model space

Is there a command that will tell you what scale the model space is in or is it always 1:1?

how to set the model space scale, say to be 1:1 or 1:20, 1:30, etc?

Welcome to CADTutor. When in modelspace EVERYTHING is drawn full size 1:1. In that way this question never need be asked, nor is there any confusion arising from the scale of that which is drawn or created in modelspace. It is what it is. There are drawings done of the entire universe, and they too are done full size. Scaing objects in modelspace just rocks the boat for everybody else who knows better. Scaling should be done through the VIEWPORT in paperspace, where almost everything will be scaled, in order to fit comfortably on the layout and subsequently on the sheet at printing.

Excellently put Dadgad

while Dadgad's advice is perfect for drawings YOU are doing, there is no way of determining what scale a received drawing has been produced at. You need to find a reference (known) size and measure it to calculate the scale.

This week I have been working on a set of drawings where one sheet has been drawn at 80% full size. This actualy caught me out on the next sheet as I put in some components at 80% and fitted better than expected. I check another size only to find this sheet had been produced at 100%. Don't you love consistency.

I'll second that one dbroada. Over the years since layout tabs were first introduced... I think it was R14, anyway, there are still some dinosaurs left around who refuse to make the shift away from everything being done in model space. It is true that you can do anything you want in model space, like draw objects at a different scale and set dimension scale to something else, etc... I always advise detailers to draw 1:1 in model space. Then when you present your drawing using paperspace, and set the scales there. Makes life simple and it's really the true power of CAD systems, not just AutoCAD.

we still use exclusively modelspace - there really is no advantage in paper space for electrical circuits which is 95% of our work. However, we still draw our mechanical items at 100% and scale up the border to fit around the model. All works well enough untill people start drawing things at any other scale than 1:1.

.... there is no way of determining what scale a received drawing has been produced at. You need to find a reference (known) size and measure it to calculate the scale.

Contradictory statements.

Need more information from the OP.

If you are creating the work do it at 1:1 (it does not make sense to scale a border since this doesn't represent real world and is work that does not need to be done).

If you are getting work from someone else, can you attach the file here so that someone can demonstrate with the actual file how the scale would be calculated (and then corrected to 1:1 if needed).

Contradictory statements.

 

Need more information from the OP.

If you are creating the work do it at 1:1 (it does not make sense to scale a border since this doesn't represent real world and is work that does not need to be done).

 

If you are getting work from someone else, can you attach the file here so that someone can demonstrate with the actual file how the scale would be calculated (and then corrected to 1:1 if needed).

i do it quite often, esp with drawings that originated in MicroStation.

often there's something with a dimension on it so you can get a pretty good figure.

other times it's simply a case of measuring a door or something and having an educated guess.