ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

drafting standards third angle projection and first angle projection

Updated on November 11, 2013

The Concept of View Projection

Imagine you are creating a drawing of something that needs to be documented. In this case I'll use a car because most people can easily visualize one. Imagine that you need to create multiple views of that car so that someone else will able to build it.

You would need at least six views of that car to show all the parts in a measurable manner. You would need the Front View, the Right Side view, the Left Side view, the Top view, the Rear view and the Bottom view. Six views at minimum to show the vehicle accurately.

Imagine that there is a box around the car and the front, sides, top, bottom and rear views of the car are printed onto the inside of the box. When you unfold the box to reveal the interior you have the basic drawing layout used in drafting. There are possibly additional views, but these six are the fundamental elements for a design drawing.

America's Standard - Third Angle Projection

Third Angle Projection is the one of the means that multiple views are projected onto the interior planes of the imaginary six sided cube. This system is often described as visualizing the part on the inside of a bowl. Sitting at rest at the bottom of the bowl and looking straight down into it you see the Top view and as the part is slid up one side or another it reveals other views in turn.

Third Angle Projection drawings have a symbol showing the type of projection used. All drawings should have this symbol.

Personally I prefer this type of visualization, mostly because I'm used to it.

First Angle Projection Symbol

First Angle Projection Symbol
First Angle Projection Symbol
First Angle Projection using a cube
First Angle Projection using a cube
Third Angle Projection Symbol
Third Angle Projection Symbol
Third Angle Projection using a cube
Third Angle Projection using a cube

First Angle Projection

You tend to find First Angle Projection layouts in Europe. There is a symbol that should be on every drawing showing what system was used with the word METRIC prominently displayed.

This system uses the same six sided cube and bowl concept, but with a twist. And this is where it gets you.

The bowl is upside down.

That means that the image in the view is as if you are looking through the part not at the part. You are seeing the far side of the part on the plane, you are not seeing the side of the part facing you.

This takes a lot of getting used to and it is very easy to screw up the part when fabricating it. I had a report that my drawings, which were intended to be fabricated in the USA, were instead sent to Germany where they produced mirror imaged parts because the Germans failed to note the projection symbol. Oops.


    0 of 8192 characters used
    Post Comment

    No comments yet.


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)