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Import trouble with dxf's and VW exports

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Here is the perfect example of why VW exports cannot be directly used for CNC toolpath imports.

I just generated a curved object this morning that is approx. 69" x 150". It was saved as a dxf and I tried

to import it into VW. No go , no way! The object always imports as 2"+ x 5"+ and I cannot get it to

change to the correct size anyway. I have played with import scale and nothing changes. The object was created

in VW, imported to Rhino for fine tuning and then saved as a dxf out of Rhino. It will import correctly in

AutoCad 2004 without a problem and also back into Rhino, but it will not import correctly back into VW.

This is very troubling to and exactly why I recommended NOT using VW exports for direct import into

CNC toolpathing software. This is exactly why I imported it into Rhino first. The VW exports cannot be trusted

as far as I am concerned. This is an item that NNA should look at and resolve.

Thanks,

Tom in PA

WinXP

VW 11.5.1

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Could you, please, send both original VW file and the DXF you are trying to import directly to me (nivanova@nemetschek.bg)?

Thanks,

Nina Ivanova

Software Development

Nemetschek

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Tom,

Thanks for the files - they really cleared the situation.

As I understand, you export from VW, import the DXF in Rhino, do something there, export it as DXF and after that import the resultant file in VW. This is very long way hence there are multiple places where things could go wrong.

Your original .mcd document uses Feet&Inches and when you export it as a DWG/DXF, your AutoCAD drawing will be in Inches. If you now import back just exported DXF in a blank document with units set to Feet&Inches, you will see in the Import option dialog that Model Space Units in the file are Inches - check that Determine Automatically shows: 1 DXF Unit = 1". Finish import and compare both original document and just imported document - you will see that both docs are identical:

- Objects are with same sizes;

- Line Style applied to 2 of the objects in the original document is preserved and corresponding imported objects are drawn with proper line style;

- There is no missing objects;

- Notice the high quality of the imported objects.

I opened in AutoCAD the DXF file which you have exported from Rhino and checked for Units - they are set to millimeters - your drawing is already approx. 160mm x 320mm in size (compared to 160" x 320" in the original file). This change could happen on Rhino dxf import, on Rhino dxf export, or inside Rhino. I also noticed these changes:

- Line Style is lost;

- Quality of the Oval object is lost;

- Some objects use Color 255, which is seen inside AutoCAD as White on black background and

as Light-gray on white background (instead of Color White).

If you now import in VW the Rhino's DXF in a blank document with units set to Feet&Inches in the Import options dialog you will see:

Units Setting In File: Millimeters

Determine Automatically: 25.4 DXF Units = 1".

If you confirm these settings, your 160mm x 320mm drawing will become approx. 6" x 12" which is absolutely correct.

VW can help you to receive your drawing in its original size: Knowing that the dxf has been saved by Rhino in millimeters instead of inches in the Import options dialog you could change Units: Determine Automatically to Inches - in this way you will have 1 DXF Unit = 1". Import and see that the size is same as in the original file.

Note also that there is no missing objects - there are some objects drawn with White color - VW always import Color 255 to White and exports White to Color 255. You could use Set Colors to Black and White import option to check that all the objects are imported.

HTH

Best regards,

Nina Ivanova

Software Development

Nemetschek

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Nina,

Thanks for the input and evaluation of the problem.

The import white may explain the missing parts. I have never had a problem with units until now, or at least I did not understand the whole situation.

I will play around with this file today.

I normally do use AutoCad its just there because of all the files we receive. We export to Rhino for final changes that are cumbersome in VW and then we output to CNC software from there. The import to Rhino is where we find the most problems. Export from rhino has always been in millimeters and has never posed a problem before.

The re-import into VW is just a wierd case itself.

I will keep you posted of any other problems.

Thanks again,

Tom in PA

WinXP

VW11.5.1

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