topic Loft with a rail from two splines in Fusion Design, Validate & Document Forum

Loft with a rail from two splines

Anonymous — Wed, 15 Apr 2015 19:14:43 GMT

I'm trying to make a loft with two rails. one of the rails is constructed from two splines as shown

I could only make it work when the rail is a single spline. is there a way to have a rail from a couple of splines/arc/line?

Re: Loft with a rail from two splines

bob_holland — Wed, 15 Apr 2015 22:22:17 GMT

JonFu,

Have you looked at doing a Patch Loft?

http://knowledge.autodesk.com/support/fusion-360/getting-started/caas/screencast/Main/Details/26a71cde-a391-4c8a-b923-a20848059074.html

Please try this and let us know.

Re: Loft with a rail from two splines

Anonymous — Wed, 15 Apr 2015 23:49:56 GMT

Yes, I tried and got this:

I'm trying to build a projecy I did in solidworks with this workflow. here is the sketch and surface:

When I used a single spline for the rail in Fusion insted of two it worked but it's not the form I need.

Is there a way to make a block from the splines?

Re: Loft with a rail from two splines

Simon.Hern — Thu, 16 Apr 2015 09:28:26 GMT

Hi JonFu.

In Fusion, rails are required to be smooth. A rail can be made up of multiple curves, but those curves must connect smoothly, which is what's going wrong in this case. This is the meaning of the error message "The guide (i.e. rail) is not G1 (i.e. smooth) between first and last sections."

Since the profiles aren't required to be smooth, you can often get the desired result by switching around the profiles and the rails. But unfortunately that won't work in this case because one of the profiles is also not smooth.

To make the model you require, I think you'll have to build two (or more) lofts. If you build a middle profile by hand (like the one shown in your solidworks picture) then you can loft from the start profile to the middle profile, and then loft again from the middle profile to the end profile.

Simon

Re: Loft with a rail from two splines

Anonymous — Thu, 16 Apr 2015 20:27:18 GMT

Thanks, I'll try it

Re: Loft with a rail from two splines

ADSKDJW4 — Thu, 16 Apr 2015 20:44:40 GMT

Thanks for jumping in, @Simon.Hern! Let us know if you need further assistance as this is more a limitation, @Anonymous If this is something as is you want to see improved please consider posting this in the IDeas forums? A couple of useful links are below.

Fusion 360 Idea Station
Fusion Product Roadmap Update

Best Regards,

Don Warner