oi, lets get this a bit more fleshed out.
short hop nair fast fall jab works on the opponent when? at any percentage.
not while they are shielding? If they are shielding, you can't start the combo, of course. Before you do anything, you need to hit confirm with the start of said combo, which is the Jab.
How to: A,A(Quickly) > did they shield it? No? > short hop > nair > fast fall. You should be doing the act of punching > jumping > landing, in the space of a second - just do it as fast as you can.
are you saying it works if the nair hits them? it couldnt frame trap their shield surely? to an extent it
does frame trap them in their shield, but only if they aren't skilled enough to get out of it once they shield an attack.
how late are you throwing out the nair? nair must come out straight away, same with d-air. I use Y and A for short hopping nairs - I essentially just drag my thumb down over both Y and A quickly, and then fast fall it.
"Jab x 2 > short hop > d-air > fast fall > jab > turn around and uptilt is another way of wracking % while keeping your opponent frame trapped"
does this work on shield too? on hit? like wheres the frame trap? Pretty much everything in Fox's attacking kit synergies with itself. This one is generally harder to do in my opinion; the key to doing it successfully is learning the timing of Jab Locking - it is done by a very precise double tap (sets) of the A button. Failing to jab the enemy fast enough yields no frame trap, minus 50 points. Wait too long to start the next set of Jab Lock and you'll go into a full jab animation.
After learning to do that, you can move onto alternating between other attacks between your Jab Lock sets.
Example: Jab x 2 > Jab x 2 > turn around Up-Tilt > turn around Jab x 2 > ?anything?
Remember to stay with your opponent as you're Jab Locking them as much as you can; move with them. D-Air needs to be stick buffered as well (unsure if name is correct? can't remember) = mash c-stick down right after you jump.