AutoCAD scaling help??

[andrewrae]

Hi all!

 

Having a bit of trouble with something I thought would be basic in CAD!

 

I'm going to do some freelance visualisation work and the architects have supplied me with plans (PDF and DWG), some elevations are at a scale 1:200@A1 others are 1:100/1:75/1:50 etc.

 

How do I convert or scale these drawings back to true size 1:1 so I can take the splines over to 3DS Max to speedup my workflow?

 

Am I missing something simple here? I tried selecting and scaling x75/x50/x100 etc but nothing matches up with the dimensions given!

 

Fairly advanced with the workflows of Max and Maya as an animation graduate but new to AutoCAD!

 

Any help would be immensely appreciated

 

Kind regards,

 

Andy

[blank...]

I'm going to do some freelance visualisation work and the architects have supplied me with plans (PDF and DWG), some elevations are at a scale 1:200@A1 others are 1:100/1:75/1:50 etc.

 

Are you saying they draw in scale? As in 1:100, and 1:50, not 1:1? They actually draw lines that have the length that is to be printed, not the actual length of the object? If that is true you definitely have some material for that thread about crappy CAD drawings

 

How do I convert or scale these drawings back to true size 1:1 so I can take the splines over to 3DS Max to speedup my workflow?

If you don't want to use math, and providing there are some dimensions on those drawings (damn, how do they dimension things if they don't draw 1:1, those dimension styles must be absolute horror), you can use AutoCADs SCALE command, and it's REFERENCE option. Draw a line in 1:1 and use it as a reference to scale everything.

[laszloadrian]

Scale> Reference is the solution.

 

1 Open your dwg and save as- so you do not mess up the original

2 go in MODEL space Delete all the stuff you do not need from the drawing

3 Look for a known dimension on the drawing. (A wall, a door, an opening, anything. Preferably along the Ox or Oy axis, ortogonal direction.) Let's call this AB line. Where A and B are the two ends of the known dimension.

4 If your AB line is along the Ox or Oy axis activate ORTHO mode by pressing F8. this will allow you to draw only along ox and oy axis

5 Now draw a line to the lenght that is called out in a drawing along AB line. This will be line AC and it will be to scale (Example: your drawings call the AB dimension to be 24". draw the AC line to 24" length). Activate the snaps too by hitting F3

6 type SCALE

7 select all your objects that you want scaled (should be all because you deleted all the things you do not need)

8 select as base point the point A

9 now hit R for reference

10 Reference lenght - click on point A and then on point B on your known dimension

11 For new length now click on point C

 

That's it

 

double check with

'_dist

command

Edited February 28, 2014 by laszloadrian

[andrewrae]

Hey guys!

 

Thanks for the great responses!

 

I already managed to get the drawings fixed to what I needed, and I done with the scale>reference command you's were right

 

I think what the architect must have done was use true sizes in model space, then scaled it down, then moved it over to the layout space or something, pretty weird! But it's fixed now and I'm working away with perfect scaled references in 3DS Max

 

Cheers,

Andy

[antwoinegilbert]

I'm having scaling problem as well I keep getting this message

 

3ds Max cannot determine the size, the field shows “(Drawing Extents Not Known)”.

 

This is keeping me from being able to scale my drawing correctly. Also my extrude command makes 10' look like 3 inches when I extrude edible splines why would my scaling be so bad?