There probably is a lot of variation in the weight of the pipe flanges - they were so hard to get in San Jose that we have 4
different kinds on our goal - since they probably can be a couple of ounces different in weight - this times 32 can be a 10 to 20lb
difference - same thing goes for the iron angle - if you ommitted it
or used aluminum instead - that probly id another 10 to 20lbs diff.

SO if your really worried add some weight to the bottom!