I've got the same question; and to add to it, once you've done that, you still have to consider the upper/lower combinations. It would be nice if
AV could be copied to all combinations of those glyphs: AV, av, aV, and Av.

Save the metrics out as a text file, manually* duplicate/modify the kerning part, then re-import.

* Or recruit a word processor's find/replace function.

hhp

Too simple. Thank you :)

Use the 'Paste Special' function from the Edit menu.

I feel like an old dog who needs to learn new tricks.

hhp

Why not create an OpenType feature to substitute the uppercase characters when their lowercase counterparts are typed?

David

Or assign the same glyph to different Unicode values.

@HVB: I didn't even think about aV, av, and Av... that introduces a whole new problem...

@John Hudson: Thanks, this worked! Using paste special and selecting left and right kerning option works beautifully.

@Quadrat: I've never messed with OT features, and regardless I think this font is ultimately going to be a TTF. For some reason when I generate the font it looks very wrong when I export as an OpenType font, but fine when I choose TrueType. The characters are very complex so I'm sure I could just be doing something incorrect when generating the font, but for now it looks like I'll have to stick with TTF.

@Theunis: Didn't even know you could do that! Seems a little complicated for me, but I'll look into it.

Or assign the same glyph to different Unicode values

That's what I did with the Ambicase fonts.

For all-caps fonts, I find double-encoding the glyphs to be more convenient during development, even if I end up expanding them at the end. Since the "lowercase" is literally the same as the uppercase, it doesn't matter which one you edit/kern/etc., and there's no need to worry about case when navigating or typing out test strings. Then if I'm feeling especially standards-compliant, before generating I can run a macro that creates properly-encoded lowercase copies and adds them to appropriate kerning classes.

A TTF can still have OT features.

Especially since nowadays TTF is took to mean TT-flavoured OTF.

I'm in the same situation... I've tried the solutions that are on here, but I couldn't get a single one to work.
Would someone be kind enough to write a short step-by-step tutorial of the solution they're using? Thank you very much :)

1) Ensure all lowercase letters are deleted
2) Select uppercase A
3) In the Glyph Properties panel change the Unicode value "0041" into "0041 0061" and press the Apply button
4) Repeat step 2 and 3 for the other uppercase letters (0042 -> 0042 0062, etc)