Is there a way to create a smooth fillet or chamfer on these two curves so they blend correctly with the rest of the model? Simply using the FilletEdge tool does not work

I’d suggest removing the surfaces to the right and using Sweep2 with tangent continuity to the rails which will be chained surface edges. You might also try NetworkSrf with two separate sections meeting at a BlendCrv in the middle.

It also looks like you have Flat shading on in the viewport settings in case you don’t want it to look faceted like this when shaded.

Thanks for your reply Brian. I think I understand what you’re trying to say. I want to reiterate, or rather further explain what I want result I want. Maybe I didn’t portray it correctly. I want to fillet or chamfer each one of those curves separately/individually. When I use the FilletEdge tool, the fillet doesnt extend to the end of the curve in either situation and causes a hole in the model. I think the problem is the fact that these two curves meet on either end at a very pointed vertex. How can i work around this?

Also, thanks for the Flat Shading tip!

If you make a planar surface from the curves that make up the gap, you can then call FilletEdge and by adding handles (see the commands in the command line), you can set the fillet size to be 0 where the two curves meet at each end of the gap. Does that help?

Do you have these surfaces still prior to the filletedge? I’d like to see the before and after if possible. Please post this in one file here if you can and I’ll take a look. It might be possible to use portions of the fillets for the final result.