Page 9 of 10 FirstFirst ... 78910 LastLast
Results 81 to 90 of 93

Thread: Friendly reminder...nearly all torque values are in foot pounds...

  1. #81
    Join Date
    Dec 2011
    Location
    East Tennessee
    Posts
    1,225
    Feedback Score
    10 (100%)
    Quote Originally Posted by Heavy Metal View Post
    Only an idiot thinks an inch-diameter fastener is measured in inch-pounds.

    Please name that gunsmith so we can ridicule and avoid him.
    Classic.... LOL... Ron

  2. #82
    Join Date
    May 2009
    Posts
    458
    Feedback Score
    21 (100%)
    Regarding a few of the earlier posts - the underlying reason that there is a specified, calculated torque range is to preload the assembly, such that the clamping force is greater than the anticipated loading (front, back, sideways, etc.). This preload prevents fatigue failures (repeated cyclic loading below the level of immediate failure leading to an eventual failure), excessive wear of the threads, loss of position, etc. Prevailing torque alone is not sufficient in high vibration environments to ensure that the assembly will maintain preload. That is where the stake comes in. If someone insufficiently torques the assembly, the best stakes on earth will not make any difference, as they add nothing to the mechanical strength of the joint/assembly.
    My assumption as to the slightly different specified torques between rifle and carbine assemblies would be that the different methods of rotation control (rifle butt stock vs receiver plate) and or other applied loading assumptions made the math come out differently, and rather than just round down or up, being good engineers, if the calculations came out different, then by God, that's what the manual should require.

  3. #83
    Join Date
    Oct 2010
    Posts
    2,246
    Feedback Score
    5 (100%)
    Great answer. Thanks for that. It confirms my belief that if there is a spec for something there's probably a good reason for it. I'll keep using the torque wrench, personally.


    Quote Originally Posted by spr1 View Post
    Regarding a few of the earlier posts - the underlying reason that there is a specified, calculated torque range is to preload the assembly, such that the clamping force is greater than the anticipated loading (front, back, sideways, etc.). This preload prevents fatigue failures (repeated cyclic loading below the level of immediate failure leading to an eventual failure), excessive wear of the threads, loss of position, etc. Prevailing torque alone is not sufficient in high vibration environments to ensure that the assembly will maintain preload. That is where the stake comes in. If someone insufficiently torques the assembly, the best stakes on earth will not make any difference, as they add nothing to the mechanical strength of the joint/assembly.
    My assumption as to the slightly different specified torques between rifle and carbine assemblies would be that the different methods of rotation control (rifle butt stock vs receiver plate) and or other applied loading assumptions made the math come out differently, and rather than just round down or up, being good engineers, if the calculations came out different, then by God, that's what the manual should require.

  4. #84
    Join Date
    Mar 2012
    Posts
    1,560
    Feedback Score
    0
    Quote Originally Posted by ryr8828 View Post
    Can you exceed 38 ft/lbs with a 6" long castle nut wrench?
    before the wrench breaks? if it's made well, sure.
    or are you saying it requires a lot of strength? in that case, slip a piece of pipe over the end of the wrench to increase leverage and mechanical advantage.

  5. #85
    Join Date
    Apr 2009
    Location
    Washington State
    Posts
    473
    Feedback Score
    0
    Quote Originally Posted by jay35 View Post
    if it's made well, sure.





  6. #86
    Join Date
    Jul 2010
    Location
    Cheyenne, Wyoming
    Posts
    444
    Feedback Score
    1 (100%)
    Quote Originally Posted by Raven Armament View Post
    I'm not trying to debate semantics, just trying to use correct terms for units.

    I was under the impression that kinetic energy is measured in foot-pounds and torque was measured in pound-feet and pound-inches.

    Does it differ between industries? Vehicle engine torque is expressed in lb-ft.

    I know energy is not torque.
    Yeah. Torque is Lb-ft/ Lb-in. Nobody pays any attention to the correct units though.

  7. #87
    Join Date
    Apr 2012
    Posts
    36
    Feedback Score
    0
    There is no difference between "foot-pound" and "pound-foot". Same as 3x5 = 5x3.

    Torque and energy do have the same units, force times length (lb*ft or N*m, which is also known as J)

  8. #88
    Join Date
    Jul 2010
    Location
    Cheyenne, Wyoming
    Posts
    444
    Feedback Score
    1 (100%)
    Quote Originally Posted by CompressionIgnition View Post
    There is no difference between "foot-pound" and "pound-foot". Same as 3x5 = 5x3.

    Torque and energy do have the same units, force times length (lb*ft or N*m, which is also known as J)
    http://en.wikipedia.org/wiki/Pound-foot_%28torque%29

  9. #89
    Join Date
    Jul 2009
    Posts
    2,177
    Feedback Score
    13 (100%)
    Quote Originally Posted by a0cake View Post
    For anybody who might want to download the "latest and greatest" here is the Nov 2008 version.

    For anyone further curious, the updated spec for the issue in question is on page 0025-8.

    http://kdeguns.com/ar-manual/M4%2016%2023Pchange8.pdf
    One of the best links ever! Thank you.

  10. #90
    Join Date
    Apr 2012
    Posts
    36
    Feedback Score
    0
    Lol @ Wikipedia article.

    Differentiating between foot-pound and pound-foot is purely a semantic construct. Scientifically the distinction is meaningless.

Page 9 of 10 FirstFirst ... 78910 LastLast

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
  •