I have an iron headboard that is 80 inches tall in the center. It's very top heavy - and just plain heavy too. If it's just mounted to the bed frame would that be enough to keep it from falling forward? (as in crushing me when I'm sleeping) I love this headboard but afraid of it too. Any suggestions?
That frame is built of heavy-gauge steel and will likely hold up your headboard without damage. The fact that your headboard is vertical means that there's relatively little stress on the assembly.
However, there may be play in the rivets and other connections which leave the headboard a bit wobbly when the bed is used. To completely remedy that you'd probably need to add a diagonal brace near the floor, between the horizontal frame rail and the headboard leg, creating a larger gusset. You could do so with a simple double-bent 1/8" steel or 1/4" aluminum bar stock attached with carriage bolts. Something like so:
| | ___________/| | ___________ | | -- \| | \ | | \ | | \ | | \ | | || | | |
I would 1) turn the headboard around so the already attached brackets are flush to the wall (attach at that point) then, 2) use "square tube brackets" to attach the headboard to the wall (at the highest point where the mattresses would cover the brackets.
The square tube bracket, to which I'm referring, would be like this (but of the proper size) http://www.gutterspares.co.uk/4t834---25-square-pipe-bracket-1250: