Illustrator SVG export opening offsize in Sheetcam and CorelDraw

[motoguy]

A customer has been sending his drawings over in SVG format, so I can directly import into Sheetcam. Unfortunately, the drawing is importing at weird dimensions. In Corel, it's coming it 185% oversize. Ie, it's supposed to be 12" wide, and it's importing as 22.154" wide. In Sheetcam, it's coming in UNDERSIZE: 9.6" (80%) This size issue occurs in both Sheetcam and CorelDraw. When I visit this site:

http://forums.autodesk.com/t5/design-va ... 561#M34020

I see that SVG can be exported in what seems to be unexpected formats:

"One thing to remember is that many SVG tools output the SVG in PPI not in imperial or metric units.
So when inserting the SVG into a mm document you need to scale by 0.35277777777778

Why .35....
72 PPI = 1inch
72/25.4 = 2.8346456693
The reciprocal of 2.8346456693 = 0.35277777777778
I keep this value handy so as I bring in SVG data I can get it back to mm quickly "

The customer has also send the drawing in DWG. The DWG file opens in CorelDraw in the correct format, but unfortunately Sheetcam cannot open a DWG. I end up opening the DWG in Corel, and exporting as an SVG, which Sheetcam can then open. While cumbersome, it at least gets me a correctly dimensioned drawing.

Have any of you run across this issue? How do you address it? My concern would be getting a file from a customer with no dimensions, and just "assuming" it's an accurately dimensioned file (after all, they supplied it). It would suck to cut and present that product.

Do you have customers supply dimensioned files/images with their technical drawings? And/or have the customer give you the desired/drawn size for stuff, so you know what a given dimension is supposed to be? This one could have bitten me in the butt, luckily we found it at the import stage.

Thanks!

[whiskeymike]

I have not seen this issue, but I would have him export as DXF. I go from illustrator to sheetcam, almost exclusively and never had it off size. I would also use 300 dpi, and inches or metric units.

I don't cut on demand for customers, but it seems like it's hard to get around checking the file. Otherwise you'll have more lost material or arguments with the customer than you want to have.

[Gamelord]

I always have them send the exact size dimensions on the part whenever possible. That way I can double check it before cutting to make srue it is exact. I have never had the issue you are talking about though. You can pre-set corel into metric or inch units before you import your drawings. DPI settings shouldn't make any difference at all with vector images.

also, easy way to check the image for size (if it has definate edges) is to press ctrl +A to select all and then look at the size boxes on top to see what size the image is coming in at. If you ever need to adjust it then you can do so by manually typing in the size the drawing needs to be. Make sure the lock is selected so that it adjusts proportionately.

[whiskeymike]

DPI settings shouldn't make any difference at all with vector images.

Good point. Illustrator supports ppi for raster image elements that are embedded, but it shouldn't be related to this issue.