units and numerical defined object sizes

hi list, I’m new to blender and this my first post, so please be patient :wink: . I doing my first steps with blender (last version on linux), so after playing around awile I have some questions which I would like to post here.

I want to use bleder to model (relativly simple) object that at the end sould exported as dxf and be fabricated on a 2d lasercuter, so to my questions.
I do know how to align object an vertex to grid and to change the grid with the zoom. But what are the units? It is possible to aply units like mm to the (I guess) relative units in blender? Then If I want to build a object (rectangle) with the exact side-rato of 2:1.15 how do I do that? Or I would like to built objects with the sizes 2, 2.15, 3.45
And somthing about importing, I try to import paths made with inkscape (linux) thes seams not to work, error or produces faulty paths in blender. Do I somthing wrong or is this a bug. How could I avoid that?

thanks for enlightenment
noskule

I’m no expert in this part of blender, but there is a collection of nice links concerning a similar topic - Blender in architecture:

http://mediawiki.blender.org/index.php/Architecture
Edit: Especially Modeling Tutorial Using Inkscape And Blender might help you.

I general: Blender uses the ‘dimension’ you want it to use (similar to e.g autocad). The easiest way to imagine that is to define for yourself that 1 Blender unit equals e.g. 1 Meter. I’ll leave rest to other people with more knowledge in this area :wink:

Werner

Firstly, forget using blender as a cad tool. It just isnt and doesnt work with the kind of dimentioning you probably need. I assume your profile cutting (I used to do air-plasma sheet metal profile cutting) If your doing 2d cutting then just stick to svg or other 2d format. You can export in dxf from coreldraw…

IMSI makes a low cost CAD program called TurboCAD Deluxe, about $40, that would probably work better for you. But any program that does vector drawing may work also.

Oky I see, I will check the tut in the wiki, thanks Hoehrer. I thought that I could do animations of the things to explain functionality in the same tool as actualiy developing it. But I now guess it is a better choise to use a cad soft to develop the things and then import it to blender. Does anyone have good exirience with a cad soft under linux?
thanks nos