Hi David,

> The next step I had envisioned, after deleting the hightlighted
> trimed surface was to use the edge of the new "hole" as one
> rail of a Sweep to create an inside wall for the air scoop. I
> discovered that I don't have the option to do this.

But yes actually you can do that - any edge can be used as an input curve to surfacing commands like sweep, extrude, revolve, etc... - so you can draw a little curve coming off of that hole edge and then select it and run sweep and select the edge as the rail path curve.

If the edge is fragmented into some pieces, you will need to do a bit of preparation work - either select the multiple edge pieces and then run the Join command to create a new curve that has those pieces joined together to use as the rail, or you can also use the Merge command to merge together 2 edge fragments that touch each other and are smooth where they meet:
http://moi3d.com/2.0/docs/moi_command_reference10.htm#merge

I've attached an example file where I've drawn a little curve hanging off the end of the hole - select it and then run sweep and select the edge as the rail curve.

You may want to place curves at both the start and the end of the rail in situations like this so that you have direct control over how the sweep is shaped at the ends of the sweep.

Was there some reason why you thought that you could not use Sweep along the edge of the hole?

- Michael

Michael,

Thanks to your email- the problem is solved.

The problem I was having is that after the trim/delete is done the newly created curve did not highlight when moused over
as other curves or lines do. I didn't initially understand that the network needs to be highlighted first before the curve(s) will highlight.
This may have been because, as you pointed out, the new curve was fragmented. Once I did a Join on the two segments, the new curve
would highlight as any other curve does.

Looking forward to completing the project.

Thanks again.

Hi David... There is a difference between curves and "surface edges"... To select a surface edge you need to do a "drill down" pick, which is as you describe, selecting the surface then the second pick will target that surfaces edge.. The same is for the faces of solids or joined surfaces.. Select the object then the face will become selectable.. The edges take precedence, so you may have to zoom a bit on smaller faces to be able to target them...

Hi David, yup Burr has described that well - selecting edges is a bit different than selecting a "standalone" curve. To select an edge you first do one click on it to select the "whole object" and then a second click will drill in to select either edge or face sub-objects.

That gives you a method to control selecting either an entire solid (with just the first click) or also going in and selecting sub-object pieces with the secondary clicks.

Check out here for some description of how selection works:
http://moi3d.com/2.0/docs/moi_introduction.htm#selection

- Michael