The principles rules of dimensioning.

I am fanatic about rules , I'll try always to be attentive during dimensioning so I publish some basic rules in dimensioning.

1. Each feature of an object is dimensioned once and only once.

2. Dimensions should be selected to suit the function of the object.

3. Dimensions should be placed in the most descriptive view of the feature being dimensioned.

4. Dimensions should specify only the size of a feature. The manufacturing method should only be specified if it is a mandatory design requirement.

5. Angles shown on drawings as right angles are assumed to be 90 degrees unless otherwise specified, and they need not be dimensioned.

6. Dimensions should be located outside the boundaries of the object whenever possible.

7. Dimension lines should be aligned and grouped where possible to promote clarity and uniform  appearance.

8. Crossed dimension lines should be avoided whenever possible. When dimension lines must cross, they should be unbroken.

9. The space between the first dimension line and the object should be at least 3/8 inch (10 mm).

The space between dimension lines should be at least 1/4 inch (6 mm).

10. There should be a visible gap between the object and the origin of an extension line.

11. Extension lines should extend 1/8 inch (3 mm) beyond the last dimension line.

12. Extension lines should be broken if they cross or are close to arrowheads.

13. Leader lines used to dimension circles or arcs should be radial.

14. Dimensions should be oriented to be read from the bottom of the drawing.

15. Diameters are dimensioned with a numerical value preceded by the diameter symbol.

16. Concentric circles should be dimensioned in a longitudinal view whenever possible.

17. Radii are dimensioned with a numerical value preceded by the radius symbol.

18. When a dimension is given to the center of an arc or radius, a small cross is shown at the center.

19. The depth of a blind hole may be specified in a note. The depth is measured from the surface of the object to the deepest point where the hole still measures a full diameter in width.

20. Counterbored, spotfaced, or countersunk holes should be specified in a note.

What Are Some Basic Traits of a Good CAD Drafter?

Are you new to CAD or a CAD beginner, and have ever thought to yourself, “What are some basic traits of a good CAD drafter?” If yes, then this is the article for you!

To answer this question let’s look at that www.bls.gov website, which states that “Drafters prepare technical drawings and plans, which are used by production and construction workers to build everything from microchips to skyscrapers.” As you can see, this statement is specific, yet also broad. It is specific in that it states that “Drafters prepare technical drawings and plans…”, and it is broad in that it states “…to build everything from microchips to skyscrapers.”

From the statement above it can be understood that a good CAD Drafter would need to be technically minded. He’d have to have problem solving abilities, the kind which are generally associated with math or being able to visualize things in three dimensions.

It can also be understood from the BLS statement that a good CAD Drafter would have to have familiarity with a specific industry, and be able to translate that knowledge into creating drawings that would be useful to production or construction workers.

In addition to the traits already mentioned, a good CAD Drafter would be able to think in terms of the “big picture”. He’d be able to understand that his job would just be a part in creating an product. This awareness would lead him to create more useful drawings.

Lastly, a good CAD Drafter would have to be proficient in the CAD software of his industry.

To summarize, a good CAD Drafter would be one that is technically minded, has industry specific knowledge, could think in terms of the “big picture”, and would be proficient in the CAD software of his industry. If this doesn’t describe you, don’t fret. Everyone starts somewhere, and these could be your goals for becoming a good CAD Drafter! It’s been said that “nothing comes without effort”!!

Many thanks to Brian M Curran.

LOCAL.QUALIFIED.TRUSTED
118-11 84TH AVENUE, #503
KEW GARDENS (QUEENS), NY 11415
T./F. 718.441.3968
C. 347.416.4226
WWW.DRAFTINGSERVICES.COM

Keyboard in AutoCAD

For AutoCAD veterans users I have listed all shortcuts of keyboard.

See all keyboards shortcuts and use them.


F1 - displays help

F2 - displays text window

F3 - switches object snaps

F4 - toggles table mode

F5 - toggles isometric planes

F6 - toggles DUCS (switches coordinate display, till A2006)

F7 - toggles grid display

F8 - toggles ortho mode

F9 - toggles snap

F10 - toggles polar tracing

F11 - toggles object tracing

F12 - toggles dynamic input (2006+)



ESC - cancel changes, cancel grips

TAB - cycles osnaps

SHIFT - (on object selection) removes objects

DEL - erases objects (hold when pointing)



Ctrl+0 - toggles clean-screen mode (2004+)

Ctrl+1 - displays Properties window

Ctrl+2 - displays DesignCenter window

Ctrl+3 - displays Tool palette (2004+)

Ctrl+4 - displays Sheet Set Manager, or Content Manager (2005+, ADT2004)

Ctrl+5 - displays Info Palette, or Project Navigator (2005-2007, ADT2004)

Ctrl+6 - displays dBConnect window

Ctrl+7 - displays Markup Manager (2005)

Ctrl+8 - displays Quick Calculator (2006+)

Ctrl+9 - shows/hides Command line (2006+)



Ctrl+A - selects all thawed objects (2002)

Ctrl+Shift+A - toggles group selection (group/single)

Ctrl+B - toggles snap

Ctrl+C - copies content to Clipboard

Ctrl+Shift+C - copies with reference point

Ctrl+D - toggles coordinates display (dynamic UCS, till 2009)

Ctrl+E - switches isoplanes

Ctrl+Shift+E - pull a region to 3D (PRESSPULL, since 2010)

Ctrl+F - toggles osnaps

Ctrl+G - toggles grid display

Ctrl+H - toggles Pickstyle (group and hatch selection)

Ctrl+Shift+H - toggles Palettes display (2009+)

Ctrl+I - toggles coordinate display (2009+)

Ctrl+J - repeats the last command (Enter)

Ctrl+K - displays the Hyperlink dialog

Ctrl+L - toggles Ortho mode

Ctrl+N - starts new drawing

Ctrl+O - opens a drawing

Ctrl+P - print a drawing

Ctrl+Shift+P - toggles Quick Properties display (2009+)

Ctrl+Q - quits AutoCAD (2004+)

Ctrl+R - switches to the next viewport

Ctrl+S - saves drawing

Ctrl+Shift+S - saves drawing as (2004+)

Ctrl+T - toggles the Tablet mode

Ctrl+U - switches polar tracing

Ctrl+V - pastes the Clipboard contents

Ctrl+Shift+V - pastes contents as block

Ctrl+W - toggles object tracing

Ctrl+X - cuts contents to the Clipboard

Ctrl+Y - redoes the undone action

Ctrl+Z - undoes the last action

Ctrl+PgDn - switches to the next layout (2004+)

Ctrl+PgUp - switches to the previous layout (2004+)





Alt+F8 - VBA macros

Alt+F11 - VBA editor



Temporary override keys (2006+):

Shift - switches ortho mode

Shift+- switches dynamic UCS mode (2007+)

Shift+)- switches object tracing mode (2007+)

Shift+. switches polar mode

Shift+A - switches osnaps

Shift+E - switches endpoint osnap

Shift+C - switches center osnap

Shift+D - disables osnaps and tracing

Shift+M - switches middle osnap

Shift+Q - switches object tracing osnap

Shift+S - enables osnap override

Shift+W - starts SteeringWheel (A2009+)

Shift+X - switches polar tracing



CTRL+mouse - cycles selection of overlapping objects (till 2006)

Shift+space - cycles selection of overlapping objects in 2D (2007+)

CTRL+space - cycles selection of overlapping sub-objects in 3D (2007+)

CTRL+ALT - extrudes the selected region into 3D - PRESSPULL (2007+)

CTRL+arrow - moves cursor

Arrow up/down - command history



CTRL+SHIFT+letter - goes to the property in the Properties window

ALT+down arrow - opens a list in the Properties window

ALT+up arrow - closes a list in the Properties window

Of course all the Windows shortcut keys remain active as well (Ctrl+Tab, Ctrl+F3, Ctrl+F6 etc.). Other shortcuts may be defined as user keys in the ACCELERATORS section of your AutoCAD menu. Since AutoCAD version 2006 you can also use CUI to define so called temporary override keys.

Thanks CADFORUM.CZ

An Example Inventor Animation.

This is a sample animation created with Autodesk Inventor R10.
See and You.

Books I recommend to became powerful in Mechanical Engineering Drafting.

Every engineer must master at least the basics of graphics, sketching, and modeling--both freehand and computer-assisted.

Whatever your artistic talents, these books will give you the skills you need to develop your visualization skills and right methods to draw as a proffesional engineer.




So I will recommand to read and study at least one of book those authors.







 



This book is written by Prof.Emeritus James H.Earle

For me is the best Author in teaching books for engineering design graphics .

With books of James H.Earle we became more practical in field of engineering graphics.

.





This book is very practical in engineering graphics also associated with Autodesk Inventor.

For the passionated of Autodesk Inventor the books of James D.Bethune are the best on world .

Engineering Graphics 14th-edition is written by legends of Technical Drawings in World.

I haven't anything to say more about it.










So I think these books have a role in basic education of engineering design graphics for students and mechanical engineers .
But we can't forget this. "The computer graphics is a primary-medium but RULES REMAIN RULES."

Times has Changed.

When I was 14-old year on the my test in school I had solving the second grade
equation Ax^2+bx+c=0 .
Now I solved it with AutoLISP .Check and you.
;;; Copyright (c) 2008 Ing.Arben Allaraj
;;; Program that solve equation of second grade.
;;; For more information contact to me.
;;; Modified by Bill Kramer.

(defun C:Grade2 ( / A B C D E F G)
(setq A (getreal "\nEnter the A value: ")
B (getreal " B value: ")
C (getreal " C value: ")
)
(cond
((zerop A)
(prompt "\nA value invalid, cannot be zero."))
((minusp (setq E (- (* B B) (* 4 A C))))
(prompt "\nB^2 - 4AC must be greater than zero to solve."))
(T
(setq D (+ (- B)(sqrt E))
F (/ D (* 2 A))
H (- (- B)(sqrt E))
G (/ H (* 2 A))
)
(prompt (strcat "\nSolution X1="
(rtos F)
", X2="
(rtos G)
))
)
)
(princ)
)