Tracing a shape imported from png file

rex_hanson

A friend of mine created a png file of a 2D shape outline using Inkscape. I'd like to use that shape in a sketch so I can extrude it. Is there a way to do that?

NeilCooke

The profile must be shaded for it to extrude. One trick to find where the problem lies is to draw a line across your profile and move it around to see where the problem is. In this case the highlighted vertices do not touch. Also, for some reason, every entity is duplicated twice over the top of each other.


Also, rather than offset the sketch entities, extrude the profile solid then use the shell command to hollow it out.

Tony_C_

You can import on image and put it on a sketch plane then trace it. 

philip_thomas

There is another thread with an example.
https://forum.onshape.com/discussion/comment/33693

rex_hanson

Thanks for answering my question. Sorry I'm not too enthused with the answer.

I was hoping to have something that would allow me to simply select the edges. Better yet, select the middle and automatically grab the entire profile. Manually adding a bunch of points around the perimeter is tedious and error prone. There is the added problem that some of the edges are straight and some are curved. So putting a spline through them will have to be in a piecewise fashion in order to get the straight sections straight.

philip_thomas

@rex_hanson - I understand and apologize for the fact that Onshape might not do exactly what you're looking for.

I also don't want you to wait around for the 'next' 3 weekly update only to be disappointed each time - our pro users have given us a long list of production-necessary requirements that we will be working on for a while and to be frank, this isn't on the list.

Have you tried looking at some of softwares that come with desktop engravers? These applications tend to be more along the lines of supporting the type of functionality that you are looking for (specifically turning pictures into toolpath with z height grading)

At the hobby-level, Fusion360 can read SVG files and generate an outline.
At the pro-level, Mastercam can do what you're looking for - https://www.youtube.com/watch?v=Po8_RnHlsJo
There are probably others in both categories

I hope this helps you.

brucebartlett

If it's in Inscape as paths why don't you export as a dxf rather than png and import into Onshape that way?

rex_hanson

So my friend exported the shape as a dxf. I was able to upload that and then import it into my sketch. But now when I try to extrude it the extrusion fails. I then tried to use the offset tool and it won't create an offset. It allows me to select the edges, but it won't create an offset. Not sure if I'm doing something wrong or what!

Jake_Rosenfeld

Hi @rex_hanson

Can you post the URL of your document with the DXF in it here? It'll be easier to help if we can see what's going on.

rex_hanson

Here it is:
https://cad.onshape.com/documents/b93bcfee7b328fad0af64039/w/39747b556ec570dd85c6b8a5/e/d43dad017ab9001e8eed5ea8

I'm working in the 'New W' tab.

NeilCooke

The profile must be shaded for it to extrude. One trick to find where the problem lies is to draw a line across your profile and move it around to see where the problem is. In this case the highlighted vertices do not touch. Also, for some reason, every entity is duplicated twice over the top of each other.


Also, rather than offset the sketch entities, extrude the profile solid then use the shell command to hollow it out.

rex_hanson

It turns out there were two or three points that were not coincident. That crossing line trick is nice. Thank you!

tj_thorniley

FYI, Mobile (Android) App Developers:

Was able to open it in Google Chrome long enough to save a copy though. Just thought you should know.

vondes_vodes

how its work in the mobile-phone-tracker on Android?