Results 1 to 10 of 10

Thread: Trigonometry !

  1. #1
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,439

    Question Trigonometry !

    Hi Guys,

    A confession ! Trigonometry is not a strong point of mine !

    I'm trying to work out the ramp angle in order to move 10 Thou (0.25 mm) per mm over a 12 mm long slope. I keep getting 14 degrees ! That seems wrong somehow.

    Would some kind soul put me right, please !

    Thanks.
    Best Regards:
    Baron J.

  2. #2
    Join Date
    May 2020
    Location
    Willowbank QLD
    Posts
    517

    Default

    Baron

    I am not clear what you are asking, but that is irrelevant.

    Go to this link https://www.omnicalculator.com/math/...gle-side-angle or google triangle calculator.

    Put in the two known values and it will give you the rest.

    Steve

  3. #3
    Join Date
    Dec 2018
    Location
    NSW
    Posts
    586

    Default

    I think you need a bit more info. And clarification of what you have written.

    Trigonometry Calculator

    12mm ramp- is side c 12mm long (the hypotenuse), or side b?
    Assuming you want to find angle A

  4. #4
    Boringgeoff is offline Try not to be late, but never be early.
    Join Date
    Apr 2011
    Location
    Bakers Hill WA
    Age
    75
    Posts
    43

    Default

    BJ,
    I think 14 degrees is correct. You're looking at 3mm rise over a distance of 12mm. I just multiplied both numbers by ten (30mm -120mm) drew it on a piece of paper and measured with a compass and got 14 degrees.

    Cheers,
    Geoff.

  5. #5
    BobL is offline Member: Blue and white apron brigade
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    7,182

    Default

    0.25mm, in 1 mm

    if the 12 mm is the hypotenuse
    The "inverse tangent" of that is 14.04º

    If the 12 mm is the adjacent side
    The "inverse sine" of that is 14.47º

    I think either might do.

  6. #6
    Join Date
    Apr 2019
    Location
    Adelaide
    Posts
    589

    Default

    I can interpret the OP in 2 ways (prob both wrong);

    angle.jpg

    SOH => Sin X = 0.25/12 therefore X = 1.19*


    OR

    angle2.jpg

    SOH => Sin X = 0.25/1 therefore X = 14.48* and Y = 3.00mm

  7. #7
    Join Date
    Apr 2018
    Location
    Perth
    Posts
    168

  8. #8
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,439

    Default

    Wow ! You guys are brilliant !

    Many thanks for the confirmation that I'm right. 14.04 to 14.06 degrees is what I calculated. Eventually

    What I was trying to do was to work out how far up the slope I had to go to get a 10 thou change in height. The logic behind it is I want to use an M6 thread to obtain a ten thou per turn movement. So having two ramps back to back and pushing one ramp up the other will give me a 10 thou change in height.

    I hope that this makes sense !

    Thank you all for the help I owe you all a beer
    Best Regards:
    Baron J.

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

    Default

    Quote Originally Posted by BobL View Post
    if the 12 mm is the hypotenuse
    The "inverse tangent" of that is 14.04º
    Bob,
    the hypotenuse isn't used in the tangent calculation. It's opposite over adjacent (TOA)

    Quote Originally Posted by BobL View Post
    If the 12 mm is the adjacent side
    The "inverse sine" of that is 14.47º
    The adjacent side isn't used in the sine calculation. It's opposite over hypotenuse (SOH)

    If you can remember "sock it to her" (SOH CAH TOA), you'll never mess it up again.
    Chris

  10. #10
    Join Date
    Nov 2007
    Location
    melbourne australia
    Posts
    3,228

    Default

    Quote Originally Posted by Mk1_Oz View Post
    SOH => Sin X = 0.25/1 therefore X = 14.48*...
    14.48* is the correct answer.
    Chris

Similar Threads

  1. Turning Tapers & Trigonometry
    By Abratool in forum METALWORK GENERAL
    Replies: 17
    Last Post: 14th Jun 2012, 01:23 AM

Posting Permissions

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