Tightening binding posts problem

I use an appropriately sized socket (without the wrench) to hand tighten.

In addition, where the speaker cables exit the spade, I will point the cables at about the 4 o'clock position (instead of straight down at the 6 o'clock position). As I hand tighten using the socket, I'll using the other hand to turn the spades/cables toward the 6 o'clock position simultaneously.

This method seems to work quite well at providing a very snug connection between spade and binding post.

-IMO

I had the same problem with binding posts that were plastic sleeve over metal lug with a burr that seats in the plastic. Over time, changing cables and tightening stripped the plastic over the metal and I had to replace them with all metal binding posts. Michael Percy has a good variety.

I'll second Creeper's recommendation.

Stehno's suggestion is the same method that I've used quite successfully for many years. Try to get a grip with a socket around the post (just use your fingers around the socket - don't torque too liberally with a ratchet driver or you may strip the threads).
Also, place the spade lug onto the post at about 45 degrees counterclockwise from the desired final position. As the post rotates tighter, turn the spade in a clockwise direction along with the post. They'll end up at a much tighter final position by doing so.

If they are metal, I would suggest either the AQ wrench which accepts 7/16" and 1/2", or just use a nut driver. If they are plastic, fuhggediboudit!