The UK’s national standard for engineering drawings is BS 8888. This defines the requirementsfor a drawing of a products and their component parts. This standard is uniqueto the United Kingdom but some other countries use similar national standards.The BS 8888 covers many different aspects within the UK and national drawings.It gives Technical Product Specification like:· Principles· Allows drawings to be done in 2D or 3D· Gives letter and number requirements· Gives dimensionsIt gives information on Tolerances:· Linear tolerances, which includes limits andfits· Geometrical tolerances · General tolerances, which includes BS EN 22768· Surface textures and finishes· Edge tolerancesIt gives Geometrical Product Specification:· The 4 geometrical properties· The 7 step systemIt gives features and features of the size.
It also givessize tolerances and things like the Envelope Requirement and ISO 14405-1. Alsoit shows many different markings on drawings and allows for compliance to thestandard and also allows for the implementation of the standards within thedrawings.ISO 128 is aninternational standard which shows the general principles of presentationwithin technical drawings but mainly the graphical representation of objects ontechnical drawings.ISO 1101 is aninternational standard that focuses on geometrical tolerances. Tolerances ofform, orientation, location and run-out. P.2 – Explain whichfeatures of CAD drawings need to comply with national and Internationalstandards.CAD standards are a set of guidelines that all CAD drawingsshould follow to improve the productivity and so the drawings can be copiedinto other CAD programs.
There are a few features within a CAD drawing thatshould all comply with the national and/or international standards:· Text and Dimension· Scales· File naming standardsThese should always comply with the correct standardsbecause they all need to be done to the same standards so that they can all beread correctly and so everyone can understand the drawing. The standard it isdrawn in should be written in the title block of every drawing so that they canbe easily understood and the person using the drawing know which standard toread it in.P.3 – Explain theadvantages, compared to other methods, of producing drawings electronicallyusing a CAD package.There are many advantages of using a CAD package whenproducing electronic drawings.
First of all though, CAD is very important andhas made the storage and retrieval of products and drawings a lot easier asthey are all stored electronically. However, manual drawing is still veryimportant as it provides the basics of how to draw certain types of drawings.There are many advantages of CAD, one is that there is no need for scaling thedrawing as all the drawings are done to the correct size. Also the screendrawing area can be changed size very easily so you can create any sizedrawing. Also when drawing CAD drawings, all the tools are supplied by theprogram. And also using CAD means you will be extremely accurate at all times. Production detail can be extracted straight from the drawingwhich save a lot of time and they are also very accurate.
Another advantage ofusing CAD over manual drawings is that both 2 and 3 dimensional drawings can beproduced very easily. There is a very low chance of losing your drawing as itsaved on your computer and can also be saved in other places like a USB stick.Which also means that all the drawings are stored on the computer on a USBdrive so there is no need for a big folder because it’s all storedelectronically. Dimensioning can be almost automatic on CAD drawings so youwon’t have to measure things individually and writing it in.
Also parts ofdrawings can be saved and copied into other drawings when needed so it savestime and also makes making a product with multiple parts very simple.P.4 – Describe thesoftware and hardware that are required to produce CAD drawings.There are many types of CAD software that you could use.
Itis important when choosing the piece of software that you use that it doeseverything that you would like it to do. For example if you are looking tocreate a wiring drawing then you wouldn’t use Autodesk Inventor as that makes3D and 2D parts. Also a less popular CAD software will have a smaller array oftools and users may be restricted to certain graphics cards etc. An obvious thingto do was to make sure that your computer or device you are using actuallysupports the CAD program you intend to use. If not you may need to update yourhardware or get a supported piece of software.Like I previously said it is important to check thespecifications of your hardware to see whether it is capable of running the CADsoftware you have chosen. If not then you could also find out whether there isa more powerful machine is required in order to run the program you wish touse.
Most CAD software’s are run on Windows PC’s and not Apple Macs or Linuxetc. Also the hardware should have enough RAM to run the software and a bigenough hard drive to hold the program and also any work that you will carry outon the program. If you are making large drawings/models then it will require amuch more powerful computer. However if the drawing contains no 3D sections andis completely 2D then the computer won’t need to be as powerful. If a CADsoftware has a significant update then the specifications of the hardware mayneed to be upgraded in order to run the new and improved program.
The monitor or screen should not be distorted and should beas big as you can afford. This is because a bigger screen will make it easierto see bigger images and also see the smaller details a lot easier. A plotter is used to print the drawingproperly. A good plotter will produce the drawing no matter the size to adecent standard. M.1 – Explain therelationship between CAD and other software/hardware used in manufacturing.