI the lathe doesen't know or care if your tool is ground 55* or 60*.
    Ahh that is the answer I was asking for! Yes I aware of the differences in profile having done substantial Google research prior to asking.

    Appreciate all the answers. I am trying to find a copy of a machinist's handbook. If anybody has any suggestions (author, new vs old etc) they would be appreciated.

    Mine is a metric lathe btw.

    Yes I meant BSF rather than Whitworth fine but I was under the understanding that one came from the other. Being part of the old Empire I believe Australia has more uses for the Whitworth stuff than the US.

  16. Likes Mike C., StinkyDan liked this post
  17. #12
    Join Date
    Mar 2012
    Location
    Geilenkirchen, Germany
    Posts
    2,282
    Post Thanks / Like
    Likes (Given)
    1379
    Likes (Received)
    1164

    Default

    Quote Originally Posted by Mk1_Oz View Post
    Ahh that is the answer I was asking for! Yes I aware of the differences in profile having done substantial Google research prior to asking.

    Appreciate all the answers. I am trying to find a copy of a machinist's handbook. If anybody has any suggestions (author, new vs old etc) they would be appreciated.

    Mine is a metric lathe btw.

    Yes I meant BSF rather than Whitworth fine but I was under the understanding that one came from the other. Being part of the old Empire I believe Australia has more uses for the Whitworth stuff than the US.
    You have much more reading to do. These Machinist handbooks are not inexpensive. They come in print and digital DVD form. I have both. I find the digital form very handy because it is searchable.

    Almost nobody anywhere still uses Whitworth......either in England or Australia. However, the 55 degree thread form is far from dead. It is still extensively used in British Standard Pipe fittings both parallel and tapered.

    I am assuming you have never single pointed a thread on your lathe. If so, be advised that because your lathe lead screw is metric, you cannot disengage the half nuts until the thread is complete with inch threads.

  18. #13
    Join Date
    Apr 2015
    Country
    AUSTRALIA
    Posts
    564
    Post Thanks / Like
    Likes (Given)
    33
    Likes (Received)
    134

    Default

    agree whitworth is rarely used now, however UNC, UNF is still commonly used as we import and use many american made components and machinery.
    Although people in the trades now in australia are taught metric as we are officially metric now a lot of industry still works in imperial units so you have to know both.
    machinery's handbook can be found by a simple internet search.

  19. #14
    Join Date
    Apr 2012
    Location
    New Zealand
    Posts
    657
    Post Thanks / Like
    Likes (Given)
    160
    Likes (Received)
    188

    Default

    Quote Originally Posted by litlerob1 View Post
    They're perfect for coffee mug coasters. I have an old one (9th edition) and a new one (25th edition), honestly as a Michinast it's nearly useless in 2018. JMO

    R
    "Zeus" tables seems to be more common in this part of the world- a slim pocketbook with coated leaves, all the thread systems in modern use, durable and universally useful.

    There are a few pitch differences between Whitworth, BSF and UNF/UNC but the theory is the same.

  20. Likes camscan liked this post
  21. #15
    Join Date
    Mar 2012
    Location
    Geilenkirchen, Germany
    Posts
    2,282
    Post Thanks / Like
    Likes (Given)
    1379
    Likes (Received)
    1164

    Default

    Quote Originally Posted by Greenwud View Post
    "Zeus" tables seems to be more common in this part of the world- a slim pocketbook with coated leaves, all the thread systems in modern use, durable and universally useful.

    There are a few pitch differences between Whitworth, BSF and UNF/UNC but the theory is the same.
    There is no comparison between the machinery handbook and any slim pocketbook. The Machinery handbook has been in print for more than 100 yrs. My current edition is the 30th and there is a later one. It is just short of 3,000 pages in really, really small print. Jus sayin

  22. #16
    Join Date
    May 2012
    Location
    Pittsford, NY
    Posts
    1,003
    Post Thanks / Like
    Likes (Given)
    696
    Likes (Received)
    653

    Default

    As a manual machinist, you don't need the most recent Machinery's Handbook. My brother-in-law just picked up a 20th edition at a flea market for $8. It has all the thread data that any edition will have. Amazon.com.au doesn't show anything at a reasonable price, but the US site has the 23rd edition for $12.24. It would be fine for you. Just make sure that you don't accidentally get the "companion" or "guide". These are books that tell you how to use the book...

  23. Likes NRDock liked this post
  24. #17
    Join Date
    Jan 2015
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    111
    Post Thanks / Like
    Likes (Given)
    27
    Likes (Received)
    40

    Default

    Lots of older editions on EBAY. Don't pay more than half the cost of a new one. I'm still using my 24th edition.
    Personally, I prefer the large hardcover version.

  25. #18
    Join Date
    Aug 2002
    Location
    Regina, Canada
    Posts
    2,331
    Post Thanks / Like
    Likes (Given)
    5
    Likes (Received)
    71

    Default

    Interesting how some replies answer the question and give useful info, others are condescending designed more to show how smart I am.
    Bob

  26. Likes Mike C. liked this post
  27. #19
    Join Date
    Apr 2012
    Location
    New Zealand
    Posts
    657
    Post Thanks / Like
    Likes (Given)
    160
    Likes (Received)
    188

    Default

    Quote Originally Posted by steve-l View Post
    There is no comparison between the machinery handbook and any slim pocketbook. The Machinery handbook has been in print for more than 100 yrs. My current edition is the 30th and there is a later one. It is just short of 3,000 pages in really, really small print. Jus sayin
    Reading comprehension test alert...
    The words "universally useful" are the key. The info you need, in your top pocket, without 3000 other pages of stuff you don't. The guy wants info on screw threads, pitches and stuff; let him master that before diverting to the minutiae of thread tolerances and thread measuring wires.

    The first copy I ever saw arrived by air in a torrent of swearing from a boss who wanted a job out yesterday. Glad it wasn't Machinery's.

  28. Likes litlerob1, machtool liked this post
  29. #20
    Join Date
    Jun 2004
    Location
    Melbourne Australia
    Posts
    5,456
    Post Thanks / Like

    Default

    Quote Originally Posted by Greenwud View Post
    Reading comprehension test alert...
    The words "universally useful" are the key. The info you need, in your top pocket, without 3000 other pages of stuff you don't. The guy wants info on screw threads, pitches and stuff; let him master that before diverting to the minutiae of thread tolerances and thread measuring wires.
    Mr. Wud makes a good point.

    If we go back to the O.P at post #1.

    Quote Originally Posted by Mk1_Oz View Post
    My lathe (Eriksen 180-NE) will cut 63 Standard Whitworth, 54 Metric and 40 Module thread types. I believe the 'module threads' means worm gears but am not sure.

    Will this machine do Imperial threads?
    It's fairly apparent, this guy is still back at the concept of T.P.I. With respect has has 63 available threads in Imperial pitches, yet wanted to know if he could cut U.S threads. All 63 of them will be derivatives of Threads Per Inch.

    Snowing him under with the 3000 pages of machinery's hand book wont help at this early stage.

    Bill had it covered by post #2.

    You do get a credit, I think you're the only one that has mentioned not disengaging the half nuts, if cutting T.P.I out of a metric screw.

    Regards phil.

  30. Likes snowshooze liked this post

Tags for this Thread

Bookmarks

Posting Permissions

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