hss 12 sizes

huangyhg

hss 1/2 sizes
does anyone specify hss 3.5, 4.5 or 5.5?
has anyone actually seen these sizes fabbed and erected?
i notice "half" sizes are listed in the aisc 9th ed. and  are an option to select in the enercalc engineering software.  
one steel distributor/warehouse says half-sizes are not even made while another said they do stock it, though it is less popular than the "whole" sizes.
your comments please ...  
thank you!
i have spec'd 2 1/2" sq. and 3 1/2" sq.  the 2 1/2" was used as a deck edge support on top of a beam.  the 3 1/2" was used as a column.  clearances and architectural constraints would not allow a 4" sq. tube.
we have used the 2 1/2" tube exactly like what sperlingpe did.
half sizes, albeit square or round, are readily available by a multitude of suppliers.  check
i once used 1 1/2" tube for connection design.  and 3 1/2" tube as a column like sperlingpe did.
i have used 2.5" commonly for outriggers using steel joist framing, or in places where i simply don't wish to use vs joists (like fire rating issues).  i've also used 5.5", though not too often, for storefronts in grocery stores and retail centers.  i'm located in orlando and haven't heard of a problem with 1/2 sizes, yet anyway.  
in our office we have used hss 4.5" & hss 5.5" quite often and no one has ever complained about not finding those sizes.
as pylko said, check with aisc. they regularly publish a "shapes" list that gives the producer and shapes available at the time of print.  this comes out in the modern steel construction magazine.  there is also a "black book" dealing with connections for hss members that has every size produced listed.