Trying to project a sketch to a spherical surface then push/pull sketch elements

[Anonymous]

Hi,

I'm very new to Fusion 360 and am having trouble with what I am assuming is a very simple problem but I cannot for the life of me figure out how to solve it.

I have uploaded my .f3d file if that helps at all, but basically I have a sketch which I have projected onto a spherical surface, and I want to be able to use the push/pull function to create holes in the surface.

The sketch is just a bunch of small circles and a large one in the middle. For some reason I am able to use push/pull for the centre circle, but not the smaller ones surrounding it.

Initially all of the circles in my sketch aside from the centre one had a blue line, so I set the dimensions of them until they were all black but this still didn't solve my problem.

Any help appreciated, thanks a lot.

[matt.oosthuizen]

Hi @Anonymous 

Welcome to the forums!

If you are wanting to cut holes into the sphere, based on the initial sketch on the bottom of the body, you could simply use the extrude tool.

You can offset the extrude to ensure the bottom face of the body is not cut into.

I also saw that in your project the circles were projected to the closest point, which caused the smaller circles to be squished into the center. In most cases it is better to project to surface using a vector to guide the projection.

Please find attached my edited version of your f3d file. I hope it is what you were after.

If you have any other questions or I have misunderstood, please let me know!

Otherwise, if you are happy with this solution, please press the accept solution button on this reply.

Kind regards,

Matt Oosthuizen

[Anonymous]

For some reason my reply got deleted, but to keep it brief:

Thanks for the reply, it was very helpful. It wasn't quite what I was looking for, but I realized I didn't include enough information in my original post about what I am actually trying to do.

Basically, I would like the vector I extrude each circle on to point towards the centre of the sphere. I was hoping that by projecting to closest point instead of along the z-axis vector that I could then somehow use the projection vector to extrude the shapes. The other reason I chose extrude to closest point was because, as far as I can tell, it preserves the shape of each circle when viewed from the centre of the sphere, whereas using project along vector makes each circle appear as an oblong when viewed from the sphere's centre.

So my question really should have been what is the best way to go about this? I realize that I could create an individual "plane at an angle" for each circle that isn't the centre one, then simply extrude a sketch to get the desired result. However this seems overly tedious when the program is creating the vector I want in the process of projecting the sketch onto the closest point of the spherical surface, so I am hoping there is a way to utilize this (or alternatively another solution that doesn't require as much manual input on my part).

Thanks,

Lachlan

[etfrench]

Perhaps another way to do this is with the loft command:

The vector line was done in a 3d sketch, but wasn't used in the loft. 

Notes:

1. Use a pattern to create the other holes. 
2. If the holes need to be the same size as the original, then use Plane on path at each end of the vector line and draw the circles in sketches on each plane. 
3. The current hole which tapers towards the centerpoint should have been drawn on a plane on path at the beginning of the vector line in order to be perfectly cylindrical.

[matt.oosthuizen · Accepted solution]

Hi @Anonymous 

Please find attached my edited file.

My work flow was as follows:

1. Project the sketch as you previously had done.
2. Created a single plane using a point of the projected circle, the original circle and a point perpendicular to the original circle point. 
3. This plane allowed me to create a linear path from the original circle sketch to the projected circle sketch.
4. Using this path, I then used the sweep tool ( a loft tool could also be used) to cut the circular shape along this path through the sphere.
5. Then using the circular pattern tool around the Z axis origin I was able to repeat this cutting process for all the other circles.

I hope this is what you are after! If so, please accept the solution.

Kind regards

Matt Oosthuizen