Units change from Unitless

[User2012]

I got a unitless model! So, I changed it to Inches (Format/ Units). However, it does sound like nothing has been changed! Any suggestions!

[Dadgad]

A unitless model's drawing data units will be millimeters (I believe).
It will not scale when inserted into a new drawing because it is defined as unitless.
Treating it as if it was in mms, you need to scale it up by 25.4.
You should also open it in the block editor and change the units in PROPERTIES to INCHES.
In that way in the future it will scale appropriately upon insertion into another drawing,
assuming that the new drawing has the insertion units and target units set properly.

[eldon]

A unitless model's drawing units will be millimeters (I believe).

The units could be Light Years. There is no compunction to be millimetres

[Dadgad]

The units could be Light Years. There is no compunction to be millimetres

In my case they are millimeters, but I always use ISO templates.
How would you go about determining that then?

When I use the -DWGUNITS command these are the only options that i get

Command: -DWGUNITS

Drawing units:
1. Inches
2. Feet
3. Millimeters
4. Centimeters
5. Decimeters
6. Meters

......no mention of anything terribly out of the ordinary, or should I say Cosmic?

[eldon]

In my case they are millimeters, but I always use ISO templates.
How would you go about determining that then?

I would examine what was drawn to see if any units made sense.

Also a good start is to see what the MEASUREMENT system variable is set to.

Just because you use ISO templates, there is a large world out there who do not.

[Dadgad]

I would examine what was drawn to see if any units made sense.

Also a good start is to see what the MEASUREMENT system variable is set to.

Just because you use ISO templates, there is a large world out there who do not.

I should think that there must be a non-deductive way to answer such a query?
Assume that you received a drawing with no dimensions, how would you handle it then?
Just trying to make some sense of this.

[eldon]

I should think that there must be a non-deductive way to answer such a query?

I do not do "non-deductive". I regard it as a challenge.

But for non-deductive ways, speak to the supplier of the drawing.

[Dadgad]

I would examine what was drawn to see if any units made sense.

Also a good start is to see what the MEASUREMENT system variable is set to.

Just because you use ISO templates, there is a large world out there who do not.

eldon, you've done it again, taught me something new.
I've never heard of the MEASUREMENT system variable, which really surprises me,
as I have spent a fair amount of time in the SYSVDLG box.
I previously thought that there was no way to change the DEFAULT SCALE LIST on the USER PREFERENCES
tab in OPTIONS, from METRIC to IMPERIAL without changing the template or using the -DWGUNITS command.
I am glad to see that there is.
Thanks!

[SLW210]

What in the world is an unitless model? I never heard of such an object, please post an example.

Insertion Scale Units have nothing to do with the model you have drawn, clearly stated in your images of the dialog box...Insertion Scale>Units to scale INSERTED content:

MEASUREINIT
Controls whether a drawing you start from scratch uses imperial or metric default settings.

MEASUREMENT
Controls whether the current drawing uses imperial or metric hatch pattern and linetype files.

-DWGUNITS is how you should change a current drawing.

[User2012]

Thanks a lot for your comments!
Frankly, I don't understand why the CAD drafter of this model, who has been working for an American company for years, didn't set units to the Inche! Anyway, because this model is the part of a patent design, I have not been allowed to share!
I just drew sth simple in the environment of the model to show you how the measurements look like (Probably mm)! Meanwhile, I have tried DWGUNITS command, but it was an Unknown Command in my autocad program(See dwg file)!
Sorry for being thick!