• Home
  • Download PDF
  • Order CD-ROM
  • Order in Print
BASIC  DRAFTING  TECHNIQUES
VERTICAL  LINES

Engineering Aid 3 - Beginning Structural engineering guide book
Page Navigation
  61    62    63    64    65  66  67    68    69    70    71  
main purpose of making your first drawings is to learn   to   use   instruments.   Each   drawing   will offer an opportunity for practice. Later on, good form  in  the  use  of  instruments  will  become  a natural habit. Accurate  pencil  drawings  are  of  first  importance since all inked drawings and tracings are made from finished pencil drawings. It is a mistake to believe that a poor pencil drawing can be corrected when  you  make  the  ink  tracing.  Any  drawing important  enough  to  be  inked  or  traced  in  ink must  be  accurate,  legible,  and  neat.  Because  most military and commercial blueprints are made from pencil drawings, ambitious trainees will work to acquire skill in pencil drawing as they perfect their technique.   Good   technique   and   skillful   pencil drawing  are  basic  to  proficiency  in  drafting. The  following  sections  will  guide  you  in attaching  your  drawing  paper  to  the  board  and in drawing basic lines with the T square, triangles, and  pencil. ATTACHMENT  OF  PAPER TO  THE  BOARD Now that you have become relatively familiar with your equipment and materials, it is time to get started by attaching your drafting paper to the board.  The  sheet  should  be  placed  close  to  the  left edge of the drafting board. Working in this area makes the T square easier to handle and reduces the  likelihood  of  error  because  of  T  square “swing.” The drafting sheet should be far enough from  the  bottom  of  the  board  (about  3  in.)  to ensure firm support for the head of the T square when  you  are  drawing  at  the  lower  part  of  the sheet. A drawing sheet properly attached to the board  on  which  a  T  square  is  used  is  shown  in figure  3-2.  After  aligning  the  drawing  sheet, smooth  out  any  wrinkles  and  fasten  the  four corners with short strips of drafting tape. If you are   attaching   large   sheets,   you   should   place additional  strips  of  tape  at  the  top  and  bottom edges  of  the  sheet.  Drafting  tape  has  a  lighter coating  of  adhesive  than  does  masking  tape. Consequently, it will hold the drawing firmly, yet can  be  removed  without  tearing  or  marring  the drawing. If you use masking tape or transparent tape, leave a large margin in the event you tear the paper when removing the tape. When placed diagonally  across  the  corners  of  the  sheet,  as shown  in  figure  3-2,  the  drafting  tape  offers little obstruction to movement of the T square and triangles. Avoid the use of thumbtacks; they will eventually  ruin  the  drafting  board. If you are using a parallel straightedge or draft- ing machine instead of a T square, the procedure just  described  is  the  same  with  one  exception. Instead of placing the paper close to the left edge of  the  board,  you  should  place  it  approximately at  the  midpoint  of  the  length  of  the  parallel straightedge  or  in  the  center  of  the  drawing  board surface when you are using a drafting machine. HORIZONTAL  LINES by The  draftsman’s  horizontal  line  is  constructed drawing from left to right along the working Figure 3-2.-Attaching drafting paper to the board. 29.275 Figure 3-3.-Construction of basic lines. 3-4







Western Governors University

Privacy Statement
Press Release
Contact

© Copyright Integrated Publishing, Inc.. All Rights Reserved. Design by Strategico.