Single line DXF

[Old Geeser]

I am trying to laser cut a cardboard box shape from a dxf file. When I make the .DXF file, I get 2 lines around the periphery in most places instead of 1 They appear to be about .001" apart. Am I doing something wrong when I created the "thin Extrude" or is there a problem with the function? Thanks.
Karl

 

[HaroldL]

I think it would be better if you exported the sketch as a SVG then convert that to the DXF. That would be the shorter workflow. Otherwise create the part as a Sheet Metal part, if you have that function, and create the dxf from the flat pattern.

 

[Old Geeser]

Thanks Harold, but I do not see SGV as one of the Export options and I do not have the sheet metal option either. I am using Design version of Alibre.
Karl

 

[HaroldL]

I do not see SGV as one of the Export options

Right click on the sketch in the Design Explorer, it is an option in the pop up menu.



Give me

 

[Old Geeser]

Thanks again Harold and I feel I am getting closer. I now get a svg file. However, I am still not quite there. What program do you recommend to convert it to dxf. I tried loading it in freeCad and it didn't display anything and gave me lots of error messages. I looked at the binary file and it looks like it is organized into blocks, each block is fifty bytes long. A sketch of 3 lines, generates 14 blocks. That's as far as I can go without help. The format of those blocks would be a big help. Any direction you can direct me to would be appreciated.
Karl

 

[HaroldL]

I think this has come up before and someone suggested an online converter. I used Inkscape to open the SVG and save it out as a R14 DXF. I was able to open it in Alibre and it came in as several blocks. After exploding the blocks I was able to apply a dimension to check the size against your original file and it was the same.

Here is the dxf:

 

[DavidJ]

Thin extrude will create thickness, not a line.

Could you just sketch this directly in the drawing workspace? (use 'sketch on sheet') - you can even copy from the part sketch and paste into drawing sheet (but be careful of scale).

 

[Old Geeser]

Thanks David. But for some reason I am just not comfortable sketching in the drawing workspace.
But Harold gave me the info I needed to use the .svg output. I spend all day yesterday writing a reader for the .svg output. Lucky for me the file format is ascii text and easily read. For an 80 year old to spend a 12 hour day coding is lots of fun anymore. I got it reading lines & circles now and am on to partial arcs. It outputs the start & end points and the radius. Where as .dxf requires center point, beginning angle and ending angle, & I need to figure a way to select between the 2 possible solutions. So, I've got my work cut out for me for today (and maybe more). Another interesting point is that the data is output at 96X the scale. I wonder if files always use this same scale factor?
Thanks again, Harold.

 

[DavidJ]

I seem to recall the SVG uses 96 DPI, there's a thread mentioning this somewhere on the forum.

 

[srjacob]

I have a dxf file, but when I open it in Alibre, it gets open into the drawing workspace. How do I get it to open in the part workspace (I want to create a part out of it).

Thanks, Steve

 

[NateLiquidGravity]

Imported drawing to part:
Open the file.
You edit the sketch in the drawing.
Copy the sketch entities.
Open the part.
Start a sketch.
Paste the sketch entities.

The reverse also works. You can copy and paste from part sketch to drawing sketch.

 

[Old Geeser]

First, thanks for the help you gave me earlier in getting single line data using the "export SVG" function. I have managed to parse out the line and circle information. However, I have spent the last week trying to understand the arc data. It contains 2 points (start & end) and the radius. I know that there are two possible circles that will pass through the points, and a given radius. I seem to need one more piece of information in order to come to one solution. I tried all arcs in a counterclockwise direction from first point to second point. It did not work. Can anyone point me in the direction I need to look?
Thanks
Karl

 

[Old Geeser]

Thanks to all who helped me with this, especially Harold who put me onto the SVG file. I finally, after much research, have found the missing info that I was searching for. It seems that all partial arcs are ccw unless the sweep flag is set. Bingo, it seems to work just fine.
Karl