Changing units midway through a drawing

[nor.mahn]

I'm practising drawing a window and have the units set to inches. I've drawn most of it in inches,  but there are few areas where I'd like to offset lines in centimeters. Is it possible to do this? Can I offset a line in x centimeters when the default drawing units are inches? I don't want to do it converting centimeters to inches. What's the procedure for this?

[tramber]

I am afraid there is none.

But you can draw in another drawing using millimeters by declaring it in the UNITS box.

And then insert it in your target drawing, wich has been set correctly (inches) in the same box.

The process should automate the scaling.

If not, just consider that the space you use has no unity and that you can't change the scale of your actions, only the scale of objects.

[LyleHardin]

It's not as easy in AutoCAD as it is in Revit, but you can do the calculation on the fly.

When asked for the offset distance, you can type in a simple LISP formula.

(/ dist 2.54)

where dist = your centimeter distance you want to offset.

This will feed the result (calculation) back to the offset command.

For instance if you want to offset 5 cm, then your command line would look like this:

Specify offset distance or [Through/Erase/Layer] <0'-1 31/32">: (/ 5 2.54)
1.9685

Not great, but it beats using a separate calculator or scaling things.

Here's a LISP routine I made eons ago when we were working on a metric job.

This turns Inches to Millimeters, but you can change the values to work the other way.

;;; offsets by entry/25.4 converting mm to inches

(defun c:offsetmm (/)
(setq mult 25.4
dist (getdist "Enter Offset distance in Inches to convert to Millimeters")
dist (* dist mult)
) ;setq
(command "offset" dist)
) ;defun

[nor.mahn]

It's possible in Revit then? 

[Kent1Cooper]

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@nor.mahn wrote:

.... I don't want to do it converting centimeters to inches. What's the procedure for this?

---

Welcome to these Forums!

You don't need to convert yourself and then use the converted value in an Offset command.  You don't even need to know how many centimeters there are in an inch, nor what to divide by or multiply by what to get the right result.  Assuming you're not using AutoCAD LT, you can have AutoLisp do the conversion for you, and all you need to know is the centimeter(s) value you want used.  At Offset's distance prompt, do this:

(cvunit x "cm" "inch")

with x being your centimeter(s) value.  It will return the equivalent distance in inches for Offset to use.

[LyleHardin]

Yes. Even if your Revit model is set to Inches or Feet, or whatever, you can just type in 5cm or 50mm for your move/copy/offset distance and Revit will convert it for you. It's pretty slick.