John, thanks for the pics,Yes, multi hour tests at 720 watts didn't reveal any problems. The contact area is more than adequate, if you are getting heat buildup, once again, I suggest you check your connections. Resistance is what is causing the heat.
Yes, extended testing at 720 watts, I was testing the modification of the 800 watt supply for the RD6012 at full power output (12 amps at 60 volts).
I have a lot of experience in this area, you might want to check your contacts. Once again, crimp spade lugs onto 10 gauge wire, unscrew the outer cover of the banana jacks, insert spade lug, then tighten.
The picture you posted above is not even close to a good connection.
This is what your connection should look like.
can you show us how you crimp those on to the 10 awg wires?
I will measure the resistance between the spade and other end of my wire, I am curious to figure out the source of the heat.