Dimensioning in paperspace 1

[dozer]

We've got a new guy and he has a practice that is new to me. I'm looking for some opinions.

He actually dimensions parts right in paperspace. What he does is make a dimension style that scales the dimension according to the scale of the paperspace. Let me illustrate since that description is probably confusing. Say the paperspace scale is 3/16" = 1' ie(1/64). Then he would use a 64 multiplier on the dimension annotation.

My initial reaction was don't do this. Dimension stuff in model space. But then I got to thinking at least you could do transparent zooms while dimensioning. I'm still not convinced it's a good practice, for one thing it introduces the possibility of human error. Suppose the user thinks he's got 1/64 paperspace but he really has 1/65, too small a difference to notice if you're just flying along trusting the numbers popping out.

Anyway, I don't want to be accused of being inflexible so I would like some feedback on what some of you think about this practice.

Thanks

 

"R"
Actually, most AutoCAD standards advocate annotating dimensioning in "paper space". Some call these standards or refer to these "good CAD practices".

The only initial problems I see with this is modifying details tends to be tricky.

One:
Do you activate the floating viewprt and make the modification while in paper space and risk the chance of messing up the zoom factor.
Two:
Or do you totally switch to model space and hope that the CAD users doesn't forget to modify every dimension string in paper space.
Three:
What about standard blocks for your library? From time to time details will be developed in which you feel would make a good addition to your library. Now the annoatation and dims need to be moved to model space and scaled to the appropriate scale and adjusted to the detail again.
Four:
This is really not a complaint but the CAD user must know how to maintian his many dim styles and where to modify the multiplier. Although you run into this when you just do you dims in model space, so this really can't count.

The only thing I see as a good thing is...
One:
For plans when referencing the annotation and dims won't be seen becuase "paper space" items can't be "xref'd". One less step for others to do when composing their drawings.
Two:
One or two text heights are only required to be remembered. 3/32 and 3/16 OR 1/8 and 1/4 depending on your office standards. Factors for different dim style is still a list of numbers, but the only list of numbers to remember.

I do it in maodel but others here vary with personalities. I can work it both ways. But it requires me to train everyone who comes in to know both ways so there are no surprises when drafting with each others files.

These are my thoughts ....

 

[butelja]

If you are working in 3D and using the SOLVIEW, SOLDRAW, and SOLPROF commands to generate your 2D views, dimensioning in paperspace is the only way to go. It is a nightmare in 3D to acually dimension in modelspace and have the right dimensions show only in the right paperspace viewports.

For strictly 2D work, it is less common. I tend to agree that it is not good 2D practice. There is more room for error, particularly when you have different details shown at different scales.

 

[ADMIRALKEN]

In the newer versions of Autocad you can select "scale to paper space in your dimension format. I do this all the time. Then if you change your paper space scaling, the dimensions update automatically.

 

I don't suggest you to use dimensions in the paper space you can spend a lot of time waiting for your computer to switch from PS to MS and viceversa if your are at the same time updating your drawing.
I use paperspace all the time but my dims are in the model with different dimstyles. So, if I have to resize a viewport in paper space, I just change the dimstyle of the dims included in it. Then I'll always have the same text high, arrow size, etc. in my hard copy.
Just remember to Lock your viewports once you have them set up.
The only "good reason" you have to use dims on PS is when you have a huge drawing as a Xref wich somebody else in working on and you have different people drawing small portions or details of it at the same time.

 

[Striker]

Dimensions in PS can be fine provided they are done at the end of a project. Even Autodesk, when they designed the ADT package, made the dimensions to go to model space. Associative dimensions also only work while in the same space as the object.

 

[dozer]

Thanks for the input everyone. After reading your comments and polling some other folks, I'm going to stick with my original thought which is, as a rule of thumb, on 2D drawings, dimension in model space.

 

[Flareman]

rkillian
I realize that you've basically closed off this discussion, but it seems to me that THE WHOLE POINT of paperspace is to facilitate a good paper presentation with a consistent and matching dimension style. When you dimension in model space it forces you to scale all the dimensions and text so that letters are 6 ft high. Then when you open another window as a detail off the same model in a different scale you get all the odd sized dimensions and you have to mess around with layers on and off etc. and two sets of dimensions on the model. Open the window and set the scale then dimension in PS. Every detail on the drawing then has the same dimensioned appearance.
If you don't do that, why on earth are you even in PS in the first place?
I hate to say this in the face of such a lot of people clearly still dimensioning in MS but the word Dinosaur comes to mind.
Sorry guys but I'm with the new chap (he's not only new he's up-to-date!!)

 

[cfee]

The last post is exactly right. Managing Dimensions in MS can be a nightmare! PS dims CAN be associative in the sense that they can be snapped to object snaps (I refer to this not as associative, but that the dims can be "associaTED&quot and if associated correctly with the scale of the viewport, can be managed with much more consistency with far less overall effort. While its not true associativity (redesigning a detail...) many of the benefits of associativity remain useful when dimensioning in PS. On the zooming question, I created a small set of zooming buttons that took me to PS first, so I wouldn't have to deal with re-registering a detail with its dimensions if I forgot. But other than that, associating the dimscale with PS scale factor (as in a previous post) and some of the other tips given make managing dims in PS much more convenient. Remember-there is really no good excuse for not mastering scales in AutoCAD. The comments on 3D work were especially appropriate.
GOOD LUCK!

 

[jugglerbri]

A couple suggestions, if you do dimension in paperspace (which I don't recommend) lock your viewports (either through the properties window or the command mview->lock). This way, you don't have to worry about accidentally panning or zooming in the viewport.

Another thought would be to use a standard dimensioning style that is not scaled at all (this way you don't have to worry about the scale of the drawing), set the dimscale to 0 (yes, I said 0), and dimension THROUGH the viewport. This is the same as dimensioning in model space with the dimscale set the same as the scale in the viewport.

Brian

 

[jugglerbri]

Oh, I want to add that I'm a civil engineer so most of our drawings have only one viewport for each area so I don't have to worry about dimensions overlapping.

Brian

 

[cadkid]

I just have to jump in here and say that dimensioning in PS is considered good cad practice. Yes if you only use one view port you may not see the need, but once you add a second that's where you will see the usefulness. And as butelja said if you are dimensioning 3D it's the only way to go.