Table issues please support asap!? i am attempting to make a beer pong table that folds...

i am attempting to make a beer pong table that folds within half. the problem is i have to put the hinge on the top of the table. I have put four container bolts on the bottom but yet it still "V' contained by the middle any ideas??
Answers:    your design is wrong
the hinge go on the bottom of the table
what you do is build 2 boxes out of wood strips
then you attach the 2 table tops to them
afterwards you flip them over on the floor table top down
then you attach the ''piano'' hinge
when it's adjectives together and you turn it over the pressure between the ''walls'' you have made should keep hold of the table flat
this is how comercially made units are put together
cut of the trick is to use a very diaphanous table top so as to keep the freight down. and therby the pressure againt the hinge
KABISH?
that barrel bolt perception is a good one but as you can see yourself,, they are lately too dam short to abet brace anything. But you are on the right track as far as adding auxiliary bracing