Cad standards documentation

Documenting what you have for CAD standards is key for two reasons: 1.) It allows the users to be able to look up the settings and data used previously, and 2.) It allows the CAD Manager to keep track of what he/she has and how it was set up. Believe me, as time goes on, aside from the everyday tasks you do, it is easy to forget what, where and how your drawings were originally set up. This again supports my main point that you should be writing CAD standards for whatever you are using, whether it is AutoCAD, Revit, Inventor, SolidWorks, etc.

When documenting CAD standards you really need to keep it as simple as possible. Anything long winded or difficult to find will not be read and most likely not followed. For example, when creating the templates, all you want to do is list what’s inside each template and its intended use. I like to put the template’s intended use on top because that is usually all the user will need to know. The remaining content within the template is necessary for the CAD Manager in order to keep track of what they have and how it was set up.


How you document your CAD standards is key if you want the documentation to be read and used to increase efficiencies within your CAD department. I would dare say that over 90 percent of the CAD managers put their documentation in a number of Word and/or PDF files and place them in a folder ‘somewhere’ they hope will be found when needed. Another ineffective means for CAD standards documentation I’ve seen includes creating html's as well as the use of hyperlinks to extensive user guides. Even though it is important to document your CAD standards, I really feel when ineffective documentation is used, especially when you include user guides into the mix, the CAD standards will not get read and will collect dust. Also, searching through files in order to find the page with the information needed to comply with a CAD standard becomes a time consuming and non user-friendly chore that they will quit doing.

What I have found useful is to create a help file (CHM file) that is indexed and searchable as almost everyone has used them or at least seen them since practically all the software you purchase for use on the computer comes with a help file (CHM file), including Autodesk and Microsoft. Once the CHM file has been created I like to place it where Autodesk has placed theirs in the menu system to increase the potential for usage. In case you were wondering how to create a CHM file, Microsoft has a free downloadable application that allows you to put together and compile a CHM file. I feel the need to mention there is a slight learning curve when using this application, however, this will be offset by creating something that is more user friendly, resulting with effective CAD standards documentation that will more likely be used by the end users.


CAD Standards can be as simple or as complicated as you want them to be. There is no basic template available to follow; however, I encourage you to set up a template for use in your CAD department. The most important point I want to emphasize is to take what you have for CAD standards, get it down in writing and make it as user friendly as possible.

Cad Standards - Templates

I am starting a new blog that will talk about CAD standards. In the discussion groups found on the web I’ve seen questions range from “How you do you create CAD standards?” to “How do you document them?” Of course, you have each discipline and company bringing their own flavors into the mix. To me, the most important part of CAD standards is consistency - without consistency you drive down productivity and drive up costs in addition to creating drawings that are prone to errors.


I would like to begin by talking about the value of templates. Templates (dwt) are merely drawings with another extension that are used to start new drawings without having to recreate the same settings each time. Just like everything else in CAD, you can set up your templates with whatever data you would like - just be consistent! For example, you may want to setup your template with the Title Block in mind, using A, B, C, D, etc...., which happens to be a very popular method used, especially when you create a new layout within paper space when asked from the template.

One method I like to use as a CAD standard is to have a general setup that is common between all drawing sizes, such as layers, line types, dim styles, font styles, units, drawing properties, etc... which will allow you to start creating your model. Another reason I do this, is to create a backup in case you lose any of your settings during the course of the drawing – such as thru a purge. I have the template saved as a drawing file that I can just insert and get any of the settings that might have been lost resulting from a purge.

You may ask, ‘Why have a dwg and dwt file that are the same?’ As I mentioned previously about being able to use the dwg to retain anything lost – it is also important to state that I always make changes to the dwg file and save it as a template. I also like to have templates that are geared towards the paper space layouts and contain the title blocks as well as any special items that are geared towards the use of the paper space tabs. To be honest, I have always viewed paper space as a means to print out what you have, so the only work I do in paper space is the title block data. Now this will probably spark a controversy, which is ok. Another timesaving item to keep in mind regarding the template is if the setup has been done correctly, you will never have to go into the paper space items for anything; this includes sheet numbering or filling out the data in the title block.


In conclusion, I believe when creating CAD standards you need to sit down and determine how you want to use them – which in turn, will help you determine what you put into your CAD standards. I also want to emphasize that templates and the need for consistency are essential in the development of CAD standards which result in productivity that is effective and efficient.

Patrick K Johnson

Dictionaries inside AutoCad

I am writing this blog on Dictionaries inside AutoCAD as follow-up to my last blog posting defining Xrecords inside AutoCAD. Dictionaries are containers in essence, that by themselves do not hold the data you intend to store and retrieve. They hold a variety of other objects that contain the data; Xrecords for example. Dictionaries can also contain other dictionaries; basically you can nest the dictionaries. Using dictionary and Xrecords is a means to store data that has no graphical representation - a means to what I call creating a smart drawing. You can store data for variables, create parametric drawings, store selection sets, etc.... Since the data is stored when you save the drawing, anything you store will be available the next time you open the drawing. To me the limiting factor is your imagination.

There are 2 types of dictionaries I am going to talk about, one being the Named Object Dictionary (NOD) and the other is an Extension Dictionaries.

NOD
This dictionary is the parent dictionary that owns all other dictionaries. This is where you should place data for the entire drawing so you can gain access to it at any time during your programming and know that it is drawing specific - I refer to this as global access. This dictionary will always be preset in the database. Since AutoCAD uses this dictionary for items such as mlines, you do not want to store your Xrecords directly into the NOD. You will want to create a dictionary that is specific to you inside the NOD where you will store your Xrecords. I believe this helps to organize your data more efficiently.

Extension Dictionary
This dictionary is nothing more than a dictionary that attaches to entities that store Xrecords which are entity specific. There is a lot you can do that is entity specific, such as point to other entities or possibly create entity specific standards. Here is an example of how I’ve seen an extension dictionary used: Consider you are working on a drawing in English and it needs to be read in both Spanish and English. You can merely attach an extension dictionary to the text entities that can hold both English text and the Spanish text and have the drawing update to either version. Of course, there is more involved to this process than just adding the extension dictionary – but the intention of the example is to help clarify how an extension dictionary can be used effectively.Hopefully this information helps to explain what dictionaries are and how you can use them with Xrecords to expand the ability of a drawing.

In the near future I will be sharing code examples to show you how to get at dictionaries, add dictionaries, add Xrecords, etc...

To share your comments and questions, please contact me or respond to this blog.

Patrick Johnson

Xrecords - what are they

I have been surprised by the number of people who have no idea what I am talking about when I mention Xrecords. For that reason I am taking this opportunity to explain what Xrecords are.

The first thing we need to acknowledge is that an AutoCAD drawing is not only a drawing but it is also a database with graphical representation. For this blog topic we are going to talk about the database side of AutoCAD drawings.

Xrecords are a means to store data within the database of the drawing using group codes. In short, Xrecords are data containers that have no graphical representation. Xrecords can hold any data you desire and makes use of the same group code numbering system as the AutoCAD objects (lines, circles, etc...). This data can be as simple as a layer name to a class object that is serialized and streamed into an Xrecord. One common practice I like is to use Xrecords as a means to store variables such as width, height and length of an object and use it in equations within a program. The class object is quite powerful as it allows you to use the data within the Xrecord at anytime in your program such as for engineering calculations for a drawing that can be connected to a third party application.

Xrecords are created in two arrays, one being the group codes and the other the data itself. The size capacity for an Xrecord is huge. Xrecords are placed in dictionaries which, in turn, can be stored within the overall drawing file or attached to an entity. (Dictionaries and xdata are two items we will discuss in greater detail at another time.) It is important to note you cannot gain access to Xrecords from standard ‘out of the box’ commands in AutoCAD. Access to Xrecords requires programming ability.

When it comes to the use of Xrecords your imagination is your only constraint.

Please contact me or respond to this blog to share your comments and questions.

Patrick Johnson