Notices
Results 1 to 7 of 7

Thread: drawing 3D geometry

  1. #1 drawing 3D geometry 
    Forum Masters Degree organic god's Avatar
    Join Date
    Feb 2008
    Location
    London
    Posts
    567
    often when dealing with a geometry problem i draw a sketch. however i find it impossible to draw a 3D vector or point onto a piece of paper.

    Does anyone know of any techniques or way around this problem.

    I tried drawing a x,y and z axis but it didnt work surprisingly


    everything is mathematical.
    Reply With Quote  
     

  2.  
     

  3. #2  
    Suspended
    Join Date
    Apr 2007
    Location
    Pennsylvania
    Posts
    8,795
    Mechanical engineers use isometric projections

    http://en.wikipedia.org/wiki/Isometric_projection

    I imagine a computer program like autocad would make it easier.


    Reply With Quote  
     

  4. #3 Re: drawing 3D geometry 
    Suspended
    Join Date
    Apr 2008
    Posts
    2,176
    Quote Originally Posted by organic god
    often when dealing with a geometry problem i draw a sketch. however i find it impossible to draw a 3D vector or point onto a piece of paper.

    Does anyone know of any techniques or way around this problem.

    I tried drawing a x,y and z axis but it didnt work surprisingly

    It is hard to show 3D without loosing the actual angles involved to create the object. What looks like a 120 degree angle on paper is often a 90 degree angle in real life.

    That is why you cannot just walk up to a house, take a picture, pop it into the computer and have the computer figure out how big a hand rail you need for the porch. There is just to much distortion, to much lost in two dimensions.

    We usually make it up with text, dimensions or notes.



    Sincerely,


    William McCormick
    Reply With Quote  
     

  5. #4  
    Forum Masters Degree bit4bit's Avatar
    Join Date
    Jul 2007
    Posts
    621
    I learnt a way using single point and double point perspectives, which gives you nice neat 3D sketches, but not accurate scale models. For once, I agree with William, adding dimensions to a sketch gives you all the info you need. Personally I use Solidworks now...which is all you'll ever need for mechanical design.
    Chance favours the prepared mind.
    Reply With Quote  
     

  6. #5  
    Suspended
    Join Date
    Apr 2008
    Posts
    2,176
    Quote Originally Posted by bit4bit
    I learnt a way using single point and double point perspectives, which gives you nice neat 3D sketches, but not accurate scale models. For once, I agree with William, adding dimensions to a sketch gives you all the info you need. Personally I use Solidworks now...which is all you'll ever need for mechanical design.

    Could you create a little solid works drawing similar to mine, and show how solid works displays angles and such?

    I would appreciate it.


    Sincerely,


    William McCormick
    Reply With Quote  
     

  7. #6  
    Forum Masters Degree bit4bit's Avatar
    Join Date
    Jul 2007
    Posts
    621
    Chance favours the prepared mind.
    Reply With Quote  
     

  8. #7  
    Suspended
    Join Date
    Apr 2008
    Posts
    2,176
    Quote Originally Posted by bit4bit
    That is a nice 3D drawing.

    I was wondering though, how does that programs tools for showing actual angles, either angles input manually or automatically look? Is it a time consuming thing or something simple?

    I am assuming that solid works can output to cam (Computer Aided Machining/Manufacturing) applications? Or offers an interface to popular devices or standards?

    Sincerely,


    William McCormick
    Reply With Quote  
     

Bookmarks
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
  •