Projecting curves onto surfaces & solids

[So not a Guru]

I struggle with this often. I need to create surface geometry, to get smooth toolpath motion. So I draw my lines in 2d, then project them onto the combination of surfaces (using smooth composite) & solids that I want to use for creating my geometry.

Often, my resulting geometry has small (0.0002" - 0.0006") gaps between the elements. Is there a better way to ensure I get connected geometry?

[Giang-TT]

There is an option called "Join result" which allows you to join the curves as long as the gap distance less than input value

[htm01]

22 minutes ago, So not a Guru said:

Often, my resulting geometry has small (0.0002" - 0.0006") gaps between the elements. Is there a better way to ensure I get connected geometry?

sometimes I just have to draw a line connecting them

[Aaron Eberhard]

24 minutes ago, GiangTheTool said:

There is an option called "Join result" which allows you to join the curves as long as the gap distance less than input value

This is the best option you have, unfortunately..  The good new is that if you create a Curve Spline from all the pieces, you now have the ability to "smooth sharp corners" which is the same thing as Refit Spline.  Both of those will clean up the results nicely.

The problem that you have is if it's outside of the gap distance in Join Results, or the results are incongruent,  how do you want the software to fix it?  Every case that's outside of the gap distance is a big "unknown" and guessing at this probably won't be right the majority of the time. 

The best thing to use manually is the Blended Spline command to smooth out the gaps.   Then use Curve Spline with Smoothing to make them all one piece if you want that.

[huskermcdoogle]

3 hours ago, Aaron Eberhard - CNC Software said:

The best thing to use manually is the Blended Spline command to smooth out the gaps.   Then use Curve Spline with Smoothing to make them all one piece if you want that.

If the gaps are very small, trim them back a little bit before put a blend spline between them.

[So not a Guru]

Thanks guys, I rediscovered the join results about 2 minutes after my 1st post. I've used it before, I just brain-farted again.

4 hours ago, Aaron Eberhard - CNC Software said:

The best thing to use manually is the Blended Spline command to smooth out the gaps.   Then use Curve Spline with Smoothing to make them all one piece if you want that.

 

43 minutes ago, huskermcdoogle said:

If the gaps are very small, trim them back a little bit before put a blend spline between them.

Thanks, I hadn't thought to use these tools in congress with the projection before.

[So not a Guru]

4 hours ago, Aaron Eberhard - CNC Software said:

Then use Curve Spline with Smoothing

Where is this function located?

[huskermcdoogle]

In the spline tools dropdown.  It's named Spline From Curves.

[So not a Guru]

1 hour ago, huskermcdoogle said:

In the spline tools dropdown.  It's named Spline From Curves.

Thanks Nick.

[Aaron Eberhard]

19 hours ago, huskermcdoogle said:

If the gaps are very small, trim them back a little bit before put a blend spline between them.

The nice thing about using Blend Spline is that you don't have to trim it ahead of time.. Since the process is to choose which spline to start and then where to blend from then you get to choose which spline it's going to and where to blend to on it, you can save that step.

 

 

[crazy^millman]

4 hours ago, Aaron Eberhard - CNC Software said:

The nice thing about using Blend Spline is that you don't have to trim it ahead of time.. Since the process is to choose which spline to start and then where to blend from then you get to choose which spline it's going to and where to blend to on it, you can save that step.

 

 

Another trick is to use the create point segments and you can put points on each spline a certain distance and then use those points as your snap to point for the blend spline process to really dial down exact places you want them blended from.

[Colin Gilchrist]

You can also use the "Surface > Finish > Project" and "Surface > High Speed > Project" paths to have the tool "remain tangent" to the surfaces, without having to worry about getting "3D" geometry. I use 2D geometry all the time to drive the 3D paths, especially with things like finishing ramped walls. One really cool feature of doing this is using the Gap Distance to make the tool retract for "finish" passes, but "zig-zag" for the rouging passes. I'll do that in aluminum to save time, especially when finishing with a ball mill in tight areas.