Can't offset more than 0.039"

[difalkner]

I have a simple curved shape, a guitar body, and want to offset the outline 0.10" to the inside but when I hit 'O' and get the default 0.039" I'm unable to change it, I get an error message. The error message I get is 'The sketch offset created no geometry.  Modify the offset dimension or verify the changes are correct.'

I drew this in CorelDraw, exported as dxf, and brought it into F360.  The drawing appears clean but maybe I'm missing something.  

What can I do to get this simple curve to offset 0.10" to the inside?

[davebYYPCU]

Can’t access the file at the moment.  Fusion does not play well with imported geometry.

Does the default value work?

Offset the curve in Corel Draw, before importing.

Might help....

[difalkner]

Yes, the default value works just fine.  I've done this dozens of times with dxf files imported from CorelDraw and no issues that I recall.

[etfrench]

It's about a three minute job to draw in Fusion 360 with a control point spline.

[difalkner]

I assume then the offset would work as expected, correct? But why have I been able to do this in the past and this time it fails?

[etfrench]

The geometry is really bad.  Take one segment and offset it:

The end is overlapping.

Adding tangent constraints shows how badly the line segments are formed:

[difalkner]

Ah, so I just didn't zoom in close enough to see those.  Thanks, I'll work on it!

[difalkner]

It took me a few hours working from a couple of photographs.  I'd love to see how you can do this in three minutes, there's probably a lot for me to learn if you can do it that fast.  Of course, I already have the exact shape I want now and that's what took so long, but still I'd love to see how you do this to get it precise in three minutes.

[difalkner]

The interesting thing is that I exported the exact same drawing from CorelDraw as svg and brought it into F360.  Offset works perfectly so I guess there's an issue with the dxf file export out of CorelDraw.  

I like using dxf because the file imports at precisely the same dimensions whereas svg has to be scaled.

[etfrench]

😀 It would probably take a little longer😂  It does get easier the more you do.

[difalkner]

I've actually done it for years in CorelDraw, a little bit in F360, and am fairly proficient at it but this wasn't just copying an existing guitar.  My goal was/is to create my own design so there was a fair amount of drawing, stepping back to look, walking out of the room to come back and see if I still liked what I had drawn, then repeating those steps many times.

I'll give it a shot drawing this in F360 now that I have my design down and see how that works out.

Thanks, guys!

[etfrench]

There are quite a few guitar heads on the forum so it should be easy to get help.  There may even be a facebook group for Fusion 360 guitars.

[difalkner]

I didn't even think about that - thanks!  Most that I've seen seem to do electric solid body guitars that, while not really 'simple', are very simple relative to acoustic guitars.