Basic scaling - drawing in meters, am I doing something wrong?

[Jonathan Pitt]

Hi all, this is probably really basic, but it is driving me mad at the moment.

I have been sent a drawing of a ship, (an aircraft carrier if you are interested?) which has been drawn in meters.

When I then create a viewport in my layout using an A0 border, I would then expect, at 1:1 scale the ship to be massive and I would then have to use a scale of 1:50 or what ever to bring sections of it back into a useable/viewable area, correct?

Problem is, at 1:1 I can see pretty much the whole of the ships layout in an A0 paper size, bearing in mind the ship is 300 meters long and has 9 decks it is quite sizeable. It feels like Autocad thinks 1 meter is infact 1 millimeter.

I have played about with the units in the format menu, but this doesn't seem to make any difference?

Am I just being a complete idiot and making some sort of assumption that is completely wrong? Or is there a simple setting that I need to change?

I'm using AutoCAD 2008 LT (Yep, I know this isn't the LT forum, but I get a better response in this area so hoping you guys and gals will be able to help me.)

Cheers in advance.
Jonathan.

[jaberwok]

Are you opening the file that was sent to you or are you inserting or xreffing it into your own template or border file?
If inserted or xreffed, what is the the value of INSUNITS?

[Jonathan Pitt]

Just opening their drawing, and then inserted my border into the layout. (They hadn't used the layout before as it appears they only worked in model space.)

Unfortunately my company wasn't very proffessional when it came to CAD and we don't have any templates or anything like that. Before I arrived the borders weren't even set to use our plotter! It really is something I need to set up, just haven't found the time yet.

Also never having had any formal AutoCAD training all my knowledge of the program is stuff I have picked up as I have gone along.

Anyway, I digress. The insunits for the original drawing is 6, and for my border it is 4.

This command is new to me so done a quick google search and looks like something I really need to get my head round!

[jaberwok]

Okay, their drawing controls it so you are working in metres (INSUNITS=6).

[jaberwok]

If your border is drawn in paperspace and you want to work in mm, INSERT their drawing into modelspace in your drawing.

[Jonathan Pitt]

Ok, cheers John, so am I wrong to assume that at 1:1 scale in layout space the ship should appear massive compared to the A0 border size, rather than really small as it does now?

Is the title block I am inserting being affected by this insunits setting?

Sorry for asking what probably are really basic questions!!!

edit - you posted while I was typing, my border is drawn in model space...typical!!

I suppose I could just start a new drawing, insert my border, then insert their drawing?

[Jonathan Pitt]

Sorted, thats got it, nice one cheers John.

So that is something I need to look out for in the future then, all these really basic commands that I don't know of that make working with autocad that much easier lol.

This place is great :-)

[Jonathan Pitt]

ok, so I've hit a wall again.

Inserting as a block of the original drawing worked, but if I insert as an xref it didn't? Should it?

Scrub that....I'd somehow managed to set the insunits to 4 in the original drawing....d'oh!!!

[jaberwok]

If you want drawings to behave as YOU want, create a file with all your settings (you don't have to save it as a template file, just as a drawing will do) and insert your received file(s) into that and save it to your filename. That way, all your settings override settings in the incoming file.

[scott.wilcox]

Check the value of the following:

INSUNITS
INSUNITSDEFSOURCE
INSUNITSDEFTARGET
-DWGUNITS

That last one will still scale drawings upon insertion, even if all the others are set to unitless, so check it out.

[irneb]

The underlying problem here is that the PS scales are not affected by the drawing's units. The 1:1 scale (e.g.) simply states 1 MS unit = 1 PS unit (whatever the unit may be).

So if you've drawn the layout title block in mm but the MS is in m, then the 1:1 scale is effectively the same as 1:1000. If you've drawn the PS layout in m however ... it would "look" correct in ACad, but you'll need to plot it @ 1:1000 to not find just a small dot on the paper :mrgreen:

Another solution is to modify the scale list's values. Type SCALELISTEDIT and click Edit for each of the scales you're going to use. Then add 3 zero's to the Drawing units value of each (i.e. multiply by 1000). Note you can't edit a scale's values if it's used already.

The simplest solution is as jaberwok's explained previously. Insert / XAttach the DWG drawn in m into a new DWG's MS. You need to play with the sysvars scott's mentioned to get the scaling automatic ... otherwise you could manually scale the block / xref after placing / using properties / scale command. If you wanted it as a live drawing you could explode after the insert (and scale if needed).