Split Face: The projection of tool curve and faces fails.

[RogerInHawaii]

I've got a conical object. I created, first, a tangent plane on the cone, then an offset plane a little bit away from the tangent plane. I did that offset plane because when I first tried making a sketch on the tangent plane and doing a Split Face from it to the cone it failed, so I figured maybe it was because the sketch was right up against the cone.

I created a new sketch on that offset plane and tried to use it (actually just one small part of it, one of the small circles) as the splitting tool, but I get the same error, namely:

The projection of tool curve and faces fails.

UNDEFINED ERROR!

I get the same error no matter what outline on the sketch I use as the Split Tool, or when I select ALL the outlines on the sketch. It just will not do the Split Face operation.

I've attached a screen shot

I need suggestions.

And in case you're curious, I'm creating the panels that constitute the outer shell of the NASA Mercury S[pace Capsule. This particular part is the Antenna plate on one of the panels.

[davebYYPCU]

Are you actually trying to split 6 faces, under that little circle, 

I would attempt one at a time, 

maybe Select Through, turned off, might help.

[RogerInHawaii]

I don't know where "Select Through" resides as an option. It's not on the Split Face dialog. If you can tell me how to turn that off, I'll give it a try.

As for the number of faces on the target object: You'll notice a bunch of grooves to the right, one above, several below, the area where I'm trying to do the new split face. That area, which kind of looks blank, originally also had grooves in it. I made a sketch and did a Revolve operation across those grooves to "fill them in", using a Join operation. That SHOULD have left that section nice and smooth. It does LOOK smooth, but it left a kind of "ghosting" of the original grooves and they show up when I try to do something like this Split Face operation. 

Is there a way to get rid of those "ghost" lines so that there's really only one target face to deal with?

Plus, I did try using only one small feature of the sketch as the Split tool, going on to a section of the target that was only one face, and even that didn't work. See attached image.

[mavigogun]

A few things first.   The Selection Controls are found at the far right of the bar at the top of your Fusion window- not as part of the Split dialog box.   Use the Photos button at the top of the text window when posting- opening and expanding each image is a tedium being placed between you and help.

Before going any further with this design, you need to confront the massive number of warnings in your Timeline- in only the limited portion shown in your screencapture, there are 15 Features with Warning flags!!!    I shudder to think how many populate the entire design.    Troubleshooting ways to perform this Split now would be folly.

[davebYYPCU]

Select through is in the selection filters.

If those hidden / replaced grooves are still there, select through will find them. 

Dialogue box shows 6 faces to Split, red flag right there.

Yellow icons are not good for you, Red are worse.  Do not use the delete key, modify instead.

Attaching the file will let us find what's wrong, as it is we cant find it, in a picture.