TIPS FOR PROJECTION OF SOLIDS

 

 

solids.gif

When the axis of the solid inclined any of the projection plane,

  1. First assume the axis is perpendicular to that plane.
  2. Draw the projection in simple position
    1. Top view first if the axis is perpendicular to HP
    2. Front view first if the axis is perpendicular to VP
  3. Change position of the view to the given inclination
    1. Tilt the front view, if the axis inclined to the HP
    2. Tilt the top view, if the axis inclined to the VP
  4. Project from this view to get the final view
    1. Project from the front view, to get the top view if the axis inclined to the HP
    2. Project from the top view, to get the front view if the axis inclined to the VP
  5. Ensure all the points are named in an appropriate manner
    1. Lower case letters with a (‘)dash for the front views
    2. Lower case letters alone for the top views

Happy Drawing

Picture Courtesy:http://www.bbc.co.uk/schools/ks3bitesize/maths/shape_and_space/images/solids.gif

Tips for Projection of Straight Lines-II(Inclined to both planes)

Line inclined to both Planes

  1. The simplest position a straight line occupies in a space is, it is parallel to both V.P and H.P.
  2. The above position resulting in straight line as a top view and front view.
  3. For any other position first assume the given line parallel to both the planes.
  4. Then decide the view which will give us the true length of the line and true inclination. Draw locus line in both the points(ends)
  5. Rotate this view to the given angle to get the final view.
  6. Project from it to get the other final view (foreshortened view).
  7. Then ratate this foreshortened view to the locus of other point(end), to get the final views.

For example:

  • If a line is inclined to H.P, the front view will have the true length and true inclination.
  • Therefore rotate the front view to the given angle (θ -theta) and project this line to get foreshortened top view.
  • Rotate the foreshortened top view to the locus of other point, to get the final top view.
  • If a line is inclined to V.P, the top view will have the true length and true inclination.
  • Therefore rotate the top view to the given angle ( φ-phi) and project this line to get foreshortened front view.
  • then rotate the foreshortened front view to the locus of other point, to get the final front view.
Click the following link to download the power point show file for illustration of Projection of Lines
Power point on Projection of Lines – IIProjection of Lines – II

(Picture Coutesy:http://www.georgehart.com/cccg/Image71.jpg)

Your suggestions for my Engineering Graphics made easy book

I’m planning to write a book titled”Engineering Graphics made easy”

PL. find below the sample sheet of the book.

I thought of publishing it as a manual wherein student themselves draw the diagram(Bottom right corner)

Kindly offer your suggestions and ideas to make the book more useful and interesting.

Click the link example

2012 in review

HI every one I thank who’ve viewed my notes and commented constructively to make this blog still more useful

 

 

The WordPress.com stats helper monkeys prepared a 2012 annual report for this blog.

Here’s an excerpt:

4,329 films were submitted to the 2012 Cannes Film Festival. This blog had 53,000 views in 2012. If each view were a film, this blog would power 12 Film Festivals

Click here to see the complete report.

An advance tamil new year gift

HI Every one,

here is a New Year gift for every one

i’m enclosing a book on behavioral economics in Tamil as a New Year Gift.

Happy learning

அன்புடையீர்,
உங்கள் அனைவருக்கும் எனது
இனிய தமிழ் புத்தாண்டு வாழ்த்துக்கள்
கூடவே ஒரு இனிய பரிசு இணைக்கப்பட்டுள்ள பட வடிவக் கோப்பினை தரவிறக்கம் செய்து வாசிக்கவும்.

நட்புடன்
மணி

Dr. G. Manikandan, M.E., Ph.D
Professor & Head
Department of Mechanical Engineering
Velammal College of Engineering and Technology
Madurai – 625 009
Tamilnadu
0452-2465285, 2465289

the first tamil book on behavioral economics.pdf

2011 in review

The WordPress.com stats helper monkeys prepared a 2011 annual report for this blog.

Here’s an excerpt:

The concert hall at the Syndey Opera House holds 2,700 people. This blog was viewed about 49,000 times in 2011. If it were a concert at Sydney Opera House, it would take about 18 sold-out performances for that many people to see it.

Click here to see the complete report.

TEst

Dos’ and Don’ts’ in the University Exam

Dear Students,

First of all I wish to thank all my colleagues for sharing their thoughts on this topic and helping me to write such a thing.

Velammal College of Engineering and Technology

Viraganoor, Madurai – 625009.

Department of Mechanical Engineering

Free Hand Sketching

S.No Do s Don’ts
1. Name the Views
2. Placed in proper position Don’t use scale for free hand sketching.
3. If arrow head is not given in the drawing , most informative side should be taken as F.V
4. Ensure top view properly with out confusing with other views.
5. Invisible lines should be drawn using dotted line.

Conic sections and Special Curves

S.No Do s Don’ts
6. Eccentricity value should be converted into fraction. Avoid using compass for drawing circular invaluable.
7. Eccentricity value should be noted at the curve.
8. Use proper scaling while drawing conic sections for larger values.
9. Indicate tangent & normal properly.
10. Mark the axis of centre for epicycloids & Hypocycloid.
11. Care should be taken while numbering the generating circle for special Curves.

Projection of Points, Lines and Planes

S.No Do s Don’ts
1. Use proper notation 

Front View – lower case letters with (a’) top view    – lower case letters.

Avoid capital letters in Front View & Top view, 

Avoid using projectors as a dimensioning line.

2. Lines  

Ө+ Ø = 90 0 both front view & top view in Perpendicular.

Avoid drawing the projectors in thick line.
3. Final projections should be thick line
3. Write down the TL, Ө,Ø, α, β separately.
4. Ensure Angle of inclination properly.
5. Planes  

Take surface inclination first.

Projections of Solids

S.No Do s Don’ts
1. Ensure whether the question is Prism or Pyramid Don’t extent the projectors from the true shape beyond the reference line.
2. For pyramid in the true shape draw the slant edges.
3. Mark the axis & dotted line properly. Don’t forget to draw the boundary of any view.
4. Ensure resting part of solid properly. Don’t draw the axis line as dotted line.
5. Ensure given inclinations are marked properly.
6. Make sure that the axis & base edge is always perpendicular to each other.
7. While getting the final view, name the intersection of projector properly.
8. Name all the points properly.

Section of Solids

S.No Do s Don’ts
1. Proper location of cutting planes Avoid using dotted line for sectional line.
2. Make double sure the section plane inclination with respect to reference line. Avoid using dark line while hatching the true shape & sectional view.
3. Draw the section plane line properly (for pyramid & cone).
4. Make sure that point of intersection of section plane and axis/edges coincide the axis transferred properly.
5. True shape should be drawn using perpendicular projectors from the cutting plane.
Development of surface
S.No Do s Don’ts
1. Use capital letters while drawing developed surfaces. Avoid drawing thick lines while developing cylinder & cone.
2. Draw smooth curve for joining points in truncated cone & cylinder. Avoid joining the points using free hand curve.( For truncated prism and pyramid)
3. For pyramid draw the base edges Don‘t draw the base edges for cone.
4. Draw the removed portions using thin lines.

Isometric view

S.No Do s Don’ts
1. Use only co ordinate method for pyramid & cones. Don’t draw the box using hick lines.
2. Ensure circle is drawn using 4 Centre method with compass. Don’t for get to add & small note. 

“For the sake of convenience Isometric view is drawn “Since Isometric length = 0.816 X True length”.

Perspective view

S.No Do s Don’ts
1. Use capital letters for final view only. Don’t dimensioning the values with in the visual ray

General Points

1. Answer the questions familiar to you first.

2. Don’t forget to write the proper question number.

3. even if correct solution with out question number carries zero mark.

4. Differentiate thick line, thin line, dotted line, Axis line, section plane line properly using appropriate pencil.

5. Avoid shuffling of the given data.

6.  Write all   dimensions are in mm & scale ratio if applicable.

7. Don’t attempt to give details beyond the questions.

8. Make sure that all the given data are dimensioned in your solution.

9. Manage the time properly (for eg: 30 minutes per solution)

10. Use the last 30 minutes to verify all the above points.

Hope you all follow the above points and will secure good marks.

Wish you all the very best.

Dr. G. Manikandan

2010 in review

Dear Viewers thanks and new year wishes!

Dr. G. Manikandan

 

The stats helper monkeys at WordPress.com mulled over how this blog did in 2010, and here’s a high level summary of its overall blog health:

Healthy blog!

The Blog-Health-o-Meter™ reads Wow.

Crunchy numbers

Featured image

About 3 million people visit the Taj Mahal every year. This blog was viewed about 46,000 times in 2010. If it were the Taj Mahal, it would take about 6 days for that many people to see it.

 

In 2010, there was 1 new post, growing the total archive of this blog to 17 posts.

The busiest day of the year was November 17th with 633 views. The most popular post that day was TIPS FOR PROJECTION OF SOLIDS.

Where did they come from?

The top referring sites in 2010 were google.co.in, cempunnapra.blogspot.com, en.wordpress.com, enggdrawing.blogspot.com, and facebook.com.

Some visitors came searching, mostly for solids, projection of solids, projection of points, engineering graphics, and projection of lines.

Attractions in 2010

These are the posts and pages that got the most views in 2010.

1

TIPS FOR PROJECTION OF SOLIDS November 2007
58 comments

2

Projection of Lines – I (Inclined to only one plane) September 2008
12 comments

3

Problems in Projection of Points – 2008-09 September 2008
21 comments

4

Questions on Projections of Solids and Section of Solids October 2008
10 comments

5

Engineering Graphics getting started, Points, Lines… November 2008
19 comments