05 Jan. 1988
How to build a swing set frame,christmas woodworking plans free,micro houses cost,wooden rose trellis plans - Review
I am not sure what exactly kind of metal brackets you mean -- but you would need ones *expressly designed* for constructing an A-frame swingset. The thing is, in order to make a strong stable swingset you need some rather exact and complex multiple angles where the legs meet each other and the top beam.
If you were wanting to build the whole thing out of wood, there are various different designs (plans available in better-stocked hardware stores, in books in your local library, in books through interlibrary loan, and presumably on the internet tho I cannot recommend any in particular). 
Whether to make the top beam a 4x4, 4x6, or doubled (or tripled) 2x lumber depends on what forces you're expecting the swingset to withstand, how long the unsupported part of the beam, and what kind of hardware you are intending to use for hanging the swings from.
There is not very much keeping it from flexing from end to end (imagine a kid swinging *sideways* on a swing, as kids are wont to do, and the forces that exerts on the frame) - basically just one bolt in tension on each end, which is not a very strong arrangement. 

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