Class 2 presentation postedPresentation Transcript
Instructor: Laura Gerold, PE Catalog #10614113 Class # 22784, 24113, 24136, & 24138Class Start: January 18, 2012 Class End: May 16, 2012
“Jefferson had a precise and detailed sense of geography. Had he not been so busy with all of his other interests and obligations, one might imagine him as an important mapmaker, with his passion for accurate representation, his draftsmanshipand devotion to the study of land.” Lions of the West by Robert Morgan (2011)
Create a set of hand-sketched plans that include the following: Drawing Border Scale Six Orthographic Standard Views (page 165 text) Auxiliary Views (If Needed) Section View(s) Dimensions
The system of views is called multiview projection. Each view providescertain definite information (Chapter 5).
Items Appropriate for the Project Items Not Appropriate for the Project
2/22/12 – Project Proposal Due (10 Points) Write a brief memo describing the object you plan on drawing including plans for how to scale the object. Memo should include the following information in the header: To: Laura Gerold From: Thomas Jefferson Date: February 22, 2012 Subject: Teakettle Project Plans for 2D Essentials Memo should also include a photo or a freehand sketch of your item.
4/4/12 – 50% Project Plans Due (30 points) Turn in what you have drawn so far and comments will be added to your plans on Post- it notes. Plans at this point should include: scale drawing border three views
5/9/12 – Final Plans Due including all elements (100 points) 5/16/12 – Plans returned with score (140 points total including proposal, 50% plans, and final)
Thick and Thin Drawing LinesFreehand line techniqueLine styles
ALPHABET OF LINES• Visible Line – The line that you can see when viewing an object. It should indicate all visible edges of an object. They should stand out clearly in contrast to other lines so the shape of an object is apparent to the eye.• Hidden Line - Used to show surfaces, edges, or corners of an object that are hidden from view
ALPHABET OF LINES• Section Line – Used to indicate the surface in the section view imagined to have been cut along the cutting plane line.• Centerline – Centerlines are used to show symmetrical features. Examples are the center of holes or roads.• Symmetry – Symmetry lines are used when partial views of symmetrical parts are drawn.
ALPHABET OF LINES• Dimension and Extension Lines– Used when dimensioning an object.• Leaders – Used to indicate the part of the drawing to which the note or description refers. Arrowheads should touch the object lines.
ALPHABET OF LINES• Cutting-plane Lines– Used to designate where an imaginary cutting took place.• Viewing-plane lines – Used to indicate direction of sight when a partial view is used.• Same lines used for both.
ALPHABET OF LINES• Short-break Line– Used when it is desirable to shorten the view of a long part.• Long-break Line– Same definition as short-break line
ALPHABET OF LINES• Phantom Line – Used to indicate alternate position of moving parts, adjacent position of moving parts, adjacent position of related parts, and repetitive detail. It represents a feature or component that is not part of the specified part or assembly. E.g. billet ends that may be used for testing, or the machined product that is the focus of a tooling drawing.• Stitch Line – Used for indicating a sewing or stitching process.• Chain Line - Used to indicate that a surface or zone to receive additional treatment or considerations.
Coffee Mug Project (Freehand Draw) Visible Lines Hidden Lines Centerline Symmetry Line Dimension Line (make up a dimension!) Leader Cutting-plane Line Short-break Line
The main difference between an instrument or CAD drawing and a freehandsketch is in the appearance of the lines. A good freehand line is not expected tobe precisely straight or exactly uniform, as is a CAD or instrument-drawn line.Freehand lines show freedom and variety. Freehand construction lines are very light, rough lines. All other lines should be dark and clean.
U.S. Customary Units The Metric SystemDual-Dimensioned
• Drawing scale is the reduction or enlargement of the drawn object relative to the real object.• On a scale of 1:2, the first number, 1 represents the size of the object on the drawing. The second number, 2, represents the size of the object in the real world.Reduced and Enlarged Scale. Many drawings must be shown at reduced scale for theobject to fit on the paper.
For a part that is shownon the paper at half itsactual size, the scale islisted in one of these threeways: SCALE: 1:2 SCALE: 1/2 SCALE: .5Architectural drawings listthe scale based on thenumber of fractions of aninch on the drawing thatrepresent one foot on theactual object. Example: List the predominant drawing scale in the title block. (Courtesy of Dynojet Research, Inc.) SCALE: 1/8" 1
Scales are measuringtools used to quicklyenlarge or reduceDrawingmeasurements. Types of Scales
An engineers’ scale (also called a civil engineers’ scales) is a decimalscale graduated in units of 1 inch divided into 10, 20, 30, 40, 50, and 60parts. Because the engineers’ scale divides inches into decimal units, it is convenient in machine drawing to set off inch dimensions expressed in decimals.
Engineers scales are usually used for large areas that you are trying to “scale down” for use on large scale plans or maps Use Decimals 1:10 Scale, 1” = 1’, then each division is equal to 0.1 ft. 1:10 scale is equal to 1” = 10’, 100’, 1000’ 10 Scale can be used as a ruler and can be used to set off inch dimensions as decimals To make a half size drawing from an original drawing that used a 10 scale, use a 20 scale
Measure Pipe and Stone Drains Length on Bioretention Plan Apply an engineer scale to an object Draw a 62.5’ x 84.8’ Room
Full Size 1:1 scaleThe triangular scales haveone full-size scale and fivereduced-size scales, allfully divided.Using these scales, adrawing can be made fullsize, enlarged sized, orreduced sized. Half Size 1:2 scale
Similar to engineer scale, but using metric system Full Size is 1:1 scale Division is 1 mm in width with calibrations at 10 mm intervals Half Size is 1:2 Scale Division is 2 mm in width with calibrations at 20 mm intervals Used for maps, force diagrams, graphical constructions with scales such as 1 mm = 1 kg
The architects’ scale is intended primarily for drawings of buildings, pipingsystems, and other large structures that must be drawn to a reduced scaleto fit on a sheet of paper. AutoCAD software users sometimes become confused using architectural units. When selecting architectural units and entering lengths, keep in mind that a value of 1 is one inch, not one foot. How To Architect - Scale
On an architect scale, 1/8” = 1’ Full Size 16 Scale – Sixteen divisions per inch Half Size To create half size plans, use the full size scale and divide every dimension by two Do not use the ½ scale, which is ½ = 1” Double Size Use your full size scale and multiply everything by two
1/16 or 1/8 scale is typically used for overall building plan dimensions ¼ is used for detail plans 3/8, ½, 1 are used for large details (building sections) ¾ and 1 ½ are used for details
Measure Plans Apply an architect scale to an object Draw a 15’-2” x 25’-4” Room
Mechanical engineers’ scales are divided into units representing inchesto full size, half size, quarter size, or eighth size.To draw an object to a scale of half size, for example, use the mechanicalengineers’ scale marked half size, which is graduated so that ever ½”represents 1". In other words, the half-size scale is simply a full-size scalecompressed to half size. Triangular combination scales are available that include full- and half-size mechanical engineers’ scales, several architects’ scales, and an engineers’ scale all on one stick.
Lettered text is often necessary to completely describe an object or toprovide detailed specifications. Lettering should be legible, be easy tocreate, and use styles acceptable for traditional drawing and CAD drawing. Engineering drawings use single-stroke sans serif letters because they are highly legible and quick to draw. Sans serif means without serifs, or spurs
• Most hand-drawn notes use lettering about 3 mm (1/8") high. • CAD notes are set using the keyboard and sized to be in the range of 3 mm (1/8") tall according to the plotted size of the drawing.An Example of Lettering and Titles Using CAD • CAD drawings typically use a Gothic lettering style but often useWhen adding lettering to a a Roman style for titles.CAD drawing, a good rule ofthumb is not to use more thantwo fonts within the samedrawing.
The proportionsof vertical capitalletters and numbersare shown
Lowercase letters are rarely used in engineering sketches except forlettering large volumes of notes. Vertical lowercase letters are used onmap drawings, but very seldom on machine drawings. When large and small capitals are combined, the small capitals should be three fifths to two thirds the height of the large capitals.
Inclined (italic)capital letters andnumerals, aresimilar to verticalcharacters, exceptfor the slope. Theslope of the letters isabout 68° from thehorizontal.
Do’s & Don’t• Never let numerals touch the fraction bar.• Center the denominator under the numerator.• Avoid using an inclined fraction bar, except when lettering in a narrow space, as in a parts list.• Make the fraction bar slightly longer than the widest part of the fraction.
Use extremely light horizontal guidelines to keep letter height uniform… Do not use vertical guidelines to space the distance from one letter to the next within a word or sentence.For even freehand letters:• Use 1/8" gridded paper for drawing to make lettering easy.• Use a scale and set off a series of spaces, making both the letters and the spaces between lines of letters 1/8" high.• Use a guideline template like the Berol Rapidesign 925• For whole numbers and fractions, draw five equally spaced guidelines.
Spacing between LettersUniform spacing between letters is done byeye. Contrary to what might seem logical,putting equal distances from letter to lettercauses them to appear unequally spaced.Spacing between WordsSpace letters closely within words tomake each word a compact unit, butspace words well enough apart to clearlyseparate them from adjacent words.Spacing between RowsBe sure to leave space between rows oflettering, usually equal to the letter height.
In most cases, the title andrelated information arelettered in title boxes or titlestripsWhen lettering by hand,arrange the title symmetricallyabout an imaginary centerline
How to Write Like an Architect Use a Ruler for even lines Use the Ames Lettering Guide Lettering Example (Worksheet 2) Lettering Example (Finish Plan)
High-quality drawing pencils help produce good quality technical sketches and drawings.Hard Medium SoftThe hard leads in this These grades are for These leads are toogroup (left) are used general-purpose work in soft to be useful inwhere extreme technical drawing. The mechanical drafting.accuracy is required, softer grades (right) are They tend to produceas on graphical used for technical sketching, smudged, rough linescomputations and lettering, arrowheads, that are hard to erase,charts and diagrams. and other freehand work and the lead must beThe softer leads in this on mechanical drawings. sharpened continually.group (right) are The harder leads (left) are These grades are usedsometimes used for used for line work on for artwork of variousline work on machine drawings and kinds, and for full-sizeengineering drawings, architectural drawings. The details in architecturalbut their use is limited H and 2H leads are widely drawing.because the lines are used on pencil tracings forapt to be too light. reproduction.
You might be surprised how much your drawings benefit from finding a style of pencilthat suits your use. Soft pencils, such as HB or F, are mainly used in freehandsketching.Choose a pencil that:• Is soft enough to produce clear black lines, but hard enough not to smudge too easily.• Is not so soft that the point breaks easily.• Feels comfortable in your hand.• Grips the lead without slipping.
Many choices of media (paper and other) are available for particularsketching or drawing purposes. Whether you are sketching or are plottinga drawing from a CAD workstation, choose the type of sheet and size thatsuits your needs.Small notebooks or sketch padsare useful when working at a siteor when it is necessary to quicklyrecord information.Graph paper can be helpful inmaking neat sketches Sketch on Graph Paper
There are ANSI/ASME standards for international and U.S. sheetsizes. Note that drawing sheet size is given as height width. Moststandard sheets use what is called a “landscape” orientation. * May also be used as a vertical sheet size at 11" tall by 8.5" wide.
• Margins and Borders• Zones
The title block is located in the lower right corner of the format.Standard areas in the title block provide the information asshown below.
When laying out a drawing sheet, you willneed to consider:• the size and scale of the object you will show• the sheet size• the measurement system (units) for the drawing• the space necessary for standard notes and title block.The object you are drawing is the “star” of the sketch. Keep the objectnear the center of the sheet. It should be boldly drawn, usingthick visible lines. Make it large enough to fill most of the sheet and so thatdetails show clearly