Jump to content
Guest flyingal

understanding drawing scale and scale factor

Recommended Posts

Guest flyingal

Hi:

I am a newbie AutoCADer and am having some problems getting the hang of applying the drawing scale to my assignment. I understand the scale factor that is applicable to the printing only and that AutoCAD doesn't care about the units used...but something is not clicking here and I'm sure it is pretty simple. My assignment requires me to draw 3 simple structures at 1/8" scale on 11X17 paper. Each house is 20' long with 10' walls and each is done in absolute, relative, and polar. I actually completed the work with all 3 formats without specifying the scale or paper size, just to get familiar with the commands. But now that I am trying to set the dimensions correctly, I cannot replicate my work because I'm getting lost in the way things are defined. Any help would be appreciated. I am using AutoCAD 2005, also have a 2002 version to which I can defer.

Thanks everyone!

Share this post


Link to post
Share on other sites
Guest odon

Scale factor (as used by AutoCAD) is always a reciprocal of the drawing scale.

 

AutoCad uses the unit one as the base unit.

 

For example, if you wish to plot a mechanical drawing at a scale of 1/2

Share this post


Link to post
Share on other sites
hendie

why on earth would someone want to "draw to scale" in Autocad ?

surely the whole point about computers/CAD is that we can get away from that old drawback of paper.

In CAD, the space is "infinite", everything should be drawn at 1:1 ~ viewports are where any "scaling" factors should come into play

 

 

 

 

 

 

 

 

 

and here starts another argument :twisted:

Share this post


Link to post
Share on other sites
f700es
why on earth would someone want to "draw to scale" in Autocad ?

surely the whole point about computers/CAD is that we can get away from that old drawback of paper.

In CAD, the space is "infinite", everything should be drawn at 1:1 ~ viewports are where any "scaling" factors should come into play

and here starts another argument :twisted:

 

Read this tripe....

 

http://www.rosegill.com/Bullpen/SoapBox/Illusions.html

 

This is from the owner of Engineered Software, the maker of PowerCADD ( a mac only CAD app.).

 

:roll: :roll: :roll: :roll: :roll:

Share this post


Link to post
Share on other sites
hendie
Read this tripe....

 

I don't think they have a smiley for what I'm feeling after reading that !

Share this post


Link to post
Share on other sites
f700es
Read this tripe....

 

I don't think they have a smiley for what I'm feeling after reading that !

 

Everyone here needs to visit that site and just take a look at the way they act. It's no wonder there anti-apple sites all over the net, with attitudes like that. It just kills me. These users throw off on AutoCAD in about everyother post. They try to make fun of us drawing 1 to 1 yet when a cross platfrom program like VectroWorks or SketchUp draws 1 to 1 it is ok..

major_roll.gif

Got into a internet arguement with one of their users on another forum a couple of years ago after he said that we could not do solid fills, had no accuracy, could not export to illustrator (or anything else for that matter), unstable program and other un-founded remarks. Evern called me a liar when I posted some screen images of things that he said Acad could not do. I'll put Acad up against just about anything.

 

another smily for them...

 

retard.gif

 

F7

Share this post


Link to post
Share on other sites
CADTutor
Read this tripe....

 

http://www.rosegill.com/Bullpen/SoapBox/Illusions.html

 

This is from the owner of Engineered Software, the maker of PowerCADD ( a mac only CAD app.).

 

A joke surely? No one can still hold views like that - at least not if they live in the 21st Century. I have to say that this sort of view is propagated by people who find the transition from drawing board to computer rather confusing. They feel much more comfortable working with an electronic version of their old tried an trusted manual tools. Their loss - new technology means new tools and new tools means new method and new method leads to new opportunities.

 

It's a brave new world but some are just a little bit scared to jump.

Share this post


Link to post
Share on other sites
f700es

David, I wish that was a joke but it is not. Browse through the their/his site and see. http://www.engsw.com

I am also sad to say but these guys are only about an hour away from me here in NC, USA.

Here is their forum...http://powercadd.designcommunity.com/index.php

 

Pretty pathetic to me :evil:

Share this post


Link to post
Share on other sites
gcp310

End of the day you need accuracy,and drawing to scale the old way is just not feasable.

 

Small minded Souls. I love macs for their simplicity, but hate them for the lack of cross platform programs.

 

Tell me, isnt Archicad a 1-1 program?

 

G

Share this post


Link to post
Share on other sites
f700es
End of the day you need accuracy,and drawing to scale the old way is just not feasable.

 

Small minded Souls. I love macs for their simplicity, but hate them for the lack of cross platform programs.

 

Tell me, isnt Archicad a 1-1 program?

 

G

 

Not sure about Archicad but it probably is. Just about every CAD/3D application I can think of does 1:1. To me it is just another example of the "Mac - I'm better than you attitude". I work with 2 mac users and they both have this attitude that since they us macs their designs are automatically better :roll: .

Share this post


Link to post
Share on other sites
Paul Sweet

Don't knock it unless you've tried it. I learned CADD using Generic CAD, just before Autodesk bought it and ran it into the ground. In my last job I used PowerCADD for 4 years. I have been using AutoCAD in my present job for just over a year, and also use Visual CADD (a Windows version of Generic CAD) when I want to draw something quickly.

 

When I am drawing in CAD, I have always thought in full size, whether the program uses a full size model, like Generic CAD or AutoCAD, or is prescaled like PowerCADD. When drawing to scale, you still draw full size, but the computer keeps track of the scale. The main difference is that the scale is set when you start drawing, rather than when you plot. Lettering, dimension arrows, etc., are real-world size, so you don't have to change styles and letter heights. It's something like working in Paperspace, without the complications of setting up viewports, etc.

 

AutoCAD has extra power for large groups working on large projects, but the added complexity that comes from this power often makes doing simple drawings more cumbersome than it needs to be.

 

Flyingal, be sure that scale factors in your dimension definitions are all set to 1, and that units are consistant (there are many places to accidently change these without realizing it). Make sure everything fits into a 88' x 136' rectangle, then set the scale to 1/8" = 1' when you plot.

 

I used to love flying Cherokees and Tomahawks, before I had kids and still had time and money, but I've never flown a Cub. I'll bet it's a lot of fun!

Share this post


Link to post
Share on other sites
f700es
Don't knock it unless you've tried it. I learned CADD using Generic CAD, just before Autodesk bought it and ran it into the ground. In my last job I used PowerCADD for 4 years. I have been using AutoCAD in my present job for just over a year, and also use Visual CADD (a Windows version of Generic CAD) when I want to draw something quickly.

 

When I am drawing in CAD, I have always thought in full size, whether the program uses a full size model, like Generic CAD or AutoCAD, or is prescaled like PowerCADD. When drawing to scale, you still draw full size, but the computer keeps track of the scale. The main difference is that the scale is set when you start drawing, rather than when you plot. Lettering, dimension arrows, etc., are real-world size, so you don't have to change styles and letter heights. It's something like working in Paperspace, without the complications of setting up viewports, etc.

 

AutoCAD has extra power for large groups working on large projects, but the added complexity that comes from this power often makes doing simple drawings more cumbersome than it needs to be.

 

Flyingal, be sure that scale factors in your dimension definitions are all set to 1, and that units are consistant (there are many places to accidently change these without realizing it). Make sure everything fits into a 88' x 136' rectangle, then set the scale to 1/8" = 1' when you plot.

 

I used to love flying Cherokees and Tomahawks, before I had kids and still had time and money, but I've never flown a Cub. I'll bet it's a lot of fun!

 

Played with it several times on the co-workers Macs. I never said PowerCADD was inferior or worse (if so not what I meant). The idea that your designs will be better on a Mac and/or PowerCADD is what I am laughing at. How absurd! They are simply tools used to complete a task. The owner of PowerCADD seems to have a chip on his shoulder with Acad. I see PC as a very powerful Illustrator with drafting tools.

Share this post


Link to post
Share on other sites
mikay

I find the scale problem is closely related to the total lack of dimensions on today's arch drawings related to planning applications - so much so that I'm beginning to believe that unscrupulous firms do it purposefully to obfuscate the planners or lay persons who have a legitimate reason for opposing a planning application but cannot 'read' an arch drg. as currently offered.

 

The Gov's Planning Portal and many LPA's support on line planning apps. and whereas asks the PP requests that drawings should at least bear sufficient dimensions to calculate the volume, LPA's make no such strictures, not even to ask for a scale bar - hence the high number of arguments and strength of ill feeling existing between planners and the public.

 

Perhaps someone can enlighten me. I,for one, can see no reason at all today for not dimensioning all drgs.

 

I confess to have been apprenticed in the old school!

Share this post


Link to post
Share on other sites
cwdesign

I understand how to determine a drawing scale factor, but I can't find where to input the drawing scale factor into AutoCad.

Share this post


Link to post
Share on other sites
Dadgad
I understand how to determine a drawing scale factor, but I can't find where to input the drawing scale factor into AutoCad.

 

Welcome to the forum. :)

 

When you are working in modelspace everything should be drawn full size, 1:1, with no scaling.

Scale doesn't come into play until you start working in VIEWPORTS.

Remember that a viewport is essentially a translucent window through your sheet of paper,

to the DRAWING which should be full scale in modelspace behind.

No matter what you are drawing up to and including the solar system and beyond, you do it full size.

Given that, it is more than likely that you will typically have to scale the view shown through

your viewport to fit what you want to show in the viewport on your printed file.

You can set the scale of a viewport by selecting it in paperspace, and adjusting the scale in the PROPERTIES or the QUICK PROPERTIES palette.

If you have the VIEWPORT SCALE enabled in the lower right hand corner of your screen you can also change it there.

There is also an icon available there to lock or unlock the viewport.

Once you have adjusted it to display what, how (visualstyle), and at the scale you want LOCK the viewport, so that it can not be

inadvertently changed while you or someone else is working with or on the drawing.

 

If you look at the image you will see all of the relevant information regarding

the selected viewport displayed in my QUICK PROPERTIES palette, and you will see

the viewport scale and lock icons circled in red.

 

You can have lots of different viewports on a sheet, and each may display different perspective, visual styles, layer visibility states and scales.

A viewport should always be created on a dedicated layer ( I use Mview) , and that layer should be set as nonprinting.

Double clicking inside of a viewport will take you through the window to modelspace (although it will display a white background, or at least the same color as your paperspace), but you are

really in MODELSPACE, and so can work with any entities which are there. If you want to you can also use the MAXIMIZE VIEWPORT button to enter MODELSPACE and see it,

with the default color or whatever custom color you might have changed it to in your OPTIONS.

 

When you are setting up your viewport layout there is no need to unlock it, if for instance your scale is already

determined and set.

If you are double clicked into your viewport you can move things around in modelspace without

unlocking your viewport, which means that your scale is not affected, and you can lay everything out as you want it to appear on your printed drawing.

 

To cycle through available viewports on a sheet double click into any of them,

then use CTRL+R to switch from one to another.

viewport basics.JPG

beam me up viewport maximize.JPG

Edited by Dadgad

Share this post


Link to post
Share on other sites
cwdesign

Thanks for the welcome and answer Dadgad. :)

 

 

 

 

We don't seem to be on the same page about the intent of my question. I am asking about the drawing scale factor rather than a drawing scale.

 

 

The scale factor of a drawing should be determined and utilized during the time of drawing set up.

The proper scale factor is extremely important because it makes sure that text (height, etc.), dimension values (dimscale), hatch patterns, limits, and linetype scale (ltscale) are plotted at the proper size.

 

I need to find where I put in the drawing scale factor which will adjust the objects mentioned in the above quote.

Share this post


Link to post
Share on other sites
ReMark

Are you using a paper space layout with at least one viewport? Yes or no?

Share this post


Link to post
Share on other sites
cwdesign

No. I'm just working in model space for now.

Share this post


Link to post
Share on other sites
ReMark

What are you doing that you are being prompted for a scale factor?

 

BTW...do you intend on making use of Annotative scaling for your text and dimensions?

Share this post


Link to post
Share on other sites
cwdesign

Setting a drawing scale factor is part of setting up a drawing. Without the drawing scale factor set, I will not be able to read the dimensions and text - they will be too small on the screen. I would have to define text height in feet. Then, when I do want to plot, the text would not plot correctly.

 

I am not 100% sure how to answer your second question. I need to review the workings of annotative scaling.

I'm thinking that annotative scaling will adjust the text and dims if I change scales, but I believe that I still have to define a drawing scale factor when I set up the drawing.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×