Chamfer or angle-cut along a complex shape

[evosiege]

Very much a novice. I'm trying to model a child lock for a sliding door for 3D printing, similar to this one on Amazon. I have the basic shape, but I would like the bottom edge of the wings to be angled so they're easier to grab when it's laying flat on the door. I tried chamfer and fillet, but I got numerous errors that I honestly don't understand. I currently have a very rough solution in place as the final step in the attached file, but ideally, I'd like the slope to follow the edges of the wings for a better aesthetic effect. 

I'll also welcome any additional advice on workflow, file setup, etc., if anything is apparent while looking over the file, though of course that's unnecessary. Thank you!

[davebYYPCU]

The last Extrude in the timeline appears to have worked OK.

The wings need the same fillet top and bottom on both to allow for the (moving?) swing.  Because of body shape - has to be a new fillet command with all 8 new edges after the wing body cuts.

Because you are not using Components, Joints are unavailable. 

(You have enough modelling for the Joints arrangement but without the Components,) 

You will have to Modify > Move > Rotate, with the wing hinge axis position, up off the table, on both or either side.

Might help...

[evosiege]

Thanks for the catch on the hinge! I had that set before, but because of some weirdness in the Extrude->Intersect command, I had to remove those. I added them back in, and set up joints on the wings. Unfortunately, I still get an error trying to angle that bottom edge. 

I forgot to mention in the original post, but one of my objectives with the design is to be able to load multiple shapes (such as dragons, birds, planes, etc) and quickly apply the hinge setup to them. Not sure if that changes the best approach. 

[davebYYPCU]

Your file has cut a taper face to both wings. Last extrude.

Are you saying that you want to add an outline fillet / chamfer to the boundary edges?

A top and or bottom chamfer / fillet must not exceed half that outside thickness.

As for other shaped wings, you need to investigate multiple outline sketches, multiple wing constructions.  I don’t think configurations will differentiate source sketches, but could be wrong.

Might help….

[evosiege]

Sorry, I must not have explained effectively. The last extrude is a temp solution. My goal is for the taper to follow the contours of the wings, instead of being a single angled cut. Kind of like if I did a loft from a smaller version of the same sketch, but I can't get that to work either due to intersecting paths. 

[davebYYPCU]

Experiment with small value Chamfer, using Distance and Angle - if it works, change the angle to even less.  I can’t remember the shapes will test tomorrow.

Might help…..